CNIM ABRET Practice Questions

1. Transforaminal lumbar interbody fusion (TLIF) surgical procedure is related to the lumbar region.

True

False

The explanation for the given correct answer is that transforaminal lumbar interbody fusion (TLIF) is indeed a surgical procedure that is specifically related to the lumbar region. TLIF is a type of spinal fusion surgery that is performed to treat conditions such as degenerative disc disease, spondylolisthesis, and spinal instability in the lower back. During TLIF, the surgeon accesses the lumbar spine through a small incision in the back, removes the damaged disc, and fuses the adjacent vertebrae together using bone grafts and implants. Therefore, it is true that TLIF is related to the lumbar region.

Explanation

The explanation for the given correct answer is that transforaminal lumbar interbody fusion (TLIF) is indeed a surgical procedure that is specifically related to the lumbar region. TLIF is a type of spinal fusion surgery that is performed to treat conditions such as degenerative disc disease, spondylolisthesis, and spinal instability in the lower back. During TLIF, the surgeon accesses the lumbar spine through a small incision in the back, removes the damaged disc, and fuses the adjacent vertebrae together using bone grafts and implants. Therefore, it is true that TLIF is related to the lumbar region.

2. In order to prevent any tongue injuries due to TcMEP stimulation we should always use:

Bite block

ET Tube

Low stimulus

Low pulse width

To prevent tongue injuries during TcMEP stimulation, it is important to use a bite block. A bite block helps to protect the tongue by providing a barrier between the teeth and the tongue, reducing the risk of accidental biting or injury. This is especially important during TcMEP stimulation, as the procedure involves electrical stimulation of the muscles, which can cause involuntary movements and increase the risk of tongue injury. Using a bite block ensures the safety and comfort of the patient during the procedure.

Explanation

To prevent tongue injuries during TcMEP stimulation, it is important to use a bite block. A bite block helps to protect the tongue by providing a barrier between the teeth and the tongue, reducing the risk of accidental biting or injury. This is especially important during TcMEP stimulation, as the procedure involves electrical stimulation of the muscles, which can cause involuntary movements and increase the risk of tongue injury. Using a bite block ensures the safety and comfort of the patient during the procedure.

3. Patient privacy act is known as:

HIPPA

ACNS

ABRET

NPS

The correct answer is HIPPA. HIPPA stands for the Health Insurance Portability and Accountability Act. It is a federal law in the United States that protects the privacy and security of patients' health information. HIPPA sets standards for the electronic exchange, privacy, and security of health information, ensuring that patients' personal health information is kept confidential and secure.

Explanation

The correct answer is HIPPA. HIPPA stands for the Health Insurance Portability and Accountability Act. It is a federal law in the United States that protects the privacy and security of patients' health information. HIPPA sets standards for the electronic exchange, privacy, and security of health information, ensuring that patients' personal health information is kept confidential and secure.

4. Electrode placement on the scalp for SSEP is based on:Which one do you like?

10-20 system

Touch and feel

20-10 system

10-15 system

The correct answer is the 10-20 system. The 10-20 system is a standardized method for placing electrodes on the scalp for measuring somatosensory evoked potentials (SSEP). It is based on the measurement of the distance between specific landmarks on the head, such as the nasion (the midpoint between the forehead and the bridge of the nose) and the inion (the bump at the back of the head). This system ensures consistent and accurate electrode placement across different individuals, allowing for reliable measurement and comparison of SSEPs.

Explanation

The correct answer is the 10-20 system. The 10-20 system is a standardized method for placing electrodes on the scalp for measuring somatosensory evoked potentials (SSEP). It is based on the measurement of the distance between specific landmarks on the head, such as the nasion (the midpoint between the forehead and the bridge of the nose) and the inion (the bump at the back of the head). This system ensures consistent and accurate electrode placement across different individuals, allowing for reliable measurement and comparison of SSEPs.

5. If you drop a subdermal needle on the OR floor, what should you do?

Discard the needle in the sharp bin

Use the needle

Disinfect the needle using peroxide

Leave the needle and use a spare

When a subdermal needle is dropped on the operating room (OR) floor, it is important to discard the needle in the sharp bin. This is the correct answer because dropping a needle on the floor increases the risk of contamination and infection. By discarding the needle in the sharp bin, it ensures proper disposal and reduces the chances of any harm or infection to the patient or healthcare professionals. Using the needle or disinfecting it with peroxide may not effectively eliminate the risk of contamination. Leaving the needle and using a spare is also not a safe option as it can lead to the same risks.

Explanation

When a subdermal needle is dropped on the operating room (OR) floor, it is important to discard the needle in the sharp bin. This is the correct answer because dropping a needle on the floor increases the risk of contamination and infection. By discarding the needle in the sharp bin, it ensures proper disposal and reduces the chances of any harm or infection to the patient or healthcare professionals. Using the needle or disinfecting it with peroxide may not effectively eliminate the risk of contamination. Leaving the needle and using a spare is also not a safe option as it can lead to the same risks.

6. After the surgical procedure, where should the needle electrodes be discarded?

In the red sharps container

In the red garbage bins

In the black sharps container

In clear garbage bags

The needle electrodes should be discarded in the red sharps container because sharps containers are specifically designed to safely dispose of sharp objects such as needles. The red color of the container indicates that it is meant for biohazardous waste, including used needles. Disposing of the needle electrodes in this container helps prevent the risk of accidental needlestick injuries and ensures proper disposal of potentially infectious materials.

Explanation

The needle electrodes should be discarded in the red sharps container because sharps containers are specifically designed to safely dispose of sharp objects such as needles. The red color of the container indicates that it is meant for biohazardous waste, including used needles. Disposing of the needle electrodes in this container helps prevent the risk of accidental needlestick injuries and ensures proper disposal of potentially infectious materials.

7. The back of the surgeons gown is considered as non-sterile.

True

False

The back of the surgeon's gown is considered non-sterile because it is more likely to come into contact with unsterile surfaces or objects during surgery. The front of the gown is considered sterile as it is the area that will be in direct contact with the surgical field. Keeping the back non-sterile helps to minimize the risk of contamination and maintain a sterile environment during the procedure.

Explanation

The back of the surgeon's gown is considered non-sterile because it is more likely to come into contact with unsterile surfaces or objects during surgery. The front of the gown is considered sterile as it is the area that will be in direct contact with the surgical field. Keeping the back non-sterile helps to minimize the risk of contamination and maintain a sterile environment during the procedure.

8. Train of four (TOF) from the foot should be monitored from which muscle?

Abductor hallicus brevis

Flexor hallicus longus

Flexor digiti minimi

Flexor pollicis brevis

The correct answer is Abductor hallicus brevis. The Train of Four (TOF) is a method used to assess the level of neuromuscular blockade during anesthesia. It involves stimulating a peripheral nerve and measuring the resulting muscle response. The abductor hallicus brevis muscle is located in the foot and is innervated by the posterior tibial nerve, making it an appropriate muscle to monitor for TOF assessment. The other muscles listed are not directly related to the foot or innervated by the posterior tibial nerve, so they would not be suitable for monitoring TOF from the foot.

Explanation

The correct answer is Abductor hallicus brevis. The Train of Four (TOF) is a method used to assess the level of neuromuscular blockade during anesthesia. It involves stimulating a peripheral nerve and measuring the resulting muscle response. The abductor hallicus brevis muscle is located in the foot and is innervated by the posterior tibial nerve, making it an appropriate muscle to monitor for TOF assessment. The other muscles listed are not directly related to the foot or innervated by the posterior tibial nerve, so they would not be suitable for monitoring TOF from the foot.

9. You are on the way to the OR for surgery along with the surgeon. The surgeon begins to ask questions about a specific patient by name from the previous week. Since the other people in the elevator are all hospital staff, you can discuss the patient history to save valuable time in the OR.

False

True

Discussing patient history in a public elevator violates patient confidentiality and is a breach of the Health Insurance Portability and Accountability Act (HIPAA). It is important to maintain patient privacy and only discuss patient information in appropriate and secure settings, such as in a private consultation room or during a formal case discussion with the medical team.

Explanation

Discussing patient history in a public elevator violates patient confidentiality and is a breach of the Health Insurance Portability and Accountability Act (HIPAA). It is important to maintain patient privacy and only discuss patient information in appropriate and secure settings, such as in a private consultation room or during a formal case discussion with the medical team.

10. Latency and/or amplitude changes in SSEP responses can result from:

Anesthesia/hypothermia

Technical failure

Surgical manipulation

All of the above

Latency and/or amplitude changes in SSEP responses can result from anesthesia/hypothermia, technical failure, and surgical manipulation. Anesthesia and hypothermia can affect the conduction of nerve signals and cause delays or alterations in the SSEP responses. Technical failure, such as electrode malfunction or improper signal amplification, can also lead to changes in SSEP measurements. Additionally, surgical manipulation can cause physical disruption or compression of the nerves, leading to changes in SSEP responses. Therefore, all of the mentioned factors can contribute to latency and/or amplitude changes in SSEP responses.

Explanation

Latency and/or amplitude changes in SSEP responses can result from anesthesia/hypothermia, technical failure, and surgical manipulation. Anesthesia and hypothermia can affect the conduction of nerve signals and cause delays or alterations in the SSEP responses. Technical failure, such as electrode malfunction or improper signal amplification, can also lead to changes in SSEP measurements. Additionally, surgical manipulation can cause physical disruption or compression of the nerves, leading to changes in SSEP responses. Therefore, all of the mentioned factors can contribute to latency and/or amplitude changes in SSEP responses.

11. When performing EEG in patients suspected of or diagnosed with an infectious disease, the technologist should always:

Perform universal precautions

Use surface pads

Inform the surgeon

Use multiple layers of gloves

Performing universal precautions is necessary when performing EEG in patients suspected of or diagnosed with an infectious disease. Universal precautions refer to the standard infection control measures that should be followed in order to prevent the transmission of infectious diseases. This includes wearing personal protective equipment such as gloves, masks, and gowns, as well as practicing proper hand hygiene and disinfection of equipment. By following universal precautions, the technologist can minimize the risk of spreading the infection to themselves or others.

Explanation

Performing universal precautions is necessary when performing EEG in patients suspected of or diagnosed with an infectious disease. Universal precautions refer to the standard infection control measures that should be followed in order to prevent the transmission of infectious diseases. This includes wearing personal protective equipment such as gloves, masks, and gowns, as well as practicing proper hand hygiene and disinfection of equipment. By following universal precautions, the technologist can minimize the risk of spreading the infection to themselves or others.

12. What is common mode rejection (CMR)?

Cancellation of signals which are common to both of the amplifier inputs

Voltage out divided by voltage in

The misrepresentation of an analog waveform due to sampling too slowly

Phase shifts during use of analog filters

Common mode rejection (CMR) refers to the ability of an amplifier to cancel out or reject signals that are common to both of its inputs. This means that any signal that is present on both inputs of the amplifier, such as noise or interference, will be effectively eliminated or greatly reduced in the output signal. CMR is an important characteristic for amplifiers, especially in applications where there is a need to accurately amplify a desired signal while minimizing the impact of unwanted common mode signals.

Explanation

Common mode rejection (CMR) refers to the ability of an amplifier to cancel out or reject signals that are common to both of its inputs. This means that any signal that is present on both inputs of the amplifier, such as noise or interference, will be effectively eliminated or greatly reduced in the output signal. CMR is an important characteristic for amplifiers, especially in applications where there is a need to accurately amplify a desired signal while minimizing the impact of unwanted common mode signals.

13. The condition due to incomplete closure of the spinal cord is called?

Spina bifida

Spondylolisthesis

Spondylitis

Sublaxation

Spina bifida is a condition that occurs when the spinal cord does not fully close during fetal development. This can result in various degrees of disability, including paralysis, bladder and bowel problems, and learning difficulties. It is a congenital condition that can be caused by genetic and environmental factors. Spondylolisthesis refers to the forward displacement of a vertebra, while spondylitis is inflammation of the vertebrae. Sublaxation refers to a partial dislocation of a joint.

Explanation

Spina bifida is a condition that occurs when the spinal cord does not fully close during fetal development. This can result in various degrees of disability, including paralysis, bladder and bowel problems, and learning difficulties. It is a congenital condition that can be caused by genetic and environmental factors. Spondylolisthesis refers to the forward displacement of a vertebra, while spondylitis is inflammation of the vertebrae. Sublaxation refers to a partial dislocation of a joint.

14. The progressive central nervous system disease that affects myelin and causes weakness, vision loss, fatigue, and imparred coordination is known as:

Multiple Sclerosis

Tinnitus

Ankylosis

Apraxia

Multiple Sclerosis is a progressive central nervous system disease that affects the myelin, the protective covering of nerve fibers. This leads to various symptoms including weakness, vision loss, fatigue, and impaired coordination. Tinnitus is a condition characterized by ringing in the ears, Ankylosis refers to the stiffening or fusion of joints, and Apraxia is a motor disorder that affects the ability to perform purposeful movements. Therefore, the correct answer is Multiple Sclerosis.

Explanation

Multiple Sclerosis is a progressive central nervous system disease that affects the myelin, the protective covering of nerve fibers. This leads to various symptoms including weakness, vision loss, fatigue, and impaired coordination. Tinnitus is a condition characterized by ringing in the ears, Ankylosis refers to the stiffening or fusion of joints, and Apraxia is a motor disorder that affects the ability to perform purposeful movements. Therefore, the correct answer is Multiple Sclerosis.

15. A disease meaning "fused joint" is called:

Ankylosis

Ataxia

Apraxia

Dyskinesia

Ankylosis is a medical term that refers to the condition of a fused joint. The term "ankylosis" is derived from the Greek word "ankylos," meaning "crooked" or "bent." In this condition, the affected joint becomes stiff and immobile due to the fusion of the bones. This can be caused by various factors such as inflammation, injury, or disease. Ankylosis commonly occurs in conditions like arthritis or as a result of joint infection. It can significantly limit the range of motion and cause pain and discomfort.

Explanation

Ankylosis is a medical term that refers to the condition of a fused joint. The term "ankylosis" is derived from the Greek word "ankylos," meaning "crooked" or "bent." In this condition, the affected joint becomes stiff and immobile due to the fusion of the bones. This can be caused by various factors such as inflammation, injury, or disease. Ankylosis commonly occurs in conditions like arthritis or as a result of joint infection. It can significantly limit the range of motion and cause pain and discomfort.

16. When should hands be washed?

Before and after contact with every patient

Before contact with every patient

After contact with every patient

Arrival to the operating rooms

Hands should be washed before and after contact with every patient to prevent the spread of germs and infections. Washing hands before contact with a patient helps to remove any potential pathogens that may be present on the hands, reducing the risk of transmitting them to the patient. Washing hands after contact with a patient helps to remove any pathogens that may have been acquired during the interaction, preventing their spread to other patients or healthcare workers. This practice is essential in maintaining proper hygiene and preventing healthcare-associated infections.

Explanation

Hands should be washed before and after contact with every patient to prevent the spread of germs and infections. Washing hands before contact with a patient helps to remove any potential pathogens that may be present on the hands, reducing the risk of transmitting them to the patient. Washing hands after contact with a patient helps to remove any pathogens that may have been acquired during the interaction, preventing their spread to other patients or healthcare workers. This practice is essential in maintaining proper hygiene and preventing healthcare-associated infections.

17. A direct activation of corticospinal tract produces a D-Wave.

True

False

When the corticospinal tract is directly activated, it results in the production of a D-Wave. This suggests that the statement is true. The corticospinal tract is responsible for transmitting signals from the motor cortex to the spinal cord, which then controls voluntary movements. Activation of this pathway can be measured using a technique called transcranial magnetic stimulation (TMS), which produces a characteristic waveform known as the D-Wave. This waveform represents the activation of the corticospinal tract and is commonly used in studies investigating motor function and cortical excitability.

Explanation

When the corticospinal tract is directly activated, it results in the production of a D-Wave. This suggests that the statement is true. The corticospinal tract is responsible for transmitting signals from the motor cortex to the spinal cord, which then controls voluntary movements. Activation of this pathway can be measured using a technique called transcranial magnetic stimulation (TMS), which produces a characteristic waveform known as the D-Wave. This waveform represents the activation of the corticospinal tract and is commonly used in studies investigating motor function and cortical excitability.

18. The short acting muscle relaxant often given for intubation is:

Succinylcholine

Sevoflurane

Propofol

Rocuronium

Succinylcholine is often given for intubation because it is a short-acting muscle relaxant. It works by blocking the transmission of nerve impulses to the muscles, leading to temporary paralysis. This allows for easier intubation by reducing muscle tone and preventing patient movement during the procedure. Sevoflurane is a volatile anesthetic, Propofol is a sedative, and Rocuronium is a non-depolarizing muscle relaxant, none of which are specifically indicated for intubation.

Explanation

Succinylcholine is often given for intubation because it is a short-acting muscle relaxant. It works by blocking the transmission of nerve impulses to the muscles, leading to temporary paralysis. This allows for easier intubation by reducing muscle tone and preventing patient movement during the procedure. Sevoflurane is a volatile anesthetic, Propofol is a sedative, and Rocuronium is a non-depolarizing muscle relaxant, none of which are specifically indicated for intubation.

19. Stimulation of the motor roots of Trigeminal nerve (CN V) produces a muscle response from:

Masseter

Superior oblique

Inferior oblique

Frontalis

Stimulation of the motor roots of the Trigeminal nerve (CN V) produces a muscle response from the Masseter. The Trigeminal nerve is responsible for the motor function of the muscles involved in chewing, including the Masseter muscle. Stimulation of the motor roots of CN V would therefore cause contraction of the Masseter muscle, leading to a muscle response. The Superior oblique, Inferior oblique, and Frontalis muscles are not innervated by the Trigeminal nerve, so they would not produce a muscle response in this scenario.

Explanation

Stimulation of the motor roots of the Trigeminal nerve (CN V) produces a muscle response from the Masseter. The Trigeminal nerve is responsible for the motor function of the muscles involved in chewing, including the Masseter muscle. Stimulation of the motor roots of CN V would therefore cause contraction of the Masseter muscle, leading to a muscle response. The Superior oblique, Inferior oblique, and Frontalis muscles are not innervated by the Trigeminal nerve, so they would not produce a muscle response in this scenario.

20. EMG monitoring from the S3 root must include which muscle?

Anal Sphincter

Tibialis Anterior

Flexor Digitorum Longus

Gastrocnemius

EMG monitoring from the S3 root must include the Anal Sphincter muscle. This is because the S3 root is responsible for innervating the muscles of the pelvic floor, including the Anal Sphincter. Monitoring the EMG activity of the Anal Sphincter can provide valuable information about the function and integrity of the S3 nerve root and the pelvic floor muscles.

Explanation

EMG monitoring from the S3 root must include the Anal Sphincter muscle. This is because the S3 root is responsible for innervating the muscles of the pelvic floor, including the Anal Sphincter. Monitoring the EMG activity of the Anal Sphincter can provide valuable information about the function and integrity of the S3 nerve root and the pelvic floor muscles.

21. If the patients signals are lost and recovered during the surgery what will be the post operative outcome?

Full neurological recovery

Postoperative deficits

Partial neurological recovery

No neurological recovery

If the patients signals are lost and recovered during the surgery, it suggests that there was a temporary interruption in the patient's neurological function. However, since the signals were eventually recovered, it indicates that the patient's nervous system was able to regain full functionality. Therefore, the post-operative outcome in this case would be full neurological recovery.

Explanation

If the patients signals are lost and recovered during the surgery, it suggests that there was a temporary interruption in the patient's neurological function. However, since the signals were eventually recovered, it indicates that the patient's nervous system was able to regain full functionality. Therefore, the post-operative outcome in this case would be full neurological recovery.

22. The primary motor area is located where in the brain?

Anterior to the central sulcus

Posterior to the central sulcus

Lateral to the central sulcus

Inferior to the central sulcus

The primary motor area is located anterior to the central sulcus. This area, also known as the precentral gyrus, is responsible for controlling voluntary movements of the body. It is part of the frontal lobe and is involved in planning, initiating, and executing movements. The central sulcus divides the frontal lobe from the parietal lobe, and the primary motor area is situated in the frontal lobe in front of this sulcus.

Explanation

The primary motor area is located anterior to the central sulcus. This area, also known as the precentral gyrus, is responsible for controlling voluntary movements of the body. It is part of the frontal lobe and is involved in planning, initiating, and executing movements. The central sulcus divides the frontal lobe from the parietal lobe, and the primary motor area is situated in the frontal lobe in front of this sulcus.

23. An indirect activation of corticospinal tract produces an I-Wave.

True

False

An I-Wave is produced when there is an indirect activation of the corticospinal tract. This means that the corticospinal tract is not directly stimulated, but rather activated through other neural pathways. This indirect activation can occur through various mechanisms, such as transcranial magnetic stimulation or electrical stimulation of other brain regions. Therefore, the statement that an indirect activation of the corticospinal tract produces an I-Wave is true.

Explanation

An I-Wave is produced when there is an indirect activation of the corticospinal tract. This means that the corticospinal tract is not directly stimulated, but rather activated through other neural pathways. This indirect activation can occur through various mechanisms, such as transcranial magnetic stimulation or electrical stimulation of other brain regions. Therefore, the statement that an indirect activation of the corticospinal tract produces an I-Wave is true.

24. Occipital lobe is responsible for processing which evoked response?

Visual

Motor

Sensory

Hearing

The occipital lobe is responsible for processing visual information. It receives and interprets signals from the eyes, allowing us to see and perceive the world around us. This lobe plays a crucial role in visual perception, object recognition, and spatial awareness. It contains the primary visual cortex, which is responsible for the initial processing of visual stimuli. Therefore, the correct answer is visual.

Explanation

The occipital lobe is responsible for processing visual information. It receives and interprets signals from the eyes, allowing us to see and perceive the world around us. This lobe plays a crucial role in visual perception, object recognition, and spatial awareness. It contains the primary visual cortex, which is responsible for the initial processing of visual stimuli. Therefore, the correct answer is visual.

25. Mapping of the language area is done by stimulating which areas of the cortex?

Broca’s and Wernicke’s areas

Romberg’s and Wernicke’s areas

Broca’s and Hoffman’s areas

Hoffman’s and Romberg’s areas

The mapping of the language area is done by stimulating Broca's and Wernicke's areas. These areas are known to be involved in language processing and production. Stimulation of these areas can help identify the specific regions responsible for language functions and provide insights into language-related disorders and impairments.

Explanation

The mapping of the language area is done by stimulating Broca's and Wernicke's areas. These areas are known to be involved in language processing and production. Stimulation of these areas can help identify the specific regions responsible for language functions and provide insights into language-related disorders and impairments.

26. What is the electrical line frequency in the operating rooms in the USA?

60Hz

50Hz

70Hz

40Hz

The electrical line frequency in operating rooms in the USA is 60Hz. This frequency is the standard for electrical power systems in North America, including the United States. It refers to the number of cycles per second that alternating current (AC) electricity completes in a power system. The 60Hz frequency ensures the proper functioning of electrical equipment and devices used in operating rooms, providing a stable and reliable power supply.

Explanation

The electrical line frequency in operating rooms in the USA is 60Hz. This frequency is the standard for electrical power systems in North America, including the United States. It refers to the number of cycles per second that alternating current (AC) electricity completes in a power system. The 60Hz frequency ensures the proper functioning of electrical equipment and devices used in operating rooms, providing a stable and reliable power supply.

27. Where is the best place to put a ground electrode in order to reduce any stimulation artifact.

Between stimulation and recording electrodes

Before stimulation and recording electrodes

After stimulation and recording electrodes

Depends on how much artifact is present

The best place to put a ground electrode in order to reduce any stimulation artifact is between the stimulation and recording electrodes. Placing the ground electrode in this position helps to minimize the interference caused by the stimulation, as it provides a direct pathway for the electrical current to flow and prevents it from affecting the recording electrodes. This placement ensures that the artifact is reduced and the recorded signals are more accurate.

Explanation

The best place to put a ground electrode in order to reduce any stimulation artifact is between the stimulation and recording electrodes. Placing the ground electrode in this position helps to minimize the interference caused by the stimulation, as it provides a direct pathway for the electrical current to flow and prevents it from affecting the recording electrodes. This placement ensures that the artifact is reduced and the recorded signals are more accurate.

28. The first component of BAER does not arise in the brainstem but the auditory nerve.

True

False

The first component of BAER, which stands for Brainstem Auditory Evoked Response, does not originate in the brainstem but in the auditory nerve. This means that the initial response to auditory stimuli is generated in the auditory nerve before it reaches the brainstem for further processing. This distinction is important in understanding the pathway of auditory information and how it is transmitted from the ear to the brain.

Explanation

The first component of BAER, which stands for Brainstem Auditory Evoked Response, does not originate in the brainstem but in the auditory nerve. This means that the initial response to auditory stimuli is generated in the auditory nerve before it reaches the brainstem for further processing. This distinction is important in understanding the pathway of auditory information and how it is transmitted from the ear to the brain.

29. Which intravenous anesthetic agents cause an increase in amplitude of SSEP & TcMEP responses?

Ketamine & Etomidate

Propofol & Sevoflurane

Remifentanil & Etomidate

Ketamine & Propofol

Ketamine and Etomidate are intravenous anesthetic agents that cause an increase in amplitude of SSEP (Somatosensory Evoked Potentials) and TcMEP (Transcranial Motor Evoked Potentials) responses. SSEP measures the electrical activity in the brain in response to sensory stimulation, while TcMEP measures the electrical activity in the muscles in response to motor stimulation. The increase in amplitude of these responses indicates enhanced neural activity, suggesting that Ketamine and Etomidate have excitatory effects on the central nervous system.

Explanation

Ketamine and Etomidate are intravenous anesthetic agents that cause an increase in amplitude of SSEP (Somatosensory Evoked Potentials) and TcMEP (Transcranial Motor Evoked Potentials) responses. SSEP measures the electrical activity in the brain in response to sensory stimulation, while TcMEP measures the electrical activity in the muscles in response to motor stimulation. The increase in amplitude of these responses indicates enhanced neural activity, suggesting that Ketamine and Etomidate have excitatory effects on the central nervous system.

30. Which one of the following agents is an opioid:

Fentanyl

Methohexital

Vecuronium

Sevoflurane

Fentanyl is classified as an opioid because it is a synthetic narcotic analgesic that acts on the opioid receptors in the brain and spinal cord. It is commonly used for pain management, particularly for severe or chronic pain. Fentanyl is much stronger than other opioids like morphine and is often used in medical settings for anesthesia during surgery or for managing pain in cancer patients. It can also be misused recreationally due to its powerful effects, which can lead to addiction and overdose.

Explanation

Fentanyl is classified as an opioid because it is a synthetic narcotic analgesic that acts on the opioid receptors in the brain and spinal cord. It is commonly used for pain management, particularly for severe or chronic pain. Fentanyl is much stronger than other opioids like morphine and is often used in medical settings for anesthesia during surgery or for managing pain in cancer patients. It can also be misused recreationally due to its powerful effects, which can lead to addiction and overdose.

31. What anesthetics are contraindicated when monitoring TcMEP?

Muscle relaxants

Barbiturates

Opioids

Inhalationals

Muscle relaxants are contraindicated when monitoring TcMEP (Transcranial Motor Evoked Potentials) because they can interfere with the measurement of muscle responses. TcMEP is a technique used to monitor the integrity of the motor pathways during surgery, and muscle relaxants can inhibit or suppress the muscle responses, making it difficult to accurately assess the function of the motor pathways. Therefore, it is important to avoid using muscle relaxants when performing TcMEP monitoring.

Explanation

Muscle relaxants are contraindicated when monitoring TcMEP (Transcranial Motor Evoked Potentials) because they can interfere with the measurement of muscle responses. TcMEP is a technique used to monitor the integrity of the motor pathways during surgery, and muscle relaxants can inhibit or suppress the muscle responses, making it difficult to accurately assess the function of the motor pathways. Therefore, it is important to avoid using muscle relaxants when performing TcMEP monitoring.

32. A reponse recorded by an epidural electrode due to direct activation of corticospinal tract is known as:

D-Wave

I-Wave

Subcorticals

Corticals

A response recorded by an epidural electrode due to direct activation of the corticospinal tract is known as a D-Wave.

Explanation

A response recorded by an epidural electrode due to direct activation of the corticospinal tract is known as a D-Wave.

33. A forward movement of lumbar vertebrae over the vertebrae one level below is known as:

Spondylolisthesis

Spondylitis

Sublaxation

Spina bifida

Spondylolisthesis is the correct answer because it refers to the forward movement of lumbar vertebrae over the vertebrae one level below. This condition can occur due to a fracture or defect in the pars interarticularis, a small bony segment connecting the facet joints in the back of the spine. It can cause lower back pain, leg pain, and weakness. Spondylitis is inflammation of the spine, subluxation is a partial dislocation of a joint, and spina bifida is a birth defect where the spinal cord does not fully develop.

Explanation

Spondylolisthesis is the correct answer because it refers to the forward movement of lumbar vertebrae over the vertebrae one level below. This condition can occur due to a fracture or defect in the pars interarticularis, a small bony segment connecting the facet joints in the back of the spine. It can cause lower back pain, leg pain, and weakness. Spondylitis is inflammation of the spine, subluxation is a partial dislocation of a joint, and spina bifida is a birth defect where the spinal cord does not fully develop.

34. We usually see after discharges (Ads) at which stage?

After direct cortical motor stimulation

Before direct cortical motor stimulation

After direct cortical sensory stimulation

Before direct cortical sensory stimulation

After direct cortical motor stimulation, we usually see after discharges (Ads). This means that after the motor cortex is stimulated, there is a continuation of neural activity in the form of after discharges. These after discharges can be observed as prolonged electrical activity in the brain after the initial stimulation.

Explanation

After direct cortical motor stimulation, we usually see after discharges (Ads). This means that after the motor cortex is stimulated, there is a continuation of neural activity in the form of after discharges. These after discharges can be observed as prolonged electrical activity in the brain after the initial stimulation.

35. If TOF is done from the posterior tibial nerve at the ankle which muscle will be ideal for recording?

Abductor hallucis brevis (AHB)

Flexor digitorum profundus (FDP)

Tibialis anterior (TA)

Tibialis posterior (TP)

When performing TOF (tibial nerve somatosensory evoked potential) from the posterior tibial nerve at the ankle, the ideal muscle for recording is the Abductor hallucis brevis (AHB). The AHB muscle is innervated by the medial plantar nerve, which branches off from the posterior tibial nerve. Therefore, recording the response from the AHB muscle will provide the most accurate and reliable measurement of the tibial nerve's function in this specific test.

Explanation

When performing TOF (tibial nerve somatosensory evoked potential) from the posterior tibial nerve at the ankle, the ideal muscle for recording is the Abductor hallucis brevis (AHB). The AHB muscle is innervated by the medial plantar nerve, which branches off from the posterior tibial nerve. Therefore, recording the response from the AHB muscle will provide the most accurate and reliable measurement of the tibial nerve's function in this specific test.

36. If the surgeon's arm touches the IOM equipment table, it will become unsterile.

True

False

The statement suggests that if the surgeon's arm comes into contact with the IOM equipment table, it will lose its sterility. This implies that the IOM equipment table is considered a sterile area, and any contact with it can compromise the sterility of the surgeon's arm. Therefore, the answer is true.

Explanation

The statement suggests that if the surgeon's arm comes into contact with the IOM equipment table, it will lose its sterility. This implies that the IOM equipment table is considered a sterile area, and any contact with it can compromise the sterility of the surgeon's arm. Therefore, the answer is true.

37. Which cranial nerves should be monitored for a cerebellopontine angle (CPA) tumor less than 2 cm in size?

CN VII and CN VIII

CN V

CN X

CN II, CN III, CN IV

A cerebellopontine angle (CPA) tumor is a growth that occurs in the space between the cerebellum and the pons. This area is where cranial nerves VII (facial nerve) and VIII (vestibulocochlear nerve) are located. These two cranial nerves are responsible for important functions such as facial movement, hearing, and balance. Monitoring these nerves is crucial when dealing with a CPA tumor, as the tumor can potentially compress or damage these nerves, leading to various neurological symptoms. Therefore, CN VII and CN VIII should be monitored in cases of CPA tumors less than 2 cm in size.

Explanation

A cerebellopontine angle (CPA) tumor is a growth that occurs in the space between the cerebellum and the pons. This area is where cranial nerves VII (facial nerve) and VIII (vestibulocochlear nerve) are located. These two cranial nerves are responsible for important functions such as facial movement, hearing, and balance. Monitoring these nerves is crucial when dealing with a CPA tumor, as the tumor can potentially compress or damage these nerves, leading to various neurological symptoms. Therefore, CN VII and CN VIII should be monitored in cases of CPA tumors less than 2 cm in size.

38. During a continuous cautery what should we do with the recording?

Pause the recording

Delete the recording

Continue recording

Ignore the recording

During a continuous cautery, it is necessary to pause the recording. This is because cautery involves the use of heat to cut or coagulate tissue, which can generate electrical interference that may disrupt the recording. By pausing the recording, any potential interference can be minimized, ensuring accurate and reliable data collection.

Explanation

During a continuous cautery, it is necessary to pause the recording. This is because cautery involves the use of heat to cut or coagulate tissue, which can generate electrical interference that may disrupt the recording. By pausing the recording, any potential interference can be minimized, ensuring accurate and reliable data collection.

39. The electrode impedance can be measured using what device?

Ohmmeter

Amplimeter

Voltmeter

Electrometer

An ohmmeter is used to measure the resistance of a circuit or component, which is directly related to the impedance of the electrode. Impedance is the overall opposition to the flow of alternating current in a circuit, and it includes both resistance and reactance. Since an ohmmeter is specifically designed to measure resistance, it is the most appropriate device to measure electrode impedance. Amplimeter, voltmeter, and electrometer are not specifically designed for measuring resistance and may not provide accurate impedance measurements.

Explanation

An ohmmeter is used to measure the resistance of a circuit or component, which is directly related to the impedance of the electrode. Impedance is the overall opposition to the flow of alternating current in a circuit, and it includes both resistance and reactance. Since an ohmmeter is specifically designed to measure resistance, it is the most appropriate device to measure electrode impedance. Amplimeter, voltmeter, and electrometer are not specifically designed for measuring resistance and may not provide accurate impedance measurements.

40. The machine used in the operating room that causes suction, washes, and filters blood so it can be given to the patient is called a:

Cell saver

Hot line

Blood bank

Drain

A cell saver is a machine used in the operating room that suctions, washes, and filters blood so that it can be given back to the patient. This machine is commonly used during surgeries where there is a high risk of blood loss. By recycling the patient's own blood, the cell saver helps to minimize the need for blood transfusions and reduces the risk of complications associated with receiving donated blood.

Explanation

A cell saver is a machine used in the operating room that suctions, washes, and filters blood so that it can be given back to the patient. This machine is commonly used during surgeries where there is a high risk of blood loss. By recycling the patient's own blood, the cell saver helps to minimize the need for blood transfusions and reduces the risk of complications associated with receiving donated blood.

41. If it not possible to stimulate the posterior tibial nerve, which nerve should be used as an alternate?

Peroneal Nerve

Sciatic Nerve

Femoral Nerve

Sural Nerve

If it is not possible to stimulate the posterior tibial nerve, the peroneal nerve can be used as an alternate. The peroneal nerve is a branch of the sciatic nerve and runs along the outer side of the lower leg. It innervates the muscles that control foot dorsiflexion and eversion. By stimulating the peroneal nerve, similar effects can be achieved as stimulating the posterior tibial nerve, allowing for alternative nerve stimulation in cases where the posterior tibial nerve cannot be stimulated.

Explanation

If it is not possible to stimulate the posterior tibial nerve, the peroneal nerve can be used as an alternate. The peroneal nerve is a branch of the sciatic nerve and runs along the outer side of the lower leg. It innervates the muscles that control foot dorsiflexion and eversion. By stimulating the peroneal nerve, similar effects can be achieved as stimulating the posterior tibial nerve, allowing for alternative nerve stimulation in cases where the posterior tibial nerve cannot be stimulated.

42. The C5 nerve root innervates which muscles?

Deltoid

Tricep

Trapezius

None of the above

The C5 nerve root innervates the deltoid muscle. This means that the C5 nerve supplies the signals for the movement and sensation of the deltoid muscle. The tricep and trapezius muscles are not innervated by the C5 nerve root. Therefore, the correct answer is Deltoid.

Explanation

The C5 nerve root innervates the deltoid muscle. This means that the C5 nerve supplies the signals for the movement and sensation of the deltoid muscle. The tricep and trapezius muscles are not innervated by the C5 nerve root. Therefore, the correct answer is Deltoid.

43. Lower limb SSEPs are transmitted via:

Fasciculus Gracilis

Fasciculus Cuneatus

Nucleus Cuneatus

Cauda Equina

Lower limb SSEPs are transmitted via the Fasciculus Gracilis. This is a specific pathway in the spinal cord that carries sensory information from the lower limbs to the brain. The Fasciculus Gracilis is responsible for transmitting proprioceptive and fine touch sensations from the lower limbs, allowing us to perceive and interpret sensory information from our legs and feet.

Explanation

Lower limb SSEPs are transmitted via the Fasciculus Gracilis. This is a specific pathway in the spinal cord that carries sensory information from the lower limbs to the brain. The Fasciculus Gracilis is responsible for transmitting proprioceptive and fine touch sensations from the lower limbs, allowing us to perceive and interpret sensory information from our legs and feet.

44. What is the blood supply of cortical responses elicited by median nerve stimulation?

MCA: Middle cerebral artery

ACA: Anterior cerebral artery

VBA: Veterbo-Basilar artery

FA: Femoral artery

The correct answer is MCA: Middle cerebral artery. The blood supply of cortical responses elicited by median nerve stimulation is provided by the middle cerebral artery. This artery supplies blood to the lateral surface of the cerebral hemisphere, including the primary motor and sensory cortices. Stimulation of the median nerve leads to the activation of these cortical areas, and the blood supply from the middle cerebral artery ensures the delivery of oxygen and nutrients to support this neural activity.

Explanation

The correct answer is MCA: Middle cerebral artery. The blood supply of cortical responses elicited by median nerve stimulation is provided by the middle cerebral artery. This artery supplies blood to the lateral surface of the cerebral hemisphere, including the primary motor and sensory cortices. Stimulation of the median nerve leads to the activation of these cortical areas, and the blood supply from the middle cerebral artery ensures the delivery of oxygen and nutrients to support this neural activity.

45. Neuromuscular blocking agents can be helpful in recording of:

SSEP

EMG

TcMEP

TOF

Neuromuscular blocking agents can be helpful in recording SSEP (Somatosensory Evoked Potentials). These agents temporarily paralyze the muscles, allowing for more accurate and reliable recordings of the electrical signals generated by the sensory nerves in response to a stimulus. This paralysis prevents any interference or movement artifacts that may occur during the recording process, ensuring better quality and interpretation of the SSEP results.

Explanation

Neuromuscular blocking agents can be helpful in recording SSEP (Somatosensory Evoked Potentials). These agents temporarily paralyze the muscles, allowing for more accurate and reliable recordings of the electrical signals generated by the sensory nerves in response to a stimulus. This paralysis prevents any interference or movement artifacts that may occur during the recording process, ensuring better quality and interpretation of the SSEP results.

46. Compression or sustained traction of a nerve appears in spontaneous EMG recordings as a:

Train response

Burst response

No response

Spike response

Compression or sustained traction of a nerve can cause abnormal electrical activity in the nerve, which can be detected in EMG recordings. This abnormal activity is characterized by a series of repetitive, closely spaced muscle fiber action potentials, resembling a train of responses. Therefore, the correct answer is "Train response".

Explanation

Compression or sustained traction of a nerve can cause abnormal electrical activity in the nerve, which can be detected in EMG recordings. This abnormal activity is characterized by a series of repetitive, closely spaced muscle fiber action potentials, resembling a train of responses. Therefore, the correct answer is "Train response".

47. Pedicle screws are placed in order to perform what procedure?

Spinal fixation

Anterior lumbar interbody fusion

Kyphoplasty

Corpectomy

Pedicle screws are placed in order to perform spinal fixation. This procedure involves the placement of screws into the pedicles of the vertebrae to provide stability and support to the spine. It is commonly used in the treatment of spinal deformities, fractures, and spinal fusions. The pedicle screws are inserted into the vertebral bodies and connected with rods or plates to immobilize the spine, allowing for fusion and healing. This helps to correct spinal alignment, relieve pain, and prevent further damage to the spine.

Explanation

Pedicle screws are placed in order to perform spinal fixation. This procedure involves the placement of screws into the pedicles of the vertebrae to provide stability and support to the spine. It is commonly used in the treatment of spinal deformities, fractures, and spinal fusions. The pedicle screws are inserted into the vertebral bodies and connected with rods or plates to immobilize the spine, allowing for fusion and healing. This helps to correct spinal alignment, relieve pain, and prevent further damage to the spine.

48. Bloodborne pathogens may cause which of the following diseases:

Asthma

Cystic fibrosis

Hepatitis B

TB

Bloodborne pathogens are infectious microorganisms that are present in the blood and can cause diseases when transmitted from one person to another through exposure to infected blood. Hepatitis B is a viral infection caused by the hepatitis B virus (HBV) and is one of the diseases that can be transmitted through bloodborne pathogens. It affects the liver and can lead to chronic liver disease, liver cancer, and even death if left untreated. Asthma and cystic fibrosis are not caused by bloodborne pathogens, while TB (tuberculosis) is primarily transmitted through the air and not through blood. Therefore, the correct answer is Hepatitis B.

Explanation

Bloodborne pathogens are infectious microorganisms that are present in the blood and can cause diseases when transmitted from one person to another through exposure to infected blood. Hepatitis B is a viral infection caused by the hepatitis B virus (HBV) and is one of the diseases that can be transmitted through bloodborne pathogens. It affects the liver and can lead to chronic liver disease, liver cancer, and even death if left untreated. Asthma and cystic fibrosis are not caused by bloodborne pathogens, while TB (tuberculosis) is primarily transmitted through the air and not through blood. Therefore, the correct answer is Hepatitis B.

49. The part of the spine removed to place an epidural electrode is known as:

Lamina

Vertebral body

Foramen

Intervertebral disc

The lamina is the part of the spine that is removed in order to place an epidural electrode. The lamina is a thin, flat bone that forms the back part of the spinal canal. By removing the lamina, the surgeon can access the epidural space and place the electrode for pain management or other purposes. The other options listed, such as the vertebral body, foramen, and intervertebral disc, are not directly involved in the placement of an epidural electrode.

Explanation

The lamina is the part of the spine that is removed in order to place an epidural electrode. The lamina is a thin, flat bone that forms the back part of the spinal canal. By removing the lamina, the surgeon can access the epidural space and place the electrode for pain management or other purposes. The other options listed, such as the vertebral body, foramen, and intervertebral disc, are not directly involved in the placement of an epidural electrode.

50. Which cranial nerve function will be compromised by the disease called "Bell's Palsy"?

Facial (CN VII)

Trigeminal (CN V)

Vagus (CN X)

Spinal Accessory (CN XI)

Bell's Palsy is a condition that causes temporary weakness or paralysis of the muscles on one side of the face. The facial nerve (CN VII) controls the muscles of facial expression, including smiling, frowning, and closing the eyes. Therefore, when someone has Bell's Palsy, the function of the facial nerve (CN VII) is compromised, leading to the characteristic facial drooping on one side.

Explanation

Bell's Palsy is a condition that causes temporary weakness or paralysis of the muscles on one side of the face. The facial nerve (CN VII) controls the muscles of facial expression, including smiling, frowning, and closing the eyes. Therefore, when someone has Bell's Palsy, the function of the facial nerve (CN VII) is compromised, leading to the characteristic facial drooping on one side.

51. An interbody cage is placed to:

Restore the height of lost disc space

Take pressure off of compressed nerve roots

Fuse two or more vertebral bodies together

Protect the spinal cord in place of the lamina

An interbody cage is a device used in spinal surgery to restore the height of a lost disc space. When a disc in the spine degenerates or is damaged, it can lead to a loss of disc height, causing instability and compression of nearby nerves. By placing an interbody cage in the disc space, it helps to restore the height and alignment of the spine, reducing pressure on the nerves and promoting fusion between the vertebral bodies. This helps to alleviate pain, improve stability, and restore normal function in the spine.

Explanation

An interbody cage is a device used in spinal surgery to restore the height of a lost disc space. When a disc in the spine degenerates or is damaged, it can lead to a loss of disc height, causing instability and compression of nearby nerves. By placing an interbody cage in the disc space, it helps to restore the height and alignment of the spine, reducing pressure on the nerves and promoting fusion between the vertebral bodies. This helps to alleviate pain, improve stability, and restore normal function in the spine.

52. What is the probable cause of noise if it is observed in all channels?

Poor ground electrode

Leakage current

Input impedance

CMRR

A poor ground electrode can be the probable cause of noise in all channels. A ground electrode is responsible for providing a stable reference point for electrical signals. If the ground electrode is poor, it can result in an unstable or noisy ground, causing interference in all channels. This can lead to distorted or unclear signals, affecting the overall quality of the audio or video being transmitted.

Explanation

A poor ground electrode can be the probable cause of noise in all channels. A ground electrode is responsible for providing a stable reference point for electrical signals. If the ground electrode is poor, it can result in an unstable or noisy ground, causing interference in all channels. This can lead to distorted or unclear signals, affecting the overall quality of the audio or video being transmitted.

53. An inflammation of a vertebrae or vertebral joint is known as:

Spondylitis

Spondylolisthesis

Sublaxation

Spina bifida

Spondylitis refers to the inflammation of a vertebrae or vertebral joint. This condition can cause pain, stiffness, and swelling in the affected area. It is often caused by an infection or an autoimmune disease such as ankylosing spondylitis. Treatment for spondylitis may include medication, physical therapy, and lifestyle modifications to manage pain and improve mobility.

Explanation

Spondylitis refers to the inflammation of a vertebrae or vertebral joint. This condition can cause pain, stiffness, and swelling in the affected area. It is often caused by an infection or an autoimmune disease such as ankylosing spondylitis. Treatment for spondylitis may include medication, physical therapy, and lifestyle modifications to manage pain and improve mobility.

54. The warning criteria for SSEP changes have been generally accepted as: Which one do you like?

50% decrease in amplitude and/or 10% increase in latency

50% increase in amplitude and/or 10% increase in latency

10% decrease in amplitude and/or 50% increase in latency

50% decrease in amplitude and/or 10% decrease in latency

The correct answer is 50% decrease in amplitude and/or 10% increase in latency. This means that if there is a 50% decrease in the amplitude of the SSEP signal or a 10% increase in the latency (delay) of the signal, it is considered a warning criteria for SSEP changes. These changes may indicate a potential problem or abnormality in the sensory evoked potentials.

Explanation

The correct answer is 50% decrease in amplitude and/or 10% increase in latency. This means that if there is a 50% decrease in the amplitude of the SSEP signal or a 10% increase in the latency (delay) of the signal, it is considered a warning criteria for SSEP changes. These changes may indicate a potential problem or abnormality in the sensory evoked potentials.

55. Obligatory waves of the posterior tibial nerve (PTN) are:

PF, LP, P31, N34, & P37

EP, LP, P31, N34, & P37

N9, N13, P14, N18, & N20

EP, N13, P14, N18, & N20

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Explanation

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56. A selective dorsal root rhizotomy is used for the treatment of:

Spasticity

Pain

Weakness

Numbness

Selective dorsal root rhizotomy is a surgical procedure used to treat spasticity. Spasticity is a condition characterized by muscle stiffness and tightness, often caused by damage to the brain or spinal cord. This procedure involves selectively cutting certain nerve roots in the spinal cord to reduce the abnormal signals that cause spasticity. By targeting and eliminating these abnormal signals, selective dorsal root rhizotomy can help improve muscle function and reduce spasticity in patients.

Explanation

Selective dorsal root rhizotomy is a surgical procedure used to treat spasticity. Spasticity is a condition characterized by muscle stiffness and tightness, often caused by damage to the brain or spinal cord. This procedure involves selectively cutting certain nerve roots in the spinal cord to reduce the abnormal signals that cause spasticity. By targeting and eliminating these abnormal signals, selective dorsal root rhizotomy can help improve muscle function and reduce spasticity in patients.

57. The areas of the skin supplied by cutaneous branches of the spinal nerves are known as:

Dermatomes

White Matter

Grey Matter

Myelin Sheaths

Dermatomes refer to the specific areas of the skin that are innervated by the sensory branches of the spinal nerves. Each spinal nerve innervates a specific dermatome, which allows for the sensation of touch, pain, and temperature in that particular area. This term is commonly used in medical fields, such as neurology and orthopedics, to identify and diagnose nerve-related conditions or injuries based on the affected dermatome.

Explanation

Dermatomes refer to the specific areas of the skin that are innervated by the sensory branches of the spinal nerves. Each spinal nerve innervates a specific dermatome, which allows for the sensation of touch, pain, and temperature in that particular area. This term is commonly used in medical fields, such as neurology and orthopedics, to identify and diagnose nerve-related conditions or injuries based on the affected dermatome.

58. Upper limb SSEPs are transmitted via:

Fasciculus Cuneatus

Fasciculus Gracilis

Nucleus Gracilis

Corticospinal Fibers

Upper limb somatosensory evoked potentials (SSEPs) are transmitted via the fasciculus cuneatus. The fasciculus cuneatus is a white matter tract in the spinal cord that carries sensory information from the upper limbs to the brain. It is responsible for transmitting touch, vibration, and proprioceptive information from the upper limbs to the somatosensory cortex. The other options, including the fasciculus gracilis, nucleus gracilis, and corticospinal fibers, are not involved in the transmission of upper limb SSEPs.

Explanation

Upper limb somatosensory evoked potentials (SSEPs) are transmitted via the fasciculus cuneatus. The fasciculus cuneatus is a white matter tract in the spinal cord that carries sensory information from the upper limbs to the brain. It is responsible for transmitting touch, vibration, and proprioceptive information from the upper limbs to the somatosensory cortex. The other options, including the fasciculus gracilis, nucleus gracilis, and corticospinal fibers, are not involved in the transmission of upper limb SSEPs.

59. EMG monitoring from the S1 root muscle include which muscle?

Gastrocnemius

Anal sphincter

Tibialis anterior

Rectus femoris

EMG monitoring from the S1 root muscle includes the gastrocnemius muscle. The S1 root is part of the sacral plexus, which innervates the lower limb muscles. The gastrocnemius muscle is located in the calf and is responsible for plantar flexion of the foot. By monitoring the EMG activity in the gastrocnemius muscle, clinicians can assess the function and activity of the S1 root and evaluate any abnormalities or dysfunction.

Explanation

EMG monitoring from the S1 root muscle includes the gastrocnemius muscle. The S1 root is part of the sacral plexus, which innervates the lower limb muscles. The gastrocnemius muscle is located in the calf and is responsible for plantar flexion of the foot. By monitoring the EMG activity in the gastrocnemius muscle, clinicians can assess the function and activity of the S1 root and evaluate any abnormalities or dysfunction.

60. Which nerve should be stimulated for lower limb SSEP as recommended by ACNS guidelines for short-latency SSEP?

Posterior tibial nerve

Peroneal nerve

Sciatic nerve

Median nerve

The ACNS guidelines recommend stimulating the posterior tibial nerve for lower limb SSEP. This nerve is responsible for sensory innervation of the sole of the foot and its stimulation can provide accurate and reliable signals for assessing the function of the lower limb. Stimulation of the peroneal nerve, sciatic nerve, or median nerve would not be appropriate for lower limb SSEP as they do not specifically target the sensory innervation of the lower limb.

Explanation

The ACNS guidelines recommend stimulating the posterior tibial nerve for lower limb SSEP. This nerve is responsible for sensory innervation of the sole of the foot and its stimulation can provide accurate and reliable signals for assessing the function of the lower limb. Stimulation of the peroneal nerve, sciatic nerve, or median nerve would not be appropriate for lower limb SSEP as they do not specifically target the sensory innervation of the lower limb.

61. The N20 responses is generated from which structure?

The sensory cortex (contralateral to the stimulation side)

The sensory cortex (ipsilateral to the stimulation side)

The motor cortex (contralateral to the stimulation side)

The motor cortex (ipsilateral to the stimulation side)

The N20 responses are generated from the sensory cortex contralateral to the stimulation side. This means that when a stimulus is applied to one side of the body, the sensory information is processed in the sensory cortex on the opposite side of the brain.

Explanation

The N20 responses are generated from the sensory cortex contralateral to the stimulation side. This means that when a stimulus is applied to one side of the body, the sensory information is processed in the sensory cortex on the opposite side of the brain.

62. Lumbar Potential (LP) is a stationary (non-propagated) potential.

True

False

Lumbar Potential (LP) is a stationary potential, meaning it does not propagate or move from one place to another. This suggests that LP remains localized in the lumbar region and does not spread throughout the body. Therefore, the statement "Lumbar Potential (LP) is a stationary (non-propagated) potential" is true.

Explanation

Lumbar Potential (LP) is a stationary potential, meaning it does not propagate or move from one place to another. This suggests that LP remains localized in the lumbar region and does not spread throughout the body. Therefore, the statement "Lumbar Potential (LP) is a stationary (non-propagated) potential" is true.

63. Intraoperative facial nerve monitoring was a result of a high incidence of post operative facial nerve weakness after acoustic nerve surgeries.

True

False

Intraoperative facial nerve monitoring was developed in response to a high occurrence of facial nerve weakness after acoustic nerve surgeries. This monitoring technique allows surgeons to assess the function of the facial nerve in real-time during the surgery, helping to prevent or minimize nerve damage and potential post-operative complications.

Explanation

Intraoperative facial nerve monitoring was developed in response to a high occurrence of facial nerve weakness after acoustic nerve surgeries. This monitoring technique allows surgeons to assess the function of the facial nerve in real-time during the surgery, helping to prevent or minimize nerve damage and potential post-operative complications.

64. A microvascular decompression (MVD) of the cranial nerve is:

Placing a teflon pad between an artery and a nerve to separate the artery from the nerve

Placing a teflon pad between a muscle and a nerve to separate the artery from the nerve

Placing a nerve hook between the nerve to separate the artery from the nerve

Decompressing a cyst from the nerve

A microvascular decompression (MVD) is a surgical procedure that involves placing a teflon pad between an artery and a nerve to separate them. This is done to relieve pressure on the nerve caused by the artery. By separating the artery from the nerve, the compression on the nerve is alleviated, reducing symptoms such as pain or dysfunction. This procedure is commonly performed to treat conditions such as trigeminal neuralgia or hemifacial spasm.

Explanation

A microvascular decompression (MVD) is a surgical procedure that involves placing a teflon pad between an artery and a nerve to separate them. This is done to relieve pressure on the nerve caused by the artery. By separating the artery from the nerve, the compression on the nerve is alleviated, reducing symptoms such as pain or dysfunction. This procedure is commonly performed to treat conditions such as trigeminal neuralgia or hemifacial spasm.

65. TCD is used for measuring blood flow velocity not blood flow. True Which one do you like?

True

False

The statement is stating that TCD (Transcranial Doppler) is used for measuring blood flow velocity, not blood flow. This means that TCD is not able to measure the actual volume of blood flow, but rather the speed or velocity at which the blood is flowing. Therefore, the correct answer is "True" because it accurately reflects the information provided in the statement.

Explanation

The statement is stating that TCD (Transcranial Doppler) is used for measuring blood flow velocity, not blood flow. This means that TCD is not able to measure the actual volume of blood flow, but rather the speed or velocity at which the blood is flowing. Therefore, the correct answer is "True" because it accurately reflects the information provided in the statement.

66. In which procedure is lower extremity triggered EMG used to identify rootlets that can cause spasticity?

Selective dorsal rhizotomy

Oblique lateral interbody fusion

Lumbar corpectomy

Cauda equina decompression

Selective dorsal rhizotomy is the procedure in which lower extremity triggered EMG is used to identify rootlets that can cause spasticity. This procedure involves cutting selectively the sensory nerve fibers in the spinal cord that are responsible for transmitting abnormal signals to the muscles, thus reducing spasticity. By using triggered EMG, the surgeon can identify the specific rootlets that are causing the spasticity and selectively cut them, leading to improved motor function and reduced muscle stiffness.

Explanation

Selective dorsal rhizotomy is the procedure in which lower extremity triggered EMG is used to identify rootlets that can cause spasticity. This procedure involves cutting selectively the sensory nerve fibers in the spinal cord that are responsible for transmitting abnormal signals to the muscles, thus reducing spasticity. By using triggered EMG, the surgeon can identify the specific rootlets that are causing the spasticity and selectively cut them, leading to improved motor function and reduced muscle stiffness.

67. Which of the following structures is not part of the brainstem:

Cerebellum

Pons

Medulla

All of the above

The cerebellum is not part of the brainstem. The brainstem consists of three structures: the pons, medulla, and midbrain. The cerebellum is located above the brainstem and is responsible for coordinating movement, balance, and posture. While it is connected to the brainstem, it is considered a separate structure.

Explanation

The cerebellum is not part of the brainstem. The brainstem consists of three structures: the pons, medulla, and midbrain. The cerebellum is located above the brainstem and is responsible for coordinating movement, balance, and posture. While it is connected to the brainstem, it is considered a separate structure.

68. The ratio of an output voltage to an input voltage of the amplifier is known as:

Gain

Aliaising

Coulomb's law

Ohm's law

The ratio of an output voltage to an input voltage of an amplifier is known as gain. Gain is a measure of the amplification or multiplication factor of the input signal. It indicates how much the input signal is amplified by the amplifier. A higher gain value means a larger output voltage compared to the input voltage, while a lower gain value means a smaller output voltage compared to the input voltage. Therefore, gain is the correct answer in this context.

Explanation

The ratio of an output voltage to an input voltage of an amplifier is known as gain. Gain is a measure of the amplification or multiplication factor of the input signal. It indicates how much the input signal is amplified by the amplifier. A higher gain value means a larger output voltage compared to the input voltage, while a lower gain value means a smaller output voltage compared to the input voltage. Therefore, gain is the correct answer in this context.

69. If your amplifier gets saturated during the exposure part of the surgery, how should you solve it?

Reset the amplifier

Use another amplifier

Replace the power cable

Call biomed

If the amplifier gets saturated during the exposure part of the surgery, resetting the amplifier can be a possible solution. By resetting the amplifier, it can help to resolve any technical issues or errors that may have caused the saturation. This can help to restore the amplifier to its normal functioning state and ensure that it is able to accurately amplify the signals during the surgery.

Explanation

If the amplifier gets saturated during the exposure part of the surgery, resetting the amplifier can be a possible solution. By resetting the amplifier, it can help to resolve any technical issues or errors that may have caused the saturation. This can help to restore the amplifier to its normal functioning state and ensure that it is able to accurately amplify the signals during the surgery.

70. Evoked responses produced by unpatterned visual stimulation are known as:

Flash Visual Evoked Potentials (FVEP)

Electroretinograms (ERG)

Somatosensory Evoked Potentials (SSEP)

Brainstem Auditory Evoked Potentials (BAEP)

Flash Visual Evoked Potentials (FVEP) are evoked responses that are produced by unpatterned visual stimulation. This means that when a flash of light is presented to the visual system, it elicits a response that can be measured through electrodes placed on the scalp. FVEPs are commonly used in clinical settings to assess the function of the visual system, including the optic nerve and visual cortex. This technique allows for the evaluation of visual pathway integrity and can help diagnose conditions such as optic neuritis, multiple sclerosis, and other visual disorders.

Explanation

Flash Visual Evoked Potentials (FVEP) are evoked responses that are produced by unpatterned visual stimulation. This means that when a flash of light is presented to the visual system, it elicits a response that can be measured through electrodes placed on the scalp. FVEPs are commonly used in clinical settings to assess the function of the visual system, including the optic nerve and visual cortex. This technique allows for the evaluation of visual pathway integrity and can help diagnose conditions such as optic neuritis, multiple sclerosis, and other visual disorders.

71. Pattern Shift VEPs (PVEP) are affected by drowsiness.

True

False

Pattern Shift VEPs (PVEP) are affected by drowsiness. This means that when a person is feeling drowsy or sleepy, it can impact their Pattern Shift VEPs. This could result in changes or abnormalities in the brain's response to visual stimuli, leading to altered or impaired visual perception. Therefore, the statement "Pattern Shift VEPs (PVEP) are affected by drowsiness" is true.

Explanation

Pattern Shift VEPs (PVEP) are affected by drowsiness. This means that when a person is feeling drowsy or sleepy, it can impact their Pattern Shift VEPs. This could result in changes or abnormalities in the brain's response to visual stimuli, leading to altered or impaired visual perception. Therefore, the statement "Pattern Shift VEPs (PVEP) are affected by drowsiness" is true.

72. What body functions will be affected if the patient is diagnosed with apraxia?

Speech and motor

Sight and hearing

Taste and touch

Speech and sight

Apraxia is a neurological condition that affects a person's ability to perform purposeful movements, despite having the physical ability to do so. It primarily affects speech and motor functions. Speech apraxia causes difficulty in planning and coordinating the movements needed for speech production, resulting in problems with articulation and pronunciation. Motor apraxia, on the other hand, affects the ability to perform skilled movements, such as buttoning a shirt or using utensils. Therefore, if a patient is diagnosed with apraxia, their speech and motor functions will be affected.

Explanation

Apraxia is a neurological condition that affects a person's ability to perform purposeful movements, despite having the physical ability to do so. It primarily affects speech and motor functions. Speech apraxia causes difficulty in planning and coordinating the movements needed for speech production, resulting in problems with articulation and pronunciation. Motor apraxia, on the other hand, affects the ability to perform skilled movements, such as buttoning a shirt or using utensils. Therefore, if a patient is diagnosed with apraxia, their speech and motor functions will be affected.

73. The N18 subcortical response is a near field or far field response?

Far field

Near field

The N18 subcortical response is classified as a far field response. Far field responses refer to electrical activity generated by neural structures that are located at a distance from the recording electrodes. In the case of the N18 response, it is generated by subcortical structures such as the brainstem. This distinction is important because far field responses are less affected by artifacts and noise compared to near field responses, which originate from neural structures closer to the recording electrodes.

Explanation

The N18 subcortical response is classified as a far field response. Far field responses refer to electrical activity generated by neural structures that are located at a distance from the recording electrodes. In the case of the N18 response, it is generated by subcortical structures such as the brainstem. This distinction is important because far field responses are less affected by artifacts and noise compared to near field responses, which originate from neural structures closer to the recording electrodes.

74. Ohm's law is mathematically expressed as:

V=IR

I=RV

R=IV

V=I/R

Ohm's law states that the voltage across a conductor is directly proportional to the current flowing through it, with the constant of proportionality being the resistance of the conductor. This can be mathematically expressed as V=IR, where V is the voltage, I is the current, and R is the resistance. This equation shows that the voltage is equal to the product of the current and the resistance.

Explanation

Ohm's law states that the voltage across a conductor is directly proportional to the current flowing through it, with the constant of proportionality being the resistance of the conductor. This can be mathematically expressed as V=IR, where V is the voltage, I is the current, and R is the resistance. This equation shows that the voltage is equal to the product of the current and the resistance.

75. TIVA is an abbreviation for:

Total IntraVenous Anesthesia

Total IntraVenous Anesthetic

Total IntraVenomous Anesthesia

Type of IntraVenous Anesthesia

TIVA stands for Total IntraVenous Anesthesia, which refers to a method of administering anesthesia solely through intravenous means, without the use of inhaled anesthetics. This technique is commonly used in surgical procedures and provides a continuous and controlled level of anesthesia throughout the operation.

Explanation

TIVA stands for Total IntraVenous Anesthesia, which refers to a method of administering anesthesia solely through intravenous means, without the use of inhaled anesthetics. This technique is commonly used in surgical procedures and provides a continuous and controlled level of anesthesia throughout the operation.

76. Needle electrodes can be placed in this muscles in order to monitor cranial nerve V:

Masseter

Frontalis

Superior oblique

Inferior oblique

The masseter muscle is one of the main muscles responsible for the movement of the jaw. Cranial nerve V, also known as the trigeminal nerve, innervates the muscles of mastication, including the masseter muscle. Therefore, needle electrodes can be placed in the masseter muscle to monitor the activity of cranial nerve V.

Explanation

The masseter muscle is one of the main muscles responsible for the movement of the jaw. Cranial nerve V, also known as the trigeminal nerve, innervates the muscles of mastication, including the masseter muscle. Therefore, needle electrodes can be placed in the masseter muscle to monitor the activity of cranial nerve V.

77. What other modality should be included in addition to BAER for vestibular schwannoma surgery?

CN VII (Facial nerve) EMG

CN V (Trigeminal nerve) EMG

CN X (Vocal cord nerve) EMG

CN III (Oculomater nerve) EMG

CN VII (Facial nerve) EMG should be included in addition to BAER for vestibular schwannoma surgery because the facial nerve is at risk of injury during the procedure. Monitoring the facial nerve with EMG helps to identify any changes or damage to the nerve during surgery, allowing for immediate intervention and minimizing the risk of facial nerve dysfunction or paralysis. This modality helps the surgeon to ensure the preservation of facial nerve function and improve patient outcomes.

Explanation

CN VII (Facial nerve) EMG should be included in addition to BAER for vestibular schwannoma surgery because the facial nerve is at risk of injury during the procedure. Monitoring the facial nerve with EMG helps to identify any changes or damage to the nerve during surgery, allowing for immediate intervention and minimizing the risk of facial nerve dysfunction or paralysis. This modality helps the surgeon to ensure the preservation of facial nerve function and improve patient outcomes.

78. Which cranial nerve is sacrificed during the trans-labyrinthine approach surgery?

Vestibulocochlear nerve (CN VIII)

Olfactory nerve (CN I)

Trigeminal nerve (CN V)

Facial nerve (CN VII)

The trans-labyrinthine approach surgery involves sacrificing the Vestibulocochlear nerve (CN VIII). This nerve is responsible for transmitting auditory and balance information from the inner ear to the brain. Sacrificing this nerve is necessary in certain cases to access and remove tumors located in the inner ear or the cerebellopontine angle. By sacrificing CN VIII, the patient may experience permanent hearing loss and balance problems on the affected side.

Explanation

The trans-labyrinthine approach surgery involves sacrificing the Vestibulocochlear nerve (CN VIII). This nerve is responsible for transmitting auditory and balance information from the inner ear to the brain. Sacrificing this nerve is necessary in certain cases to access and remove tumors located in the inner ear or the cerebellopontine angle. By sacrificing CN VIII, the patient may experience permanent hearing loss and balance problems on the affected side.

79. One of the major risks of a wake up test is:

Accidental extubation

Patient memorization

Tongue laceration

Infections

Accidental extubation is one of the major risks of a wake-up test. This occurs when the endotracheal tube, which is used to maintain an open airway during surgery, is unintentionally removed. Accidental extubation can lead to serious complications, such as airway obstruction, aspiration of stomach contents, and decreased oxygenation. It is important to closely monitor the patient during a wake-up test to prevent this potential risk.

Explanation

Accidental extubation is one of the major risks of a wake-up test. This occurs when the endotracheal tube, which is used to maintain an open airway during surgery, is unintentionally removed. Accidental extubation can lead to serious complications, such as airway obstruction, aspiration of stomach contents, and decreased oxygenation. It is important to closely monitor the patient during a wake-up test to prevent this potential risk.

80. ERG may be absent with an inactive FVEP.

True

False

The statement suggests that ERG (Electroretinogram) can be absent even if there is an inactive FVEP (Flash Visual Evoked Potential). This means that the electrical activity in the retina may not be detected by the ERG test, even though the visual pathway to the brain is not functioning properly, as indicated by the inactive FVEP. Therefore, the statement is true.

Explanation

The statement suggests that ERG (Electroretinogram) can be absent even if there is an inactive FVEP (Flash Visual Evoked Potential). This means that the electrical activity in the retina may not be detected by the ERG test, even though the visual pathway to the brain is not functioning properly, as indicated by the inactive FVEP. Therefore, the statement is true.

81. The _ nerve should be stimulated __ to the side of cortical mapping.

Median & contralateral

Median & ipsilateral

Posterior tibial & contralateral

Posterior tibial & ipsilateral

During cortical mapping, the median nerve should be stimulated contralaterally. This means that the nerve on the opposite side of the brain from the area being mapped should be stimulated. Stimulation of the median nerve on the same side as the mapping could lead to inaccurate results.

Explanation

During cortical mapping, the median nerve should be stimulated contralaterally. This means that the nerve on the opposite side of the brain from the area being mapped should be stimulated. Stimulation of the median nerve on the same side as the mapping could lead to inaccurate results.

82. EMG train activity during surgical procedures involving the facial nerve can be caused by:

Nerve traction

Cold irrigation

Heating of the nerve

All of the above

EMG train activity refers to the electrical activity recorded from the facial nerve during surgical procedures. Nerve traction, cold irrigation, and heating of the nerve are all potential causes of this activity. Nerve traction occurs when the nerve is stretched or pulled during the procedure, leading to increased electrical activity. Cold irrigation involves the use of cold fluids during surgery, which can also stimulate the nerve and cause increased activity. Heating of the nerve can occur due to the use of electrosurgical devices or other sources of heat, leading to further electrical activity. Therefore, all of these factors can contribute to EMG train activity during surgical procedures involving the facial nerve.

Explanation

EMG train activity refers to the electrical activity recorded from the facial nerve during surgical procedures. Nerve traction, cold irrigation, and heating of the nerve are all potential causes of this activity. Nerve traction occurs when the nerve is stretched or pulled during the procedure, leading to increased electrical activity. Cold irrigation involves the use of cold fluids during surgery, which can also stimulate the nerve and cause increased activity. Heating of the nerve can occur due to the use of electrosurgical devices or other sources of heat, leading to further electrical activity. Therefore, all of these factors can contribute to EMG train activity during surgical procedures involving the facial nerve.

83. Damage to which nerve roots may result in foot drop?

L4-S1

S1-S2

L2-L4

L1-L3

Damage to the L4-S1 nerve roots may result in foot drop. The L4-S1 nerve roots are responsible for innervating the muscles that control dorsiflexion of the foot, which is necessary for lifting the foot and toes off the ground during walking. Damage to these nerve roots can lead to weakness or paralysis of the muscles involved in dorsiflexion, causing the foot to drag or drop when walking. This can significantly impair a person's ability to walk normally and may require assistive devices or rehabilitation to regain function.

Explanation

Damage to the L4-S1 nerve roots may result in foot drop. The L4-S1 nerve roots are responsible for innervating the muscles that control dorsiflexion of the foot, which is necessary for lifting the foot and toes off the ground during walking. Damage to these nerve roots can lead to weakness or paralysis of the muscles involved in dorsiflexion, causing the foot to drag or drop when walking. This can significantly impair a person's ability to walk normally and may require assistive devices or rehabilitation to regain function.

84. Sodium amytal is used for performing what type of testing?

Tinel's test

WADA test

Stagnara test

Babinski's test

Sodium amytal is used for performing the WADA test. The WADA test, also known as the intracarotid amobarbital procedure (IAP), is a medical test used to assess language and memory functions in the brain. During the test, sodium amytal is injected into the carotid artery to temporarily anesthetize one side of the brain. This allows the healthcare provider to evaluate the functions of the other side of the brain and determine the language and memory dominance.

Explanation

Sodium amytal is used for performing the WADA test. The WADA test, also known as the intracarotid amobarbital procedure (IAP), is a medical test used to assess language and memory functions in the brain. During the test, sodium amytal is injected into the carotid artery to temporarily anesthetize one side of the brain. This allows the healthcare provider to evaluate the functions of the other side of the brain and determine the language and memory dominance.

85. During left carotid endartectomy (CEA) surgery the cortical SSEP at risk will be for:

Right median nerve

Left median nerve

Left posterior tibial nerve

Right posterior tibial nerve

During left carotid endarterectomy (CEA) surgery, the cortical somatosensory evoked potential (SSEP) at risk will be for the right median nerve. This is because the left carotid endarterectomy involves the surgical removal of plaque from the left carotid artery, which can potentially affect the blood supply to the brain. SSEP monitoring is used during the surgery to assess the integrity of the sensory pathways in the brain. Since the right median nerve sends sensory signals to the brain, any disruption in blood supply during the surgery can lead to changes in the cortical SSEP specifically for the right median nerve.

Explanation

During left carotid endarterectomy (CEA) surgery, the cortical somatosensory evoked potential (SSEP) at risk will be for the right median nerve. This is because the left carotid endarterectomy involves the surgical removal of plaque from the left carotid artery, which can potentially affect the blood supply to the brain. SSEP monitoring is used during the surgery to assess the integrity of the sensory pathways in the brain. Since the right median nerve sends sensory signals to the brain, any disruption in blood supply during the surgery can lead to changes in the cortical SSEP specifically for the right median nerve.

86. The presence of delta activity in an infant below one year of age is normal or abnormal?

Normal

Abnormal

The presence of delta activity in an infant below one year of age is considered normal. Delta activity refers to slow brain waves that are typically seen during deep sleep. In infants, it is common for their sleep patterns to include a significant amount of deep sleep, which is characterized by delta activity. As the infant grows older, their sleep patterns will gradually change, and the amount of delta activity will decrease. Therefore, the presence of delta activity in an infant below one year of age is considered a normal part of their brain development.

Explanation

The presence of delta activity in an infant below one year of age is considered normal. Delta activity refers to slow brain waves that are typically seen during deep sleep. In infants, it is common for their sleep patterns to include a significant amount of deep sleep, which is characterized by delta activity. As the infant grows older, their sleep patterns will gradually change, and the amount of delta activity will decrease. Therefore, the presence of delta activity in an infant below one year of age is considered a normal part of their brain development.

87. A multi-pulse stimulation is optimal for activation of which structure to produce compound muscle action potentials (CMAP) in distal muscles?

Alpha motor neurons

Ion channels

Axons

Central sulcus

Multi-pulse stimulation is optimal for activation of alpha motor neurons to produce compound muscle action potentials (CMAP) in distal muscles. Alpha motor neurons are responsible for innervating skeletal muscles and are capable of generating action potentials that result in muscle contraction. By delivering multiple pulses of stimulation, it is possible to recruit a larger number of motor units and generate a stronger muscle contraction, leading to a larger CMAP response. Therefore, the activation of alpha motor neurons through multi-pulse stimulation is the most effective method for producing CMAP in distal muscles.

Explanation

Multi-pulse stimulation is optimal for activation of alpha motor neurons to produce compound muscle action potentials (CMAP) in distal muscles. Alpha motor neurons are responsible for innervating skeletal muscles and are capable of generating action potentials that result in muscle contraction. By delivering multiple pulses of stimulation, it is possible to recruit a larger number of motor units and generate a stronger muscle contraction, leading to a larger CMAP response. Therefore, the activation of alpha motor neurons through multi-pulse stimulation is the most effective method for producing CMAP in distal muscles.

88. The purpose of checking the electrode impedance for electrocorticography (EcoG) is:

To check the integrity of the electrodes

To make sure all necessary electrodes are the same metal

To check the leakage current of your machine

To check the amount of 60Hz noise in responses

Checking the electrode impedance for electrocorticography (ECoG) is done to assess the integrity of the electrodes. Impedance refers to the resistance to the flow of electrical current, and by measuring the impedance of the electrodes, it can be determined if they are functioning properly. This is important because any issues with the electrodes can affect the quality and accuracy of the ECoG recordings. Therefore, checking the integrity of the electrodes is a crucial step in ensuring the reliability of the ECoG data.

Explanation

Checking the electrode impedance for electrocorticography (ECoG) is done to assess the integrity of the electrodes. Impedance refers to the resistance to the flow of electrical current, and by measuring the impedance of the electrodes, it can be determined if they are functioning properly. This is important because any issues with the electrodes can affect the quality and accuracy of the ECoG recordings. Therefore, checking the integrity of the electrodes is a crucial step in ensuring the reliability of the ECoG data.

89. Ulnar nerve is formed by the spinal roots at which level?

C8-T1

C5-T1

C8-T3

C2-C5

The ulnar nerve is formed by the spinal roots at the C8-T1 level. This means that the nerve fibers from the eighth cervical (C8) and first thoracic (T1) spinal nerves come together to create the ulnar nerve.

Explanation

The ulnar nerve is formed by the spinal roots at the C8-T1 level. This means that the nerve fibers from the eighth cervical (C8) and first thoracic (T1) spinal nerves come together to create the ulnar nerve.

90. What is the blood supply of the spinal cord?

One anterior and two posterior arteries

Two anterior and one posterior arteries

One posterior artery

Two anterior arteries

The spinal cord is supplied with blood by one anterior and two posterior arteries. These arteries provide essential oxygen and nutrients to the spinal cord, ensuring its proper functioning. The anterior artery supplies blood to the front of the spinal cord, while the two posterior arteries supply blood to the back. This arrangement helps maintain a consistent blood flow and supports the overall health of the spinal cord.

Explanation

The spinal cord is supplied with blood by one anterior and two posterior arteries. These arteries provide essential oxygen and nutrients to the spinal cord, ensuring its proper functioning. The anterior artery supplies blood to the front of the spinal cord, while the two posterior arteries supply blood to the back. This arrangement helps maintain a consistent blood flow and supports the overall health of the spinal cord.

91. Which nerve should be stimulated for upper limb SSEP as recommended by ACNS guidelines for short latency SSEP?

Median nerve

Ulnar nerve

Posterior tibial nerve

Radial nerve

According to the ACNS guidelines for short latency SSEP, the recommended nerve to stimulate for upper limb SSEP is the median nerve.

Explanation

According to the ACNS guidelines for short latency SSEP, the recommended nerve to stimulate for upper limb SSEP is the median nerve.

92. If there is a sudden loss in ipsilateral ERB's point and contralateral N20 response, what is the first step for troubleshooting?

Check arm positioning

Check anesthesia

Check impedance

Wait for the response to return

The sudden loss in ipsilateral ERB's point and contralateral N20 response suggests a potential issue with the arm positioning. It is important to check if the patient's arm is properly positioned, as improper positioning can lead to nerve compression or stretching, resulting in a loss of response. By checking the arm positioning, any issues can be identified and corrected, potentially restoring the response.

Explanation

The sudden loss in ipsilateral ERB's point and contralateral N20 response suggests a potential issue with the arm positioning. It is important to check if the patient's arm is properly positioned, as improper positioning can lead to nerve compression or stretching, resulting in a loss of response. By checking the arm positioning, any issues can be identified and corrected, potentially restoring the response.

93. A very low current as small as 10mV that can be lethal to the patient if it passes through the heart is known as:

Microshock

Macroshock

Megashock

Minishock

A very low current as small as 10mV that can be lethal to the patient if it passes through the heart is known as microshock. This term is used to describe an electrical shock that occurs within the body, specifically affecting the heart. The small current may not be felt by the patient, but it can disrupt the normal electrical signals in the heart, potentially leading to cardiac arrest or other serious complications. Therefore, it is important to be aware of the potential dangers of microshock and take appropriate precautions to prevent it.

Explanation

A very low current as small as 10mV that can be lethal to the patient if it passes through the heart is known as microshock. This term is used to describe an electrical shock that occurs within the body, specifically affecting the heart. The small current may not be felt by the patient, but it can disrupt the normal electrical signals in the heart, potentially leading to cardiac arrest or other serious complications. Therefore, it is important to be aware of the potential dangers of microshock and take appropriate precautions to prevent it.

94. The electrical charge stored by a capacitor is known as:

Capacitance

Impedance

Inductance

Amperage

The electrical charge stored by a capacitor is known as capacitance. Capacitance is a measure of how much charge a capacitor can store per unit voltage. It is determined by the physical characteristics of the capacitor, such as the size of the plates and the distance between them. Impedance, inductance, and amperage are not related to the electrical charge stored by a capacitor.

Explanation

The electrical charge stored by a capacitor is known as capacitance. Capacitance is a measure of how much charge a capacitor can store per unit voltage. It is determined by the physical characteristics of the capacitor, such as the size of the plates and the distance between them. Impedance, inductance, and amperage are not related to the electrical charge stored by a capacitor.

95. What will be the disadvantage of synchornous stimulation?

Unable to identify a unilateral change

Stimulation to the patient's left and right sides separately

Unable to analyze pre-stimulus data

Unable to run SSEP and TcMEP congruently

The disadvantage of synchronous stimulation is that it is unable to identify a unilateral change. This means that if there is a change or abnormality occurring on one side of the patient's body, synchronous stimulation will not be able to detect it. This limitation can be problematic as it may lead to a failure in accurately diagnosing or monitoring certain conditions or abnormalities in the patient.

Explanation

The disadvantage of synchronous stimulation is that it is unable to identify a unilateral change. This means that if there is a change or abnormality occurring on one side of the patient's body, synchronous stimulation will not be able to detect it. This limitation can be problematic as it may lead to a failure in accurately diagnosing or monitoring certain conditions or abnormalities in the patient.

96. What is the normal resting membrane potential for a typical neuron?

-70mV

70mV

-70mA

70mA

The normal resting membrane potential for a typical neuron is -70mV. This means that the inside of the neuron is 70 millivolts more negative than the outside. This resting potential is maintained by the balance of ions inside and outside the neuron, with more sodium ions outside and more potassium ions inside. This potential is important for the proper functioning of the neuron and allows for the generation and transmission of electrical signals.

Explanation

The normal resting membrane potential for a typical neuron is -70mV. This means that the inside of the neuron is 70 millivolts more negative than the outside. This resting potential is maintained by the balance of ions inside and outside the neuron, with more sodium ions outside and more potassium ions inside. This potential is important for the proper functioning of the neuron and allows for the generation and transmission of electrical signals.

97. Most of the muscles of the eye are supplied by which cranial nerve?

CN III (Oculomotor)

CN II (Optic)

CN IV (Trochlear)

CN VI (Abducens)

The correct answer is CN III (Oculomotor). CN III is responsible for supplying most of the muscles of the eye. It controls the movement of the eyelid and the muscles that allow the eye to move up, down, and inward. CN II (Optic) is responsible for vision, CN IV (Trochlear) controls the superior oblique muscle, and CN VI (Abducens) controls the lateral rectus muscle. However, CN III is the main cranial nerve that supplies the majority of the eye muscles.

Explanation

The correct answer is CN III (Oculomotor). CN III is responsible for supplying most of the muscles of the eye. It controls the movement of the eyelid and the muscles that allow the eye to move up, down, and inward. CN II (Optic) is responsible for vision, CN IV (Trochlear) controls the superior oblique muscle, and CN VI (Abducens) controls the lateral rectus muscle. However, CN III is the main cranial nerve that supplies the majority of the eye muscles.

98. The responses recorded by an epidural electrode due to an indirect activation of corticospinal tract are known as:

I-Wave

D-Wave

SSEP

BAEP

The responses recorded by an epidural electrode due to an indirect activation of corticospinal tract are known as I-Wave.

Explanation

The responses recorded by an epidural electrode due to an indirect activation of corticospinal tract are known as I-Wave.

99. Good insulating materials that inhibit the current flow are:

Glass

Rubber

Wood

All of the above

Good insulating materials are those that prevent or inhibit the flow of electric current. Glass, rubber, and wood are all examples of materials that have high resistance and therefore act as insulators. These materials do not easily allow the movement of electrons, making them suitable for applications where electrical conductivity needs to be avoided. Therefore, the correct answer is "All of the above" as all three materials listed are good insulators.

Explanation

Good insulating materials are those that prevent or inhibit the flow of electric current. Glass, rubber, and wood are all examples of materials that have high resistance and therefore act as insulators. These materials do not easily allow the movement of electrons, making them suitable for applications where electrical conductivity needs to be avoided. Therefore, the correct answer is "All of the above" as all three materials listed are good insulators.

100. Impedance is defined as:

Opposition to an alternating current

Ability to store charge

Opposition to a direct current

Current that produces a magnetic field

Impedance is defined as the opposition to an alternating current. It refers to the total resistance, inductance, and capacitance in an electrical circuit. When an alternating current flows through a circuit, the impedance restricts its flow by resisting or impeding its passage. This opposition is caused by the combined effect of resistors, inductors, and capacitors in the circuit. Therefore, the correct answer is "Opposition to an alternating current."

Explanation

Impedance is defined as the opposition to an alternating current. It refers to the total resistance, inductance, and capacitance in an electrical circuit. When an alternating current flows through a circuit, the impedance restricts its flow by resisting or impeding its passage. This opposition is caused by the combined effect of resistors, inductors, and capacitors in the circuit. Therefore, the correct answer is "Opposition to an alternating current."

101. A negative N20 peak is generated in response to median nerve stimulation at:

Contralateral Somatosensory Cortex

Ipsilateral Somatosensory Cortex

Upper Brainstem/Thalamus

Caudal Medial Lemniscus

The correct answer is the Contralateral Somatosensory Cortex. When the median nerve is stimulated, it sends signals to the somatosensory cortex on the opposite side of the body. This leads to the generation of a negative N20 peak in the contralateral somatosensory cortex.

Explanation

The correct answer is the Contralateral Somatosensory Cortex. When the median nerve is stimulated, it sends signals to the somatosensory cortex on the opposite side of the body. This leads to the generation of a negative N20 peak in the contralateral somatosensory cortex.

102. A partial dislocation of a joint is known as:

Sublaxation

Spondylolisthesis

Spondylitis

Spina bifida

A partial dislocation of a joint is known as sublaxation. This term is used to describe a condition where the joint is not completely dislocated but is partially out of its normal position. Sublaxation can cause pain, instability, and limited range of motion in the affected joint. It is important to seek medical attention for sublaxation to prevent further damage and to receive appropriate treatment.

Explanation

A partial dislocation of a joint is known as sublaxation. This term is used to describe a condition where the joint is not completely dislocated but is partially out of its normal position. Sublaxation can cause pain, instability, and limited range of motion in the affected joint. It is important to seek medical attention for sublaxation to prevent further damage and to receive appropriate treatment.

103. What are other terms for stroke that might be found in the patient history, which are important to be aware of because your responses can be impacted?

Cerebrovascular accident (CVA)

Transient Ischemic Attack (TIA)

Both

Neither

Both terms, Cerebrovascular accident (CVA) and Transient Ischemic Attack (TIA), are other terms for stroke that might be found in the patient history. It is important to be aware of these terms because they indicate different types of strokes and can impact the appropriate response and treatment for the patient. A CVA refers to a more severe and permanent stroke, while a TIA is a temporary episode of stroke-like symptoms that resolve on their own. Understanding these terms helps healthcare professionals make informed decisions for the patient's care.

Explanation

Both terms, Cerebrovascular accident (CVA) and Transient Ischemic Attack (TIA), are other terms for stroke that might be found in the patient history. It is important to be aware of these terms because they indicate different types of strokes and can impact the appropriate response and treatment for the patient. A CVA refers to a more severe and permanent stroke, while a TIA is a temporary episode of stroke-like symptoms that resolve on their own. Understanding these terms helps healthcare professionals make informed decisions for the patient's care.

104. The active electrode is usually placed on the scalp 2cm behind _____ for lower limb SSEP.

Vertex (Cz)

Fpz

C3'

C4'

The active electrode is usually placed on the scalp 2cm behind the vertex (Cz) for lower limb SSEP. The vertex (Cz) is a specific location on the scalp that is commonly used as a reference point in electroencephalography (EEG) studies. Placing the electrode 2cm behind the vertex ensures accurate recording of the lower limb somatosensory evoked potentials (SSEP) by capturing the electrical activity from the relevant neural pathways. The other options, Fpz, C3', and C4', are not the recommended placement sites for lower limb SSEP.

Explanation

The active electrode is usually placed on the scalp 2cm behind the vertex (Cz) for lower limb SSEP. The vertex (Cz) is a specific location on the scalp that is commonly used as a reference point in electroencephalography (EEG) studies. Placing the electrode 2cm behind the vertex ensures accurate recording of the lower limb somatosensory evoked potentials (SSEP) by capturing the electrical activity from the relevant neural pathways. The other options, Fpz, C3', and C4', are not the recommended placement sites for lower limb SSEP.

105. Unequal electrode impedances may result in:

Increased noise

Current leakage

Normal responses

Chassis leakage

Unequal electrode impedances can result in increased noise because when the impedances of the electrodes are not balanced, it can lead to uneven electrical signals being picked up by the electrodes. This can introduce interference and noise into the signal being measured or recorded. The unequal impedances can cause variations in the voltage levels, resulting in a distorted and noisy signal. Therefore, it is important to have balanced electrode impedances to minimize noise and ensure accurate measurements.

Explanation

Unequal electrode impedances can result in increased noise because when the impedances of the electrodes are not balanced, it can lead to uneven electrical signals being picked up by the electrodes. This can introduce interference and noise into the signal being measured or recorded. The unequal impedances can cause variations in the voltage levels, resulting in a distorted and noisy signal. Therefore, it is important to have balanced electrode impedances to minimize noise and ensure accurate measurements.

106. What are the recommended bandpass filter settings for EEG recording?

1-70Hz

1-80mA

10-90Hz

1-17mA

The recommended bandpass filter settings for EEG recording are 1-70Hz. This range allows for the filtering of unwanted noise and artifacts while preserving the relevant frequency components of the EEG signal. Frequencies below 1Hz and above 70Hz are typically not of interest in EEG recordings and can be filtered out to improve signal quality.

Explanation

The recommended bandpass filter settings for EEG recording are 1-70Hz. This range allows for the filtering of unwanted noise and artifacts while preserving the relevant frequency components of the EEG signal. Frequencies below 1Hz and above 70Hz are typically not of interest in EEG recordings and can be filtered out to improve signal quality.

107. Median nerve is formed by the spinal roots at which level?

C5-T1

C8-T1

C8-T3

C2-C5

The correct answer is C5-T1. The median nerve is formed by the spinal roots at the level of C5-T1. These spinal roots originate from the brachial plexus, which is a network of nerves that innervates the upper limb. The median nerve provides motor and sensory innervation to the muscles and skin of the forearm and hand.

Explanation

The correct answer is C5-T1. The median nerve is formed by the spinal roots at the level of C5-T1. These spinal roots originate from the brachial plexus, which is a network of nerves that innervates the upper limb. The median nerve provides motor and sensory innervation to the muscles and skin of the forearm and hand.

108. Anal sphincter muscles are supplied by which nerve roots?

S2-S3-S4

S1-S2-S3

L5-S1-S2

L2-L3-L4

The anal sphincter muscles are supplied by the S2-S3-S4 nerve roots. These nerve roots are responsible for innervating the muscles that control the opening and closing of the anus. Dysfunction or damage to these nerve roots can result in issues with bowel control and continence.

Explanation

The anal sphincter muscles are supplied by the S2-S3-S4 nerve roots. These nerve roots are responsible for innervating the muscles that control the opening and closing of the anus. Dysfunction or damage to these nerve roots can result in issues with bowel control and continence.

109. If the anterior cerebral artery is occluded, PTN SSEP responses will be affected.

True

False

If the anterior cerebral artery is occluded, it can lead to a decrease in blood supply to the brain, specifically the areas supplied by this artery. This can result in impairment or loss of function in the corresponding brain regions. PTN SSEP (Posterior Tibial Nerve Somatosensory Evoked Potential) responses are used to assess the integrity of the sensory pathways in the brain. Since the occlusion of the anterior cerebral artery affects blood supply to the brain, it can disrupt the normal functioning of the sensory pathways and thus affect the PTN SSEP responses. Therefore, the statement is true.

Explanation

If the anterior cerebral artery is occluded, it can lead to a decrease in blood supply to the brain, specifically the areas supplied by this artery. This can result in impairment or loss of function in the corresponding brain regions. PTN SSEP (Posterior Tibial Nerve Somatosensory Evoked Potential) responses are used to assess the integrity of the sensory pathways in the brain. Since the occlusion of the anterior cerebral artery affects blood supply to the brain, it can disrupt the normal functioning of the sensory pathways and thus affect the PTN SSEP responses. Therefore, the statement is true.

110. If you feel a shock from the IOM equipment what is the first step to do?

Disconnect the patient from IOM equipment

Inform the surgeon

Inform the circulation nurse and the surgeon

Stop all stimulation to the patient

If a person feels a shock from the IOM (Intraoperative Monitoring) equipment, the first step they should take is to disconnect themselves from the equipment. This is important to ensure their safety and prevent further harm. Informing the surgeon and circulation nurse about the incident should also be done, but the immediate action of disconnecting is crucial to prevent any further harm or injury. Additionally, stopping all stimulation to the patient may be necessary, but it is not the first step to take in this situation.

Explanation

If a person feels a shock from the IOM (Intraoperative Monitoring) equipment, the first step they should take is to disconnect themselves from the equipment. This is important to ensure their safety and prevent further harm. Informing the surgeon and circulation nurse about the incident should also be done, but the immediate action of disconnecting is crucial to prevent any further harm or injury. Additionally, stopping all stimulation to the patient may be necessary, but it is not the first step to take in this situation.

111. When is the best time to set baselines?

Postinduction and preincision

Preinduction

Postincision

Postincision and predecompression

The best time to set baselines is after the patient has been induced with anesthesia and before the incision is made. This allows for accurate measurements and comparisons to be made before any surgical manipulation or intervention occurs. By setting baselines at this specific time, healthcare professionals can establish a starting point for monitoring the patient's vital signs and other parameters throughout the surgical procedure.

Explanation

The best time to set baselines is after the patient has been induced with anesthesia and before the incision is made. This allows for accurate measurements and comparisons to be made before any surgical manipulation or intervention occurs. By setting baselines at this specific time, healthcare professionals can establish a starting point for monitoring the patient's vital signs and other parameters throughout the surgical procedure.

112. Dilantin is used for treating:

Seizures

Pain

Allergies

Stimulant

Dilantin is a medication commonly used for treating seizures. It belongs to a class of drugs called anticonvulsants, which work by stabilizing electrical activity in the brain to prevent seizures. Dilantin is often prescribed for various types of seizures, including generalized tonic-clonic seizures, complex partial seizures, and seizures caused by epilepsy or brain injury. It is not used for treating pain, allergies, or as a stimulant.

Explanation

Dilantin is a medication commonly used for treating seizures. It belongs to a class of drugs called anticonvulsants, which work by stabilizing electrical activity in the brain to prevent seizures. Dilantin is often prescribed for various types of seizures, including generalized tonic-clonic seizures, complex partial seizures, and seizures caused by epilepsy or brain injury. It is not used for treating pain, allergies, or as a stimulant.

113. I-Wave responses are very sensitive to anesthetic agents.

True

False

I-Wave responses are very sensitive to anesthetic agents, meaning that the electrical activity in the brain, known as I-Wave responses, can be significantly affected by the presence of anesthetics. This sensitivity suggests that anesthetics can have a strong impact on the brain's electrical signals and potentially alter brain function during anesthesia.

Explanation

I-Wave responses are very sensitive to anesthetic agents, meaning that the electrical activity in the brain, known as I-Wave responses, can be significantly affected by the presence of anesthetics. This sensitivity suggests that anesthetics can have a strong impact on the brain's electrical signals and potentially alter brain function during anesthesia.

114. MEPs are known as cathodal or anodal stimulation?

Anodal stimulation

Cathodal stimulation

Anodal stimulation refers to the process of applying a positive electric charge to an electrode, which results in the depolarization of neurons and an increase in their excitability. This type of stimulation is commonly used in transcranial direct current stimulation (tDCS) to enhance cognitive functions or treat certain neurological disorders. In contrast, cathodal stimulation involves the application of a negative charge to an electrode, leading to hyperpolarization and a decrease in neuronal excitability. Therefore, MEPs (motor evoked potentials) are known as anodal stimulation rather than cathodal stimulation.

Explanation

Anodal stimulation refers to the process of applying a positive electric charge to an electrode, which results in the depolarization of neurons and an increase in their excitability. This type of stimulation is commonly used in transcranial direct current stimulation (tDCS) to enhance cognitive functions or treat certain neurological disorders. In contrast, cathodal stimulation involves the application of a negative charge to an electrode, leading to hyperpolarization and a decrease in neuronal excitability. Therefore, MEPs (motor evoked potentials) are known as anodal stimulation rather than cathodal stimulation.

115. The tapered, lower end of the spinal cord is called:

Conus Medullaris

Lumbosacral Plexus

Filum Terminale

S4

The tapered, lower end of the spinal cord is called the conus medullaris. This is the terminal portion of the spinal cord, located at the level of the first or second lumbar vertebra. It marks the end of the spinal cord proper and gives rise to the cauda equina, a bundle of nerves that continues down the vertebral canal. The conus medullaris is an important anatomical landmark in the spinal cord and is involved in the transmission of sensory and motor information.

Explanation

The tapered, lower end of the spinal cord is called the conus medullaris. This is the terminal portion of the spinal cord, located at the level of the first or second lumbar vertebra. It marks the end of the spinal cord proper and gives rise to the cauda equina, a bundle of nerves that continues down the vertebral canal. The conus medullaris is an important anatomical landmark in the spinal cord and is involved in the transmission of sensory and motor information.

116. The cerebral cortex is mapped by:

Placing a cortical grid across the central sulcus

Placing a cortical grid lateral on the central sulcus

Placing a cortical grid across the sensory cortex

Placing a cortical grid across the motor cortex

The correct answer is placing a cortical grid across the central sulcus. The central sulcus is a prominent fold in the cerebral cortex that separates the frontal lobe from the parietal lobe. By placing a cortical grid across the central sulcus, researchers can map and study the different regions of the cerebral cortex, including the sensory and motor cortex. This allows them to understand the functions and organization of the brain in relation to different areas of the cortex.

Explanation

The correct answer is placing a cortical grid across the central sulcus. The central sulcus is a prominent fold in the cerebral cortex that separates the frontal lobe from the parietal lobe. By placing a cortical grid across the central sulcus, researchers can map and study the different regions of the cerebral cortex, including the sensory and motor cortex. This allows them to understand the functions and organization of the brain in relation to different areas of the cortex.

117. A large current passing form an external surface to another is known as:

Macroshock

Microshock

Megashock

Minishock

not-available-via-ai

Explanation

not-available-via-ai

118. Electrocochleogram (ECochG) consists of combinations of which responses?

Cochlear Microphonic (CM), Summating Potentials (SP), and auditory nerve compound action potentials

Somatosensory Evoked Potentials (SSEP) and Summating Potentials (SP)

Somatosensory Evoked Potentials (SSEP) and Motor Evoked Potentials (TcMEP)

Summating Potentials (SP) and auditory nerve compound action potentials

The correct answer is Cochlear Microphonic (CM), Summating Potentials (SP), and auditory nerve compound action potentials. These are the combinations of responses that make up the Electrocochleogram (ECochG). The CM is a low-frequency response generated by the outer hair cells in the cochlea, the SP is a mid-frequency response generated by the inner hair cells and auditory nerve fibers, and the auditory nerve compound action potentials are high-frequency responses generated by the auditory nerve fibers. Together, these responses provide valuable information about the function of the cochlea and auditory nerve.

Explanation

The correct answer is Cochlear Microphonic (CM), Summating Potentials (SP), and auditory nerve compound action potentials. These are the combinations of responses that make up the Electrocochleogram (ECochG). The CM is a low-frequency response generated by the outer hair cells in the cochlea, the SP is a mid-frequency response generated by the inner hair cells and auditory nerve fibers, and the auditory nerve compound action potentials are high-frequency responses generated by the auditory nerve fibers. Together, these responses provide valuable information about the function of the cochlea and auditory nerve.

119. Minimum Common Mode Rejection Ratio (CMRR) of a differential amplifier should be:

10,000:1 or 80db

1,000:1 or 60db

100,000:1 or 100db

1,000,000:1, 120db

The minimum Common Mode Rejection Ratio (CMRR) of a differential amplifier should be 10,000:1 or 80db. CMRR is a measure of how well a differential amplifier rejects common mode signals, which are signals that appear equally on both inputs. A higher CMRR indicates better rejection of these common mode signals. Therefore, a minimum CMRR of 10,000:1 or 80db ensures that the differential amplifier can effectively reject common mode noise and interference.

Explanation

The minimum Common Mode Rejection Ratio (CMRR) of a differential amplifier should be 10,000:1 or 80db. CMRR is a measure of how well a differential amplifier rejects common mode signals, which are signals that appear equally on both inputs. A higher CMRR indicates better rejection of these common mode signals. Therefore, a minimum CMRR of 10,000:1 or 80db ensures that the differential amplifier can effectively reject common mode noise and interference.

120. The vertical resolution of an IOM machine depends upon:

Size of analog to digital convertor (ADC)

The patient

The input impedance of the machine

The signal to noise ratio (SNR)

The vertical resolution of an IOM machine depends on the size of the analog to digital converter (ADC). The ADC is responsible for converting the analog signals from the patient into digital signals that can be processed by the machine. The size of the ADC determines the number of bits used to represent the digital signal, which in turn affects the resolution of the signal. A larger ADC size allows for more precise and detailed representation of the analog signal, resulting in a higher vertical resolution.

Explanation

The vertical resolution of an IOM machine depends on the size of the analog to digital converter (ADC). The ADC is responsible for converting the analog signals from the patient into digital signals that can be processed by the machine. The size of the ADC determines the number of bits used to represent the digital signal, which in turn affects the resolution of the signal. A larger ADC size allows for more precise and detailed representation of the analog signal, resulting in a higher vertical resolution.

121. The generator of Wave I of the BAEP response is:

Distal Auditory Nerve

Proximal Auditory Nerve

Cochlear Nucleus

Inferior Colliculus

The generator of Wave I of the BAEP response is the Distal Auditory Nerve. This is because Wave I represents the initial auditory nerve response to sound stimuli. The Distal Auditory Nerve is responsible for transmitting auditory information from the cochlea to the brainstem.

Explanation

The generator of Wave I of the BAEP response is the Distal Auditory Nerve. This is because Wave I represents the initial auditory nerve response to sound stimuli. The Distal Auditory Nerve is responsible for transmitting auditory information from the cochlea to the brainstem.

122. Bipolar stimulation of the exposed motor cortex using bipolar probe with 50-60Hz stimulation is known as:

Penfield’s technique

Romberg's technique

Babinski's technique

Hoffman's technique

Penfield's technique refers to the use of bipolar stimulation of the exposed motor cortex using a bipolar probe with 50-60Hz stimulation. This technique is named after Wilder Penfield, a Canadian neurosurgeon who developed it in the 1930s. It involves applying small electrical currents to specific areas of the motor cortex to map out the functional areas of the brain and identify the motor representation of different body parts. This technique has been widely used in neurosurgery to guide the removal of brain tumors and to identify and preserve critical motor functions.

Explanation

Penfield's technique refers to the use of bipolar stimulation of the exposed motor cortex using a bipolar probe with 50-60Hz stimulation. This technique is named after Wilder Penfield, a Canadian neurosurgeon who developed it in the 1930s. It involves applying small electrical currents to specific areas of the motor cortex to map out the functional areas of the brain and identify the motor representation of different body parts. This technique has been widely used in neurosurgery to guide the removal of brain tumors and to identify and preserve critical motor functions.

123. What is the location of injury if there is loss of subcortical and cortical SSEP responses but intact ERB's point response?

Brainstem / Thalamus

Brachial Plexus

Motor Cortex

Somatosensory Cortex

Loss of subcortical and cortical SSEP responses but intact ERB's point response suggests an injury in the brainstem or thalamus. SSEP responses originate from the sensory pathways in the brain, including the subcortical and cortical regions. If these responses are lost, it indicates a disruption in these areas. On the other hand, ERB's point response is a test for the integrity of the brachial plexus, which is a network of nerves in the shoulder and arm. If this response is intact, it suggests that the injury is not in the brachial plexus. Therefore, the most likely location of the injury is in the brainstem or thalamus.

Explanation

Loss of subcortical and cortical SSEP responses but intact ERB's point response suggests an injury in the brainstem or thalamus. SSEP responses originate from the sensory pathways in the brain, including the subcortical and cortical regions. If these responses are lost, it indicates a disruption in these areas. On the other hand, ERB's point response is a test for the integrity of the brachial plexus, which is a network of nerves in the shoulder and arm. If this response is intact, it suggests that the injury is not in the brachial plexus. Therefore, the most likely location of the injury is in the brainstem or thalamus.

124. What is the maximum allowable chassis leakage current?

Less than 300uA RMS with ground open

Less than 400uA RMS with ground open

Less than 350uA RMS with ground open

Less than 325uA RMS with ground open

The maximum allowable chassis leakage current is less than 300uA RMS with ground open. This means that the amount of current that can leak from the chassis of the device to the ground when it is open should be less than 300uA RMS. This is an important specification to ensure the safety and proper functioning of the device.

Explanation

The maximum allowable chassis leakage current is less than 300uA RMS with ground open. This means that the amount of current that can leak from the chassis of the device to the ground when it is open should be less than 300uA RMS. This is an important specification to ensure the safety and proper functioning of the device.

125. The cortical grid is made of what type of metal?

Platinum

Gold

Silver

Nickel

The cortical grid is made of platinum.

Explanation

The cortical grid is made of platinum.

126. Intracranial stimulation of the facial nerve (CN VII) produces a muscle response at a latency of approximately:

7ms

5ms

3ms

9ms

Intracranial stimulation of the facial nerve (CN VII) produces a muscle response at a latency of approximately 7ms. Latency refers to the time it takes for a response to occur after a stimulus is applied. In this case, when the facial nerve is stimulated within the brain, it takes approximately 7ms for the muscle response to occur.

Explanation

Intracranial stimulation of the facial nerve (CN VII) produces a muscle response at a latency of approximately 7ms. Latency refers to the time it takes for a response to occur after a stimulus is applied. In this case, when the facial nerve is stimulated within the brain, it takes approximately 7ms for the muscle response to occur.

127. The monopolar electrode for pedicle screw stimulation should be plugged into a cathode or anode?

Cathode

Anode

The monopolar electrode for pedicle screw stimulation should be plugged into the cathode because the cathode is the negatively charged electrode. When the cathode is connected to the monopolar electrode, it allows for the flow of electrons from the electrode to the surrounding tissue. This flow of electrons stimulates the nerves and muscles in the area, providing therapeutic benefits. Plugging the electrode into the anode, which is the positively charged electrode, would result in the opposite effect and may not produce the desired stimulation.

Explanation

The monopolar electrode for pedicle screw stimulation should be plugged into the cathode because the cathode is the negatively charged electrode. When the cathode is connected to the monopolar electrode, it allows for the flow of electrons from the electrode to the surrounding tissue. This flow of electrons stimulates the nerves and muscles in the area, providing therapeutic benefits. Plugging the electrode into the anode, which is the positively charged electrode, would result in the opposite effect and may not produce the desired stimulation.

128. Femoral nerve is formed by the spinal roots at which level?

L2-L4

L4-S3

S2-S4

L3-S4

The femoral nerve is formed by the spinal roots at the level of L2-L4. This means that the nerve is derived from the second, third, and fourth lumbar vertebrae in the spinal column. These spinal roots come together to form the femoral nerve, which is responsible for providing sensation to the front of the thigh and inner leg, as well as controlling the muscles that extend the leg at the knee joint.

Explanation

The femoral nerve is formed by the spinal roots at the level of L2-L4. This means that the nerve is derived from the second, third, and fourth lumbar vertebrae in the spinal column. These spinal roots come together to form the femoral nerve, which is responsible for providing sensation to the front of the thigh and inner leg, as well as controlling the muscles that extend the leg at the knee joint.

129. Opposition to change in current flow is known as:

Inductance

Amperage

Capacitance

60Hz noise

Inductance refers to the opposition or resistance to a change in current flow in a circuit. It is caused by the presence of an inductor, which stores energy in the form of a magnetic field. When the current flowing through the inductor changes, the magnetic field also changes, creating a counter electromotive force that opposes the change in current. Therefore, inductance can be considered as the opposition to change in current flow.

Explanation

Inductance refers to the opposition or resistance to a change in current flow in a circuit. It is caused by the presence of an inductor, which stores energy in the form of a magnetic field. When the current flowing through the inductor changes, the magnetic field also changes, creating a counter electromotive force that opposes the change in current. Therefore, inductance can be considered as the opposition to change in current flow.

130. The impedances of subdermal needle electrodes are typically higher than scalp electrodes.

True

False

Subdermal needle electrodes are inserted beneath the skin, while scalp electrodes are placed on the surface of the scalp. The impedance of an electrode refers to its resistance to the flow of electrical current. Since subdermal needle electrodes are inserted deeper into the tissue, they encounter more resistance compared to scalp electrodes, which are closer to the surface. Therefore, the statement that the impedances of subdermal needle electrodes are typically higher than scalp electrodes is true.

Explanation

Subdermal needle electrodes are inserted beneath the skin, while scalp electrodes are placed on the surface of the scalp. The impedance of an electrode refers to its resistance to the flow of electrical current. Since subdermal needle electrodes are inserted deeper into the tissue, they encounter more resistance compared to scalp electrodes, which are closer to the surface. Therefore, the statement that the impedances of subdermal needle electrodes are typically higher than scalp electrodes is true.

131. Needle electrodes can be placed in this muscle in order to monitor cranial nerve XI:

Trapezius

Tongue

Soft palate glossopharyngeal

Vocal cords

Needle electrodes can be placed in the trapezius muscle in order to monitor cranial nerve XI. The trapezius muscle is innervated by cranial nerve XI, also known as the accessory nerve, which controls the movement of the shoulder and neck. By placing needle electrodes in the trapezius muscle, the activity of cranial nerve XI can be monitored and assessed. This can be useful in diagnosing and evaluating conditions that affect the function of this nerve, such as nerve damage or muscle weakness.

Explanation

Needle electrodes can be placed in the trapezius muscle in order to monitor cranial nerve XI. The trapezius muscle is innervated by cranial nerve XI, also known as the accessory nerve, which controls the movement of the shoulder and neck. By placing needle electrodes in the trapezius muscle, the activity of cranial nerve XI can be monitored and assessed. This can be useful in diagnosing and evaluating conditions that affect the function of this nerve, such as nerve damage or muscle weakness.

132. The summation of positive and negative charges by which cortical cells produce EEG are generated by what type of neuron?

Pyramidal cells

Surface cells

Epidural cells

Glial cells

Pyramidal cells are the main type of neurons found in the cerebral cortex, and they play a crucial role in generating the electrical activity measured by EEG. These cells have a pyramidal shape and are responsible for transmitting signals from one area of the cortex to another. They are known to generate both positive and negative charges, which contribute to the summation of electrical activity observed in EEG recordings. Therefore, pyramidal cells are the correct answer for the question.

Explanation

Pyramidal cells are the main type of neurons found in the cerebral cortex, and they play a crucial role in generating the electrical activity measured by EEG. These cells have a pyramidal shape and are responsible for transmitting signals from one area of the cortex to another. They are known to generate both positive and negative charges, which contribute to the summation of electrical activity observed in EEG recordings. Therefore, pyramidal cells are the correct answer for the question.

133. The best muscle used for recording lower limb TcMEP is:

Abductor hallucis brevis (AHB)

Tibialis anterior (TA)

Tibialis posterior (TP)

Flexor digitorum longus (FDL)

The abductor hallucis brevis (AHB) muscle is the best muscle used for recording lower limb TcMEP (Transcranial Motor Evoked Potentials) because it is located in the foot and is innervated by the tibial nerve. This muscle is responsible for the abduction of the big toe, making it an ideal choice for assessing the function of the lower limb during TcMEP recordings.

Explanation

The abductor hallucis brevis (AHB) muscle is the best muscle used for recording lower limb TcMEP (Transcranial Motor Evoked Potentials) because it is located in the foot and is innervated by the tibial nerve. This muscle is responsible for the abduction of the big toe, making it an ideal choice for assessing the function of the lower limb during TcMEP recordings.

134. D-Wave responses are very sensitive to anesthetic agents.

False

True

D-Wave responses are not sensitive to anesthetic agents.

Explanation

D-Wave responses are not sensitive to anesthetic agents.

135. The purpose of IOM during tethered cord surgeries is:

Identification and resection of filum terminale

Protection of the posterior spinal cord arteries

Creation of data regarding the status of motor function

None of the above

The purpose of IOM (Intraoperative Monitoring) during tethered cord surgeries is the identification and resection of filum terminale. This refers to the surgical procedure where the filum terminale, a thin thread-like structure at the end of the spinal cord, is identified and removed to relieve tension and improve symptoms associated with tethered cord syndrome. IOM helps in monitoring the neural pathways and spinal cord function during the surgery to ensure the safety and efficacy of the procedure.

Explanation

The purpose of IOM (Intraoperative Monitoring) during tethered cord surgeries is the identification and resection of filum terminale. This refers to the surgical procedure where the filum terminale, a thin thread-like structure at the end of the spinal cord, is identified and removed to relieve tension and improve symptoms associated with tethered cord syndrome. IOM helps in monitoring the neural pathways and spinal cord function during the surgery to ensure the safety and efficacy of the procedure.

136. P300 is what type of an evoked response?

Event related potentials (ERP)

Somatosensory evoked potential (SSEP)

Brainstem auditory evoked potentials (BAEP)

Triggered electromyography potential (TEP)

The correct answer is Event related potentials (ERP). P300 is a type of event related potential that is measured using electroencephalography (EEG). It is a positive wave that occurs approximately 300 milliseconds after a stimulus is presented. P300 is associated with cognitive processes such as attention, memory, and decision-making. It is often used in research and clinical settings to study cognitive function and to diagnose neurological disorders.

Explanation

The correct answer is Event related potentials (ERP). P300 is a type of event related potential that is measured using electroencephalography (EEG). It is a positive wave that occurs approximately 300 milliseconds after a stimulus is presented. P300 is associated with cognitive processes such as attention, memory, and decision-making. It is often used in research and clinical settings to study cognitive function and to diagnose neurological disorders.

137. How can we avoid electrode polarization in the OR?

Use of electrode with the same identical metal

Plug in a ground electrode

Use of surface pads instead of subdermal needles

Reset the amplifier

To avoid electrode polarization in the operating room, it is recommended to use electrodes with the same identical metal. This is because when different metals are used, an electrochemical reaction can occur at the interface between the metal and the electrolyte, leading to polarization. By using electrodes with the same metal, the likelihood of this reaction is minimized, ensuring accurate and reliable measurements.

Explanation

To avoid electrode polarization in the operating room, it is recommended to use electrodes with the same identical metal. This is because when different metals are used, an electrochemical reaction can occur at the interface between the metal and the electrolyte, leading to polarization. By using electrodes with the same metal, the likelihood of this reaction is minimized, ensuring accurate and reliable measurements.

138. Pudendal nerve is formed by the spinal roots at which level?

S2-S4

L2-L4

L3-S4

L4-S3

The pudendal nerve is formed by the spinal roots at the S2-S4 level. This is because the pudendal nerve originates from the sacral plexus, which is formed by the spinal roots of the sacral segments S2-S4. These spinal roots combine to form the pudendal nerve, which supplies sensory and motor innervation to the perineum, external genitalia, and anal region.

Explanation

The pudendal nerve is formed by the spinal roots at the S2-S4 level. This is because the pudendal nerve originates from the sacral plexus, which is formed by the spinal roots of the sacral segments S2-S4. These spinal roots combine to form the pudendal nerve, which supplies sensory and motor innervation to the perineum, external genitalia, and anal region.

139. The ability to speak after electrical stimulation of the Broca's area is known as?

Aphasia

Tinnitus

Ataxia

Apraxia

Aphasia is the correct answer because it is a condition characterized by the loss or impairment of the ability to speak or understand language. Electrical stimulation of the Broca's area, which is responsible for language production, can sometimes restore speech abilities in individuals with aphasia. Tinnitus is a condition characterized by ringing in the ears, ataxia is a lack of muscle coordination, and apraxia is a motor disorder affecting the ability to perform voluntary movements.

Explanation

Aphasia is the correct answer because it is a condition characterized by the loss or impairment of the ability to speak or understand language. Electrical stimulation of the Broca's area, which is responsible for language production, can sometimes restore speech abilities in individuals with aphasia. Tinnitus is a condition characterized by ringing in the ears, ataxia is a lack of muscle coordination, and apraxia is a motor disorder affecting the ability to perform voluntary movements.

140. The N34 subcortical response is a near field or far field response?

Near field

Far field

The N34 subcortical response is categorized as a far field response. Far field responses refer to electrical activity that originates from a distant source and can be recorded at a separate location. In the case of the N34 subcortical response, it is an electrical signal that is generated in the brain and can be measured at a location away from the source. This categorization helps in understanding the nature and characteristics of the response in terms of its generation and recording.

Explanation

The N34 subcortical response is categorized as a far field response. Far field responses refer to electrical activity that originates from a distant source and can be recorded at a separate location. In the case of the N34 subcortical response, it is an electrical signal that is generated in the brain and can be measured at a location away from the source. This categorization helps in understanding the nature and characteristics of the response in terms of its generation and recording.

141. If an injection of Pavulon is given to the patient during surgery, it will affect:

EMG and TcMEP

SSEP

EEG

BAER

When an injection of Pavulon is given to a patient during surgery, it will affect EMG (electromyography) and TcMEP (transcranial motor evoked potentials). Pavulon is a neuromuscular blocking agent that causes temporary paralysis by blocking the transmission of nerve signals to the muscles. This will result in a decrease or absence of muscle activity, which can be detected by EMG. TcMEP measures the electrical activity of the muscles in response to stimulation of the motor cortex, and since Pavulon affects the transmission of nerve signals, it will also affect TcMEP.

Explanation

When an injection of Pavulon is given to a patient during surgery, it will affect EMG (electromyography) and TcMEP (transcranial motor evoked potentials). Pavulon is a neuromuscular blocking agent that causes temporary paralysis by blocking the transmission of nerve signals to the muscles. This will result in a decrease or absence of muscle activity, which can be detected by EMG. TcMEP measures the electrical activity of the muscles in response to stimulation of the motor cortex, and since Pavulon affects the transmission of nerve signals, it will also affect TcMEP.

142. Needle electrodes can be placed in this muscles in order to monitor cranial nerve XII:

Tongue

Trapezius

Soft palate glossopharyngeal

Vocal cords

Needle electrodes can be placed in the tongue muscles to monitor the activity of cranial nerve XII, also known as the hypoglossal nerve. This nerve controls the movement of the tongue, and by monitoring the electrical signals in the tongue muscles, the function of cranial nerve XII can be assessed.

Explanation

Needle electrodes can be placed in the tongue muscles to monitor the activity of cranial nerve XII, also known as the hypoglossal nerve. This nerve controls the movement of the tongue, and by monitoring the electrical signals in the tongue muscles, the function of cranial nerve XII can be assessed.

143. Luque instrumentation consists of:

Two flexible L-Shaped rods and sublaminar wires

Rods and hooks

Wires and rods

Screws and caps

Luque instrumentation consists of two flexible L-Shaped rods and sublaminar wires. This type of instrumentation is commonly used in spinal surgeries, particularly for scoliosis correction. The rods are shaped like an "L" and are flexible to allow for better contouring to the spine. The sublaminar wires are placed under the lamina of the vertebrae and are used to provide additional stability and support. This combination of rods and wires helps to correct the curvature of the spine and maintain proper alignment.

Explanation

Luque instrumentation consists of two flexible L-Shaped rods and sublaminar wires. This type of instrumentation is commonly used in spinal surgeries, particularly for scoliosis correction. The rods are shaped like an "L" and are flexible to allow for better contouring to the spine. The sublaminar wires are placed under the lamina of the vertebrae and are used to provide additional stability and support. This combination of rods and wires helps to correct the curvature of the spine and maintain proper alignment.

144. The main components of Flash ERG are:

A-Wave and B-Wave

D-Wave and I-Wave

Obligate peaks

Waves I, III, and V

The main components of Flash ERG are the A-Wave and B-Wave. The A-Wave represents the initial negative deflection of the ERG response, while the B-Wave represents the subsequent positive deflection. These waves are important in evaluating the function of the retina and can provide information about the health and integrity of the photoreceptor cells.

Explanation

The main components of Flash ERG are the A-Wave and B-Wave. The A-Wave represents the initial negative deflection of the ERG response, while the B-Wave represents the subsequent positive deflection. These waves are important in evaluating the function of the retina and can provide information about the health and integrity of the photoreceptor cells.

145. Posterior Tibial nerve is formed by the spinal roots at which level?

L4-S3

S2-S4

L3-S4

L2-L4

The posterior tibial nerve is formed by the spinal roots at the level of L4-S3. This means that the nerve is derived from the spinal nerves that exit the spinal cord between the fourth lumbar vertebra and the third sacral vertebra. These spinal roots come together to form the posterior tibial nerve, which supplies sensation and motor function to the posterior compartment of the leg and the sole of the foot.

Explanation

The posterior tibial nerve is formed by the spinal roots at the level of L4-S3. This means that the nerve is derived from the spinal nerves that exit the spinal cord between the fourth lumbar vertebra and the third sacral vertebra. These spinal roots come together to form the posterior tibial nerve, which supplies sensation and motor function to the posterior compartment of the leg and the sole of the foot.

146. The most reliable criteria for SSEP abnormality is:

Absence of the obligate waveforms

Prolongation of the inter-peak latencies

Both

Neither

The most reliable criteria for SSEP abnormality is the presence of both absence of the obligate waveforms and prolongation of the inter-peak latencies. This means that if either of these criteria is present, it indicates an abnormality in the SSEP.

Explanation

The most reliable criteria for SSEP abnormality is the presence of both absence of the obligate waveforms and prolongation of the inter-peak latencies. This means that if either of these criteria is present, it indicates an abnormality in the SSEP.

147. Intraoperative TCD is most commonly used during which surgery?

Carotid Endartectomy

Facial Nerve Decompression

CPA Tumor

Anterior Cervical Decompression & Fusion

Intraoperative TCD, which stands for Transcranial Doppler, is commonly used during Carotid Endartectomy surgery. This procedure involves removing plaque buildup from the carotid artery in order to improve blood flow to the brain. Intraoperative TCD is used during this surgery to monitor blood flow and detect any potential complications such as emboli or changes in cerebral blood flow. By using TCD, surgeons can ensure that the procedure is being performed successfully and that there are no adverse effects on the brain's blood supply.

Explanation

Intraoperative TCD, which stands for Transcranial Doppler, is commonly used during Carotid Endartectomy surgery. This procedure involves removing plaque buildup from the carotid artery in order to improve blood flow to the brain. Intraoperative TCD is used during this surgery to monitor blood flow and detect any potential complications such as emboli or changes in cerebral blood flow. By using TCD, surgeons can ensure that the procedure is being performed successfully and that there are no adverse effects on the brain's blood supply.

148. Increasing the stimulation intensity will effect D-Wave by:

Decrease in latency

Increase in latency

Increasing the stimulation intensity will decrease the latency in D-Wave. This means that the time it takes for D-Wave to respond or process information will be reduced. Higher stimulation intensity leads to a faster response time, resulting in a decrease in latency.

Explanation

Increasing the stimulation intensity will decrease the latency in D-Wave. This means that the time it takes for D-Wave to respond or process information will be reduced. Higher stimulation intensity leads to a faster response time, resulting in a decrease in latency.

149. What is the wavelength in milliseconds of 60Hz noise?

16.67 milliseconds

33.33 milliseconds

3.6 milliseconds

144.98 milliseconds

The wavelength of a wave is the distance between two corresponding points on the wave. In the case of 60Hz noise, the frequency is given as 60Hz, which means that the wave completes 60 cycles per second. To find the wavelength in milliseconds, we can use the formula: wavelength = 1/frequency. Therefore, the wavelength of 60Hz noise would be 1/60Hz = 0.0167 seconds = 16.67 milliseconds.

Explanation

The wavelength of a wave is the distance between two corresponding points on the wave. In the case of 60Hz noise, the frequency is given as 60Hz, which means that the wave completes 60 cycles per second. To find the wavelength in milliseconds, we can use the formula: wavelength = 1/frequency. Therefore, the wavelength of 60Hz noise would be 1/60Hz = 0.0167 seconds = 16.67 milliseconds.

150. The sound pressure is increased by what factor if we increase the stimulation from 40db to 80db?

2

40

.2

4

If we increase the stimulation from 40db to 80db, the sound pressure is increased by a factor of 2. This means that the sound pressure is doubled when the stimulation is increased by 40db.

Explanation

If we increase the stimulation from 40db to 80db, the sound pressure is increased by a factor of 2. This means that the sound pressure is doubled when the stimulation is increased by 40db.

151. EMG from CN VI can be monitored by placing the subdermal needle electrodes in which muscle?

Lateral rectus

Inferior oblique

Superior oblique

Unmonitorable

The correct answer is "Lateral rectus." EMG stands for electromyography, which is a diagnostic procedure used to evaluate the health of muscles and the nerve cells that control them. CN VI refers to the sixth cranial nerve, also known as the abducens nerve, which controls the movement of the lateral rectus muscle. By placing subdermal needle electrodes in the lateral rectus muscle, one can monitor the EMG activity of CN VI.

Explanation

The correct answer is "Lateral rectus." EMG stands for electromyography, which is a diagnostic procedure used to evaluate the health of muscles and the nerve cells that control them. CN VI refers to the sixth cranial nerve, also known as the abducens nerve, which controls the movement of the lateral rectus muscle. By placing subdermal needle electrodes in the lateral rectus muscle, one can monitor the EMG activity of CN VI.

152. The epidural electrode should be placed where?

Above the dura

Below the dura

In the muscles

Above and below the dura

The epidural electrode should be placed above the dura. This is because the dura is the tough outermost layer of the spinal cord and brain, and placing the electrode above it allows for proper positioning and effective delivery of electrical stimulation. Placing the electrode below the dura or in the muscles would not target the desired area accurately, and placing it above and below the dura is not necessary as it may cause unnecessary complications.

Explanation

The epidural electrode should be placed above the dura. This is because the dura is the tough outermost layer of the spinal cord and brain, and placing the electrode above it allows for proper positioning and effective delivery of electrical stimulation. Placing the electrode below the dura or in the muscles would not target the desired area accurately, and placing it above and below the dura is not necessary as it may cause unnecessary complications.

153. The P14 is generated from which structure?

Caudal medial lemniscus

Sensory cortex

Brainstem

Brachial plexus

The P14 is generated from the caudal medial lemniscus.

Explanation

The P14 is generated from the caudal medial lemniscus.

154. The following agent will have the least effect on the motor evoked potential (MEP):

Inhalational

Neuromuscular blocker

Rocuronium

Succinylcholine

Inhalational agents refer to the gases or volatile liquids that are used to induce and maintain anesthesia. These agents are primarily used to depress the central nervous system and produce a state of unconsciousness. While they may have some effect on the motor evoked potential (MEP), they are generally considered to have the least effect compared to other agents like neuromuscular blockers such as Rocuronium and Succinylcholine. Neuromuscular blockers specifically target the neuromuscular junction and inhibit the transmission of nerve impulses, resulting in muscle relaxation and potentially a greater impact on MEP. Therefore, inhalational agents are the least likely to affect MEP.

Explanation

Inhalational agents refer to the gases or volatile liquids that are used to induce and maintain anesthesia. These agents are primarily used to depress the central nervous system and produce a state of unconsciousness. While they may have some effect on the motor evoked potential (MEP), they are generally considered to have the least effect compared to other agents like neuromuscular blockers such as Rocuronium and Succinylcholine. Neuromuscular blockers specifically target the neuromuscular junction and inhibit the transmission of nerve impulses, resulting in muscle relaxation and potentially a greater impact on MEP. Therefore, inhalational agents are the least likely to affect MEP.

155. The active input of the differential amplifier is also called:

A negative input

An inverting input

Both

None of the above

The active input of the differential amplifier is also called both a negative input and an inverting input because it is responsible for producing an output that is the opposite polarity of the input signal. This means that when a positive voltage is applied to the active input, the output will be a negative voltage, and vice versa. Therefore, both terms accurately describe the active input of a differential amplifier.

Explanation

The active input of the differential amplifier is also called both a negative input and an inverting input because it is responsible for producing an output that is the opposite polarity of the input signal. This means that when a positive voltage is applied to the active input, the output will be a negative voltage, and vice versa. Therefore, both terms accurately describe the active input of a differential amplifier.

156. SSEP is not recordable when cerebral perfusion drops below:

15 cc/min / 100 grams of tissue

20 cc/min / 100 grams of tissue

15 cc/min / 150 grams of tissue

25 cc/min / 150 grams of tissue

SSEP stands for somatosensory evoked potentials, which are electrical signals generated by the nervous system in response to sensory stimulation. These signals can be recorded and used to assess the integrity of the sensory pathways in the brain. The given answer states that SSEP is not recordable when cerebral perfusion drops below 15 cc/min / 100 grams of tissue. This means that if blood flow to the brain decreases below this threshold, the brain tissue may not receive enough oxygen and nutrients to function properly, leading to the inability to generate SSEP signals.

Explanation

SSEP stands for somatosensory evoked potentials, which are electrical signals generated by the nervous system in response to sensory stimulation. These signals can be recorded and used to assess the integrity of the sensory pathways in the brain. The given answer states that SSEP is not recordable when cerebral perfusion drops below 15 cc/min / 100 grams of tissue. This means that if blood flow to the brain decreases below this threshold, the brain tissue may not receive enough oxygen and nutrients to function properly, leading to the inability to generate SSEP signals.

157. Click stimulators should be delivered unilaterally or bilaterally?

Unilaterally

Bilaterally

Unilaterally refers to the delivery of click stimulators on one side only. This means that the stimulators are applied to either the left or right side of the body. Bilaterally, on the other hand, would mean that the stimulators are applied to both sides simultaneously. Without further context, it is difficult to determine the specific circumstances or reasons for choosing one approach over the other.

Explanation

Unilaterally refers to the delivery of click stimulators on one side only. This means that the stimulators are applied to either the left or right side of the body. Bilaterally, on the other hand, would mean that the stimulators are applied to both sides simultaneously. Without further context, it is difficult to determine the specific circumstances or reasons for choosing one approach over the other.

158. In a patient with hematocrit between 10-15%, SSEP waveforms will:

Increase in amplitude and decrease in latency

Disappear

Decrease in amplitude and increase in latency

Increase in latency

In a patient with a hematocrit between 10-15%, there is a decrease in the concentration of red blood cells in the blood. This decrease in red blood cells can lead to a decrease in the amplitude of SSEP (somatosensory evoked potential) waveforms. Additionally, the decrease in red blood cells can also affect the conduction of nerve signals, causing an increase in the latency or delay in the SSEP waveforms. Therefore, in this scenario, the SSEP waveforms would show a decrease in amplitude and an increase in latency.

Explanation

In a patient with a hematocrit between 10-15%, there is a decrease in the concentration of red blood cells in the blood. This decrease in red blood cells can lead to a decrease in the amplitude of SSEP (somatosensory evoked potential) waveforms. Additionally, the decrease in red blood cells can also affect the conduction of nerve signals, causing an increase in the latency or delay in the SSEP waveforms. Therefore, in this scenario, the SSEP waveforms would show a decrease in amplitude and an increase in latency.

159. Needle electrodes can be placed in these muscles in order to monitor cranial nerve IX:

Trapezius

Tongue

Soft palate glossopharyngeal

Vocal cords

Cranial nerve IX, also known as the glossopharyngeal nerve, innervates the muscles of the soft palate. Therefore, needle electrodes can be placed in these muscles to monitor the activity of cranial nerve IX. The other options listed (trapezius, tongue, vocal cords) are not directly innervated by cranial nerve IX, so placing needle electrodes in those muscles would not be useful for monitoring this specific cranial nerve.

Explanation

Cranial nerve IX, also known as the glossopharyngeal nerve, innervates the muscles of the soft palate. Therefore, needle electrodes can be placed in these muscles to monitor the activity of cranial nerve IX. The other options listed (trapezius, tongue, vocal cords) are not directly innervated by cranial nerve IX, so placing needle electrodes in those muscles would not be useful for monitoring this specific cranial nerve.

160. The reference input of the differential amplifier is also called:

A positive input

A non-inverting input

Both

None of the above

The reference input of a differential amplifier is also known as both a positive input and a non-inverting input. In a differential amplifier, the reference input is compared to the other input, which is typically the signal input. The reference input is connected to the non-inverting terminal of the amplifier, which means that it does not invert the signal polarity. At the same time, the reference input is usually biased to a positive voltage level, hence it is also referred to as the positive input. Therefore, the correct answer is both.

Explanation

The reference input of a differential amplifier is also known as both a positive input and a non-inverting input. In a differential amplifier, the reference input is compared to the other input, which is typically the signal input. The reference input is connected to the non-inverting terminal of the amplifier, which means that it does not invert the signal polarity. At the same time, the reference input is usually biased to a positive voltage level, hence it is also referred to as the positive input. Therefore, the correct answer is both.

161. If a circuit has an input voltage of 200 V and the resistance of 10 ohmsm what will be the current in the circuit?

20 amperes

2000 amperes

20 milliamperes

2000 milliamperes

The current in a circuit can be calculated using Ohm's Law, which states that the current (I) is equal to the voltage (V) divided by the resistance (R). In this case, the input voltage is given as 200 V and the resistance is 10 ohms. By dividing 200 V by 10 ohms, we get a current of 20 amperes.

Explanation

The current in a circuit can be calculated using Ohm's Law, which states that the current (I) is equal to the voltage (V) divided by the resistance (R). In this case, the input voltage is given as 200 V and the resistance is 10 ohms. By dividing 200 V by 10 ohms, we get a current of 20 amperes.

162. The electrodes contaminated with blood or body fluids of a patient with Creutzfeldt-Jakob disease (CJD) should be:

Disposed of by placement in appropriate infectious waste containers

Packaged and sent to the incinerator

Reported to the surgeon

Discarded the needle in the sharp bin

The correct answer is to dispose of the electrodes by placing them in appropriate infectious waste containers. This is because Creutzfeldt-Jakob disease (CJD) is a transmissible spongiform encephalopathy that can be spread through contaminated instruments. Therefore, it is important to handle and dispose of these contaminated electrodes properly to prevent the spread of the disease. Packaging and sending them to the incinerator is also a valid option for proper disposal. Reporting to the surgeon or discarding the needle in the sharp bin are not appropriate actions for the disposal of electrodes contaminated with CJD.

Explanation

The correct answer is to dispose of the electrodes by placing them in appropriate infectious waste containers. This is because Creutzfeldt-Jakob disease (CJD) is a transmissible spongiform encephalopathy that can be spread through contaminated instruments. Therefore, it is important to handle and dispose of these contaminated electrodes properly to prevent the spread of the disease. Packaging and sending them to the incinerator is also a valid option for proper disposal. Reporting to the surgeon or discarding the needle in the sharp bin are not appropriate actions for the disposal of electrodes contaminated with CJD.

163. Subdural electrodes made of platinum have what advantage?

Stability during stimulation & MRI compatible

Able to be stimulated at lower values

Flexibility for bundling electrodes together

None of these

Platinum subdural electrodes have the advantage of stability during stimulation and being MRI compatible. This means that they can withstand the electrical stimulation process without getting damaged and can also be used safely during MRI scans. This is beneficial as it allows for accurate and reliable data collection during stimulation and imaging procedures.

Explanation

Platinum subdural electrodes have the advantage of stability during stimulation and being MRI compatible. This means that they can withstand the electrical stimulation process without getting damaged and can also be used safely during MRI scans. This is beneficial as it allows for accurate and reliable data collection during stimulation and imaging procedures.

164. "HITS" is the abbrevation used for?

High Intensity Transient Signals

High Intensity Transcranial Signals

High Intensity Transient Sources

High Intraoperative Transient Signals

The term "HITS" is commonly used to refer to High Intensity Transient Signals. This abbreviation is used in various fields, such as engineering, telecommunications, and signal processing, to describe sudden and intense bursts of signals or energy.

Explanation

The term "HITS" is commonly used to refer to High Intensity Transient Signals. This abbreviation is used in various fields, such as engineering, telecommunications, and signal processing, to describe sudden and intense bursts of signals or energy.

165. Which artery is used for injection during WADA testing?

Internal Carotid Artery (ICA)

Middle Cerebral Artery (MCA)

Anterior Communicating Artery (Acomm)

Posterior Cerebral Artery (PCA)

During WADA testing, the Internal Carotid Artery (ICA) is used for injection. The ICA is a major artery that supplies blood to the brain. It is easily accessible and provides a direct route for the injection of substances used in the WADA test. The other arteries listed, such as the Middle Cerebral Artery (MCA), Anterior Communicating Artery (Acomm), and Posterior Cerebral Artery (PCA), are not typically used for injection during WADA testing.

Explanation

During WADA testing, the Internal Carotid Artery (ICA) is used for injection. The ICA is a major artery that supplies blood to the brain. It is easily accessible and provides a direct route for the injection of substances used in the WADA test. The other arteries listed, such as the Middle Cerebral Artery (MCA), Anterior Communicating Artery (Acomm), and Posterior Cerebral Artery (PCA), are not typically used for injection during WADA testing.

166. If there is a change in the neurophysiological data immediately after the incision what will be the probable cause?

Anesthesia

Positioning

Surgical error

Technical error

If there is a change in the neurophysiological data immediately after the incision, the probable cause would be anesthesia. Anesthesia can affect the functioning of the nervous system, leading to changes in neurophysiological data. It can cause a temporary interruption or alteration in nerve signals, resulting in changes in brain activity or nerve responses. This could manifest as changes in the neurophysiological data observed after the incision.

Explanation

If there is a change in the neurophysiological data immediately after the incision, the probable cause would be anesthesia. Anesthesia can affect the functioning of the nervous system, leading to changes in neurophysiological data. It can cause a temporary interruption or alteration in nerve signals, resulting in changes in brain activity or nerve responses. This could manifest as changes in the neurophysiological data observed after the incision.

167. Which of the following is an inhibitory neurotransmitter?

Acetylcholine

Epinephrine

GABA

All of the above

GABA (gamma-aminobutyric acid) is an inhibitory neurotransmitter. It functions by reducing the activity of neurons and decreasing the likelihood of an action potential being generated. This inhibitory effect helps to regulate and balance brain activity. Acetylcholine and epinephrine, on the other hand, are excitatory neurotransmitters that promote the generation of action potentials and stimulate neuronal activity. Therefore, GABA is the correct answer as it is the only inhibitory neurotransmitter listed.

Explanation

GABA (gamma-aminobutyric acid) is an inhibitory neurotransmitter. It functions by reducing the activity of neurons and decreasing the likelihood of an action potential being generated. This inhibitory effect helps to regulate and balance brain activity. Acetylcholine and epinephrine, on the other hand, are excitatory neurotransmitters that promote the generation of action potentials and stimulate neuronal activity. Therefore, GABA is the correct answer as it is the only inhibitory neurotransmitter listed.

168. What is the electrical line frequency in the operating rooms in Europe?

50Hz

60Hz

40Hz

70Hz

In Europe, the electrical line frequency in operating rooms is 50Hz. This means that the alternating current (AC) power supplied to the operating rooms is oscillating at a frequency of 50 cycles per second. This frequency is standard in Europe and is used for various electrical devices and systems, including those in operating rooms. It is important to have a consistent and reliable frequency for the proper functioning of electrical equipment and to ensure the safety of patients and healthcare professionals.

Explanation

In Europe, the electrical line frequency in operating rooms is 50Hz. This means that the alternating current (AC) power supplied to the operating rooms is oscillating at a frequency of 50 cycles per second. This frequency is standard in Europe and is used for various electrical devices and systems, including those in operating rooms. It is important to have a consistent and reliable frequency for the proper functioning of electrical equipment and to ensure the safety of patients and healthcare professionals.

169. The most prominent component of the electrocochleogram (ECochG), i.e. the AP, arises from:

Primary auditory nerve fibers

Auditory cortex

Pinna

(Cz) Vertex

The most prominent component of the electrocochleogram (ECochG), i.e. the AP, arises from the primary auditory nerve fibers. This is because the ECochG measures the electrical activity generated by the auditory system in response to sound stimuli. The primary auditory nerve fibers are responsible for transmitting auditory information from the cochlea to the brain, making them the main source of the AP component in the ECochG.

Explanation

The most prominent component of the electrocochleogram (ECochG), i.e. the AP, arises from the primary auditory nerve fibers. This is because the ECochG measures the electrical activity generated by the auditory system in response to sound stimuli. The primary auditory nerve fibers are responsible for transmitting auditory information from the cochlea to the brain, making them the main source of the AP component in the ECochG.

170. The normal paper speed for an EEG machine used in the diagnostic setting is:

30mm/second

20mm/minute

10mm/second

40mm/minute

The normal paper speed for an EEG machine used in the diagnostic setting is 30mm/second. This speed allows for a more detailed recording of brain activity, as it captures a higher number of data points per second. A faster paper speed would result in a less detailed recording, while a slower speed would provide a more generalized view of brain activity. Therefore, 30mm/second is the optimal speed for accurately analyzing and interpreting EEG recordings in a diagnostic setting.

Explanation

The normal paper speed for an EEG machine used in the diagnostic setting is 30mm/second. This speed allows for a more detailed recording of brain activity, as it captures a higher number of data points per second. A faster paper speed would result in a less detailed recording, while a slower speed would provide a more generalized view of brain activity. Therefore, 30mm/second is the optimal speed for accurately analyzing and interpreting EEG recordings in a diagnostic setting.

171. Burst suppression can be caused by what intravenous anesthetic agents?

Bolus of propofol

Bolus of thiopental

Both

Neither

Both a bolus of propofol and a bolus of thiopental can cause burst suppression. Burst suppression refers to a pattern of electroencephalogram (EEG) activity characterized by alternating periods of high amplitude bursts and periods of electrical silence. Both propofol and thiopental are intravenous anesthetic agents that can induce burst suppression as part of their pharmacological effects on the central nervous system.

Explanation

Both a bolus of propofol and a bolus of thiopental can cause burst suppression. Burst suppression refers to a pattern of electroencephalogram (EEG) activity characterized by alternating periods of high amplitude bursts and periods of electrical silence. Both propofol and thiopental are intravenous anesthetic agents that can induce burst suppression as part of their pharmacological effects on the central nervous system.

172. VEPs are not affected by inhalational agents.

False

True

Inhalational agents, such as volatile anesthetics, can affect Visual Evoked Potentials (VEPs). VEPs are electrical signals generated by the brain in response to visual stimuli, and they can be used to assess visual function. Inhalational agents can alter the amplitude and latency of VEPs, potentially leading to inaccurate test results. Therefore, the statement that VEPs are not affected by inhalational agents is false.

Explanation

Inhalational agents, such as volatile anesthetics, can affect Visual Evoked Potentials (VEPs). VEPs are electrical signals generated by the brain in response to visual stimuli, and they can be used to assess visual function. Inhalational agents can alter the amplitude and latency of VEPs, potentially leading to inaccurate test results. Therefore, the statement that VEPs are not affected by inhalational agents is false.

173. The blood supplied to the cochlea is through which artery?

Cochlear artery

Middle cerebral artery

Posterior cerebral artery

Basilar artery

The cochlea is a part of the inner ear responsible for hearing. The blood supply to the cochlea is through the cochlear artery. This artery specifically provides oxygenated blood to the structures of the cochlea, ensuring their proper functioning. The other arteries listed, such as the middle cerebral artery, posterior cerebral artery, and basilar artery, are not directly involved in supplying blood to the cochlea.

Explanation

The cochlea is a part of the inner ear responsible for hearing. The blood supply to the cochlea is through the cochlear artery. This artery specifically provides oxygenated blood to the structures of the cochlea, ensuring their proper functioning. The other arteries listed, such as the middle cerebral artery, posterior cerebral artery, and basilar artery, are not directly involved in supplying blood to the cochlea.

174. Localization of the central sulcus is based on what observation?

Median nerve SSEP polarity from sensory and motor gyri is reversed

Posterior tibial nerve SSEP polarity from sensory and motor gyri is reversed

Motor evoked potential MEP polarity from sensory and motor gyri is reversed

None of the above

The correct answer is "Median nerve SSEP polarity from sensory and motor gyri is reversed". This observation is used to localize the central sulcus. The central sulcus is a prominent fold in the cerebral cortex that separates the primary motor cortex (which controls voluntary movement) from the primary somatosensory cortex (which receives sensory information from the body). By observing the polarity reversal of the median nerve SSEP (somatosensory evoked potential) between the sensory and motor gyri, the central sulcus can be identified.

Explanation

The correct answer is "Median nerve SSEP polarity from sensory and motor gyri is reversed". This observation is used to localize the central sulcus. The central sulcus is a prominent fold in the cerebral cortex that separates the primary motor cortex (which controls voluntary movement) from the primary somatosensory cortex (which receives sensory information from the body). By observing the polarity reversal of the median nerve SSEP (somatosensory evoked potential) between the sensory and motor gyri, the central sulcus can be identified.

175. Localization of the motor cortex can be performed by:

Direct cortical stimulation

Direct sensory stimulation

Peripheral nerve stimulation

All of the above

Direct cortical stimulation is the most accurate method for localizing the motor cortex. It involves applying electrical stimulation directly to the surface of the brain to elicit motor responses. This allows for precise mapping of the motor cortex and identification of specific functional areas. Direct sensory stimulation and peripheral nerve stimulation can also provide some information about the motor cortex, but they are less precise and may not accurately reflect the actual cortical areas involved in motor function. Therefore, the best method for localizing the motor cortex is direct cortical stimulation.

Explanation

Direct cortical stimulation is the most accurate method for localizing the motor cortex. It involves applying electrical stimulation directly to the surface of the brain to elicit motor responses. This allows for precise mapping of the motor cortex and identification of specific functional areas. Direct sensory stimulation and peripheral nerve stimulation can also provide some information about the motor cortex, but they are less precise and may not accurately reflect the actual cortical areas involved in motor function. Therefore, the best method for localizing the motor cortex is direct cortical stimulation.

176. If the surgeons arm bumps into the sterile field, is it considered as contamination of the sterile field?

Yes

No

If the surgeon's arm bumps into the sterile field, it is considered as contamination of the sterile field. This is because any contact between non-sterile surfaces and the sterile field can introduce microorganisms and compromise its sterility. Even a slight touch or brush can potentially contaminate the sterile field, which is why surgeons and healthcare professionals are trained to maintain strict sterile techniques and avoid any unnecessary contact.

Explanation

If the surgeon's arm bumps into the sterile field, it is considered as contamination of the sterile field. This is because any contact between non-sterile surfaces and the sterile field can introduce microorganisms and compromise its sterility. Even a slight touch or brush can potentially contaminate the sterile field, which is why surgeons and healthcare professionals are trained to maintain strict sterile techniques and avoid any unnecessary contact.

177. In a fire emergency, R.A.C.E. stands for:

Rescue Alarm Call Extinguish

Run Alarm Circulate Extend

Resuscitate Alert Calm Extinguish

Rescue Alert Call Extinguish

R.A.C.E. stands for Rescue Alarm Call Extinguish. In a fire emergency, the first step is to rescue anyone who may be in immediate danger. Then, the alarm should be sounded to alert others and initiate the evacuation process. Next, the fire department should be called to report the emergency and provide necessary information. Finally, if it is safe to do so, attempts can be made to extinguish the fire using appropriate methods or equipment.

Explanation

R.A.C.E. stands for Rescue Alarm Call Extinguish. In a fire emergency, the first step is to rescue anyone who may be in immediate danger. Then, the alarm should be sounded to alert others and initiate the evacuation process. Next, the fire department should be called to report the emergency and provide necessary information. Finally, if it is safe to do so, attempts can be made to extinguish the fire using appropriate methods or equipment.

178. How many trials should be averaged for BAEP recordings?

1000-4000

500-2000

100-300

2000-5000

The range of 1000-4000 trials should be averaged for BAEP recordings. This range is likely determined based on the specific requirements and characteristics of BAEP recordings. Averaging a large number of trials helps to reduce the noise and improve the signal-to-noise ratio, resulting in more accurate and reliable recordings. However, averaging too few trials may not provide enough data for a clear and consistent signal. Therefore, the range of 1000-4000 trials is considered appropriate for obtaining meaningful BAEP recordings.

Explanation

The range of 1000-4000 trials should be averaged for BAEP recordings. This range is likely determined based on the specific requirements and characteristics of BAEP recordings. Averaging a large number of trials helps to reduce the noise and improve the signal-to-noise ratio, resulting in more accurate and reliable recordings. However, averaging too few trials may not provide enough data for a clear and consistent signal. Therefore, the range of 1000-4000 trials is considered appropriate for obtaining meaningful BAEP recordings.

179. Needle electrodes can be placed in this muscle in order to monitor cranial nerve IV:

Superior oblique

Inferior oblique

Massater

Frontalis

The superior oblique muscle is responsible for the movement of the eye and is innervated by cranial nerve IV, also known as the trochlear nerve. By placing needle electrodes in the superior oblique muscle, healthcare professionals can monitor the activity and function of cranial nerve IV. This muscle is particularly important for controlling eye movements, especially downward and inward rotations.

Explanation

The superior oblique muscle is responsible for the movement of the eye and is innervated by cranial nerve IV, also known as the trochlear nerve. By placing needle electrodes in the superior oblique muscle, healthcare professionals can monitor the activity and function of cranial nerve IV. This muscle is particularly important for controlling eye movements, especially downward and inward rotations.

180. An IOM system with 12bit of vertical resolution (12-bit ADC) will have how many data points?

4096

2^12

Both

Neither

An IOM system with 12-bit of vertical resolution means that the system has a 12-bit analog-to-digital converter (ADC). A 12-bit ADC can represent 2^12 or 4096 different data points. Therefore, the correct answer is both 4096 and 2^12.

Explanation

An IOM system with 12-bit of vertical resolution means that the system has a 12-bit analog-to-digital converter (ADC). A 12-bit ADC can represent 2^12 or 4096 different data points. Therefore, the correct answer is both 4096 and 2^12.

181. What is the interstimulus interval (ISI) for a 400Hz stimulation?

2.5 milliseconds

4 milliseconds

8 milliseconds

1.25 milliseconds

The interstimulus interval (ISI) refers to the time interval between two consecutive stimuli. In this question, the correct answer is 2.5 milliseconds. This means that there is a gap of 2.5 milliseconds between each stimulation when the frequency is 400Hz. This information helps in understanding the timing and spacing of the stimuli, which can be important in various fields such as psychology, neuroscience, and sensory perception studies.

Explanation

The interstimulus interval (ISI) refers to the time interval between two consecutive stimuli. In this question, the correct answer is 2.5 milliseconds. This means that there is a gap of 2.5 milliseconds between each stimulation when the frequency is 400Hz. This information helps in understanding the timing and spacing of the stimuli, which can be important in various fields such as psychology, neuroscience, and sensory perception studies.

182. The temporal nerve is a branch of which cranial nerve?

Facial nerve (CN VII)

Trigeminal nerve (CN V)

Trochlear nerve (CN IV)

Glossopharyngeal nerve (CN IX)

The temporal nerve is a branch of the facial nerve (CN VII). The facial nerve is responsible for controlling the muscles of facial expression and also carries sensory information from the taste buds on the anterior two-thirds of the tongue. The temporal nerve specifically innervates the muscles that control the movement of the forehead and scalp, allowing for actions such as raising the eyebrows and wrinkling the forehead.

Explanation

The temporal nerve is a branch of the facial nerve (CN VII). The facial nerve is responsible for controlling the muscles of facial expression and also carries sensory information from the taste buds on the anterior two-thirds of the tongue. The temporal nerve specifically innervates the muscles that control the movement of the forehead and scalp, allowing for actions such as raising the eyebrows and wrinkling the forehead.

183. Meniere's disease can be treated by resection of which cranial nerve?

Vestibular portion of the CN VIII

Buccal portion of the CN VII

Zygomatic portion of CN VII

Auditory portion of the CN VIII

Meniere's disease is a disorder of the inner ear that affects balance and hearing. The symptoms include vertigo, hearing loss, tinnitus, and a feeling of fullness in the affected ear. The vestibular portion of the CN VIII, also known as the vestibulocochlear nerve, is responsible for transmitting information about balance and spatial orientation from the inner ear to the brain. By resecting or removing this portion of the nerve, the abnormal signals causing the symptoms of Meniere's disease can be eliminated or reduced, providing relief to the patient.

Explanation

Meniere's disease is a disorder of the inner ear that affects balance and hearing. The symptoms include vertigo, hearing loss, tinnitus, and a feeling of fullness in the affected ear. The vestibular portion of the CN VIII, also known as the vestibulocochlear nerve, is responsible for transmitting information about balance and spatial orientation from the inner ear to the brain. By resecting or removing this portion of the nerve, the abnormal signals causing the symptoms of Meniere's disease can be eliminated or reduced, providing relief to the patient.

184. Post central somatosensory gyrus is localized by identifying which peak?

A negative peak with latency around 20 milliseconds

A negative peak with latency around 22 milliseconds

A positive peak with latency around 20 milliseconds

A positive peak with latency around 22 milliseconds

The post central somatosensory gyrus is localized by identifying a negative peak with a latency around 20 milliseconds. This means that when studying brain activity, researchers can pinpoint the specific area by observing a dip in electrical activity around 20 milliseconds after a stimulus is applied. This negative peak is characteristic of the post central somatosensory gyrus and helps to identify its location in the brain.

Explanation

The post central somatosensory gyrus is localized by identifying a negative peak with a latency around 20 milliseconds. This means that when studying brain activity, researchers can pinpoint the specific area by observing a dip in electrical activity around 20 milliseconds after a stimulus is applied. This negative peak is characteristic of the post central somatosensory gyrus and helps to identify its location in the brain.

185. The suitable, recommended low and high cut filter for median nerve cortical sensory mapping should be:

LF = 1-30Hz and HF = 250-3,000Hz

LF = 1-10Hz and HF = 250-3,000Hz

LF = 1-30Hz and HF = 250-300Hz

LF = 1-10Hz and HF = 250-300Hz

The suitable, recommended low and high cut filter for median nerve cortical sensory mapping should be LF = 1-30Hz and HF = 250-3,000Hz. This range of frequencies allows for the detection and analysis of sensory signals originating from the median nerve. The low cut filter at 1Hz ensures that any baseline drift or unwanted low-frequency noise is eliminated, while the high cut filter at 3,000Hz prevents any high-frequency noise or artifacts from affecting the mapping results. This specific range of frequencies is known to provide accurate and reliable sensory mapping of the median nerve.

Explanation

The suitable, recommended low and high cut filter for median nerve cortical sensory mapping should be LF = 1-30Hz and HF = 250-3,000Hz. This range of frequencies allows for the detection and analysis of sensory signals originating from the median nerve. The low cut filter at 1Hz ensures that any baseline drift or unwanted low-frequency noise is eliminated, while the high cut filter at 3,000Hz prevents any high-frequency noise or artifacts from affecting the mapping results. This specific range of frequencies is known to provide accurate and reliable sensory mapping of the median nerve.

186. Distance from sterile field should be at least:

12 inches

6 inches

18 inches

22 inches

The distance from the sterile field should be at least 12 inches to minimize the risk of contamination. This distance ensures that any movement or activity around the sterile field does not accidentally come into contact with the sterile area, reducing the chances of introducing harmful bacteria or other contaminants. Keeping a sufficient distance helps maintain the integrity of the sterile field and promotes a safe and hygienic environment for medical procedures.

Explanation

The distance from the sterile field should be at least 12 inches to minimize the risk of contamination. This distance ensures that any movement or activity around the sterile field does not accidentally come into contact with the sterile area, reducing the chances of introducing harmful bacteria or other contaminants. Keeping a sufficient distance helps maintain the integrity of the sterile field and promotes a safe and hygienic environment for medical procedures.

187. The most common source of airborne bacteria in the operating room is from:

Dead skin particles of the OR staff

Patient’s own endogenous flora

Contaminated surgical instrumentation

Dust particles from air ducts

Dead skin particles of the OR staff are the most common source of airborne bacteria in the operating room. When staff members shed dead skin cells, these particles can become airborne and carry bacteria with them. This can pose a risk of contamination to the surgical site and increase the chances of surgical site infections. Therefore, proper hygiene practices and regular cleaning of the operating room are crucial in minimizing the presence of airborne bacteria.

Explanation

Dead skin particles of the OR staff are the most common source of airborne bacteria in the operating room. When staff members shed dead skin cells, these particles can become airborne and carry bacteria with them. This can pose a risk of contamination to the surgical site and increase the chances of surgical site infections. Therefore, proper hygiene practices and regular cleaning of the operating room are crucial in minimizing the presence of airborne bacteria.

188. What is the recommended bandpass filter settings for BAEP recordings?

10-30Hz to 2500-3000Hz

10-50Hz to 1500-2000Hz

1-30Hz to 2000-3000Hz

1-30Hz to 2500Hz

The recommended bandpass filter settings for BAEP (Brainstem Auditory Evoked Potential) recordings are 10-30Hz to 2500-3000Hz. This range allows for the filtering of unwanted low-frequency and high-frequency noise, while still capturing the relevant auditory signals within the specified frequency range.

Explanation

The recommended bandpass filter settings for BAEP (Brainstem Auditory Evoked Potential) recordings are 10-30Hz to 2500-3000Hz. This range allows for the filtering of unwanted low-frequency and high-frequency noise, while still capturing the relevant auditory signals within the specified frequency range.

189. The Buccal nerve is a branch of the trigeminal nerve.

False

True

The Buccal nerve is not a branch of the trigeminal nerve. The Buccal nerve is actually a branch of the mandibular division of the trigeminal nerve, specifically the buccal branch of the mandibular nerve. This nerve provides sensory innervation to the cheek and buccal mucosa.

Explanation

The Buccal nerve is not a branch of the trigeminal nerve. The Buccal nerve is actually a branch of the mandibular division of the trigeminal nerve, specifically the buccal branch of the mandibular nerve. This nerve provides sensory innervation to the cheek and buccal mucosa.

190. The generator of Wave II of the BAEP repsonse is:

Proximal Auditory Nerve

Lateral Lemniscus

Cochlear Nucleus

Inferior Colliculus

The correct answer is the Proximal Auditory Nerve. This nerve is responsible for generating Wave II of the BAEP (Brainstem Auditory Evoked Potential) response. The BAEP is a test that measures the electrical activity in the brain in response to sound stimulation. Wave II represents the electrical activity generated by the Proximal Auditory Nerve as it carries auditory information from the cochlea to the brainstem. The other options listed, such as the Lateral Lemniscus, Cochlear Nucleus, and Inferior Colliculus, are also involved in the auditory pathway, but they are not specifically responsible for generating Wave II of the BAEP response.

Explanation

The correct answer is the Proximal Auditory Nerve. This nerve is responsible for generating Wave II of the BAEP (Brainstem Auditory Evoked Potential) response. The BAEP is a test that measures the electrical activity in the brain in response to sound stimulation. Wave II represents the electrical activity generated by the Proximal Auditory Nerve as it carries auditory information from the cochlea to the brainstem. The other options listed, such as the Lateral Lemniscus, Cochlear Nucleus, and Inferior Colliculus, are also involved in the auditory pathway, but they are not specifically responsible for generating Wave II of the BAEP response.

191. Why should filter settings not be changed during the surgery?

It will change the latency of evoked responses

It will change the gain of evoked responses

It will change the stimulus levels of evoked responses

It will change the baselines of evoked responses

Changing the filter settings during surgery can alter the latency of evoked responses. Latency refers to the time it takes for a response to occur after a stimulus is presented. By changing the filter settings, the processing of the signals can be affected, leading to a delay in the evoked responses. This can be problematic during surgery as accurate and timely responses are crucial for monitoring the patient's condition and making informed decisions. Therefore, it is important to maintain consistent filter settings to ensure reliable and accurate data during the surgery.

Explanation

Changing the filter settings during surgery can alter the latency of evoked responses. Latency refers to the time it takes for a response to occur after a stimulus is presented. By changing the filter settings, the processing of the signals can be affected, leading to a delay in the evoked responses. This can be problematic during surgery as accurate and timely responses are crucial for monitoring the patient's condition and making informed decisions. Therefore, it is important to maintain consistent filter settings to ensure reliable and accurate data during the surgery.

192. BAER wave III is recording from:

Cochlear nucleus

The proximal portion of the auditory nerve

The distal portion of the auditory nerve

Inferior colliculus

BAER wave III is recorded from the cochlear nucleus. The cochlear nucleus is the first processing center for auditory information in the brainstem. It receives input from the auditory nerve and plays a crucial role in the initial processing and integration of sound signals. Wave III of the BAER (Brainstem Auditory Evoked Response) represents the electrical activity generated by the cochlear nucleus in response to an auditory stimulus. Therefore, the correct answer is the cochlear nucleus.

Explanation

BAER wave III is recorded from the cochlear nucleus. The cochlear nucleus is the first processing center for auditory information in the brainstem. It receives input from the auditory nerve and plays a crucial role in the initial processing and integration of sound signals. Wave III of the BAER (Brainstem Auditory Evoked Response) represents the electrical activity generated by the cochlear nucleus in response to an auditory stimulus. Therefore, the correct answer is the cochlear nucleus.

193. Which cranial nerve function will be compromised by the disease called "Tic Douloureux"?

Trigeminal (CN V)

Facial (CN VII)

Vagus (CN X)

Spinal Accessory (CN XI)

Tic Douloureux, also known as trigeminal neuralgia, is a disease that affects the trigeminal nerve (CN V). This nerve is responsible for transmitting sensory information from the face to the brain, as well as controlling the muscles involved in chewing. Therefore, if someone has Tic Douloureux, it means that their trigeminal nerve function is compromised, leading to severe facial pain and muscle spasms.

Explanation

Tic Douloureux, also known as trigeminal neuralgia, is a disease that affects the trigeminal nerve (CN V). This nerve is responsible for transmitting sensory information from the face to the brain, as well as controlling the muscles involved in chewing. Therefore, if someone has Tic Douloureux, it means that their trigeminal nerve function is compromised, leading to severe facial pain and muscle spasms.

194. Peripheral Conduction Time (PCT) for posterior tibial nerve is calculated between which peaks?

PF-LP

LP-N37

P31-P37

N34-P37

The correct answer is PF-LP. Peripheral Conduction Time (PCT) for the posterior tibial nerve is calculated between the peaks labeled PF and LP.

Explanation

The correct answer is PF-LP. Peripheral Conduction Time (PCT) for the posterior tibial nerve is calculated between the peaks labeled PF and LP.

195. The filter roll-off for BAEP should not exceed what values for low and high frequency filters?

12dB/octave for low frequency filter & 24dB/octave for high frequency filter

10dB/octave for low frequency filter & 22dB/octave for high frequency filter

12dB/octave for low frequency filter & 22dB/octave for high frequency filter

10dB/octave for low frequency filter & 24dB/octave for high frequency filter

The filter roll-off for BAEP should not exceed 12dB/octave for the low frequency filter and 24dB/octave for the high frequency filter. This means that the rate at which the filter attenuates the frequencies beyond its cutoff point should not be steeper than these values. A steeper roll-off can result in unwanted distortion or artifacts in the filtered signal, compromising the accuracy and reliability of BAEP measurements. Therefore, it is important to adhere to these specific roll-off values to ensure optimal filtering in BAEP testing.

Explanation

The filter roll-off for BAEP should not exceed 12dB/octave for the low frequency filter and 24dB/octave for the high frequency filter. This means that the rate at which the filter attenuates the frequencies beyond its cutoff point should not be steeper than these values. A steeper roll-off can result in unwanted distortion or artifacts in the filtered signal, compromising the accuracy and reliability of BAEP measurements. Therefore, it is important to adhere to these specific roll-off values to ensure optimal filtering in BAEP testing.

196. Compount auditory nerve action potientals (C-ANAP) can be recording by using what type of electrode?

Cueva nerve electrode

Subdermal electrode

Surface electrode

Hook wire

The correct answer is Cueva nerve electrode. C-ANAPs are compound auditory nerve action potentials, which are electrical signals generated by the auditory nerve in response to sound. To record these potentials, a specialized electrode called the Cueva nerve electrode is used. This electrode is designed to be inserted directly into the auditory nerve, allowing for precise and accurate recording of the C-ANAPs. Subdermal and surface electrodes are not specifically designed for recording C-ANAPs, and a hook wire is not commonly used for this purpose.

Explanation

The correct answer is Cueva nerve electrode. C-ANAPs are compound auditory nerve action potentials, which are electrical signals generated by the auditory nerve in response to sound. To record these potentials, a specialized electrode called the Cueva nerve electrode is used. This electrode is designed to be inserted directly into the auditory nerve, allowing for precise and accurate recording of the C-ANAPs. Subdermal and surface electrodes are not specifically designed for recording C-ANAPs, and a hook wire is not commonly used for this purpose.

197. An 8-bit analog to digital filter will have how many data points?

256

2^8

2 log 8

All of the above

An 8-bit analog-to-digital converter (ADC) will have 2^8 data points. Each bit doubles the number of possible states, so with 8 bits, there are 2^8 = 256 possible data points. Therefore, the correct answer is 256.

Explanation

An 8-bit analog-to-digital converter (ADC) will have 2^8 data points. Each bit doubles the number of possible states, so with 8 bits, there are 2^8 = 256 possible data points. Therefore, the correct answer is 256.

198. The most frequent source of patient infection in the operating room is from:

Patient’s own endogenous flora

Dead skin particles of the OR staff

Contamination of the surgical instrumentation

Dust particles from air ducts

The most frequent source of patient infection in the operating room is from the patient's own endogenous flora. Endogenous flora refers to the microorganisms that naturally reside in or on the body. These microorganisms can potentially cause infection if they enter a sterile area during surgery. It is important for healthcare professionals to take precautions to minimize the risk of introducing the patient's own flora into the surgical site.

Explanation

The most frequent source of patient infection in the operating room is from the patient's own endogenous flora. Endogenous flora refers to the microorganisms that naturally reside in or on the body. These microorganisms can potentially cause infection if they enter a sterile area during surgery. It is important for healthcare professionals to take precautions to minimize the risk of introducing the patient's own flora into the surgical site.

199. What is the maximum allowable leakage current through patient leads with 120AC applied?

10ums

100ums

1ums

0.1ums

The maximum allowable leakage current through patient leads with 120AC applied is 10ums. This means that any leakage current exceeding 10ums would not be considered safe or within the acceptable range.

Explanation

The maximum allowable leakage current through patient leads with 120AC applied is 10ums. This means that any leakage current exceeding 10ums would not be considered safe or within the acceptable range.

200. The oldest neuromuscular blocking agent is:

Curare

Vecuronium

Rocuronium

Succinylcholine

Curare is the oldest neuromuscular blocking agent. It is a naturally occurring plant extract used by indigenous people in South America for hunting. Curare works by blocking the transmission of nerve impulses at the neuromuscular junction, leading to muscle relaxation and paralysis. It has been used in medicine as a muscle relaxant during surgery and for the treatment of conditions such as tetanus and spasticity. Although newer agents like vecuronium, rocuronium, and succinylcholine have been developed, curare remains historically significant as the first neuromuscular blocking agent to be discovered and used.

Explanation

Curare is the oldest neuromuscular blocking agent. It is a naturally occurring plant extract used by indigenous people in South America for hunting. Curare works by blocking the transmission of nerve impulses at the neuromuscular junction, leading to muscle relaxation and paralysis. It has been used in medicine as a muscle relaxant during surgery and for the treatment of conditions such as tetanus and spasticity. Although newer agents like vecuronium, rocuronium, and succinylcholine have been developed, curare remains historically significant as the first neuromuscular blocking agent to be discovered and used.

Cnim Abret Practice Questions

1. Transforaminal lumbar interbody fusion (TLIF) surgical procedure is related to the lumbar region.

2.

What first name or nickname would you like us to use?

2. In order to prevent any tongue injuries due to TcMEP stimulation we should always use:

3. Patient privacy act is known as:

4. Electrode placement on the scalp for SSEP is based on:Which one do you like?

5. If you drop a subdermal needle on the OR floor, what should you do?

6. After the surgical procedure, where should the needle electrodes be discarded?

7. The back of the surgeons gown is considered as non-sterile.

8. Train of four (TOF) from the foot should be monitored from which muscle?

9. You are on the way to the OR for surgery along with the surgeon. The surgeon begins to ask questions about a specific patient by name from the previous week. Since the other people in the elevator are all hospital staff, you can discuss the patient history to save valuable time in the OR.

10. Latency and/or amplitude changes in SSEP responses can result from:

11. When performing EEG in patients suspected of or diagnosed with an infectious disease, the technologist should always:

12. What is common mode rejection (CMR)?

13. The condition due to incomplete closure of the spinal cord is called?

14. The progressive central nervous system disease that affects myelin and causes weakness, vision loss, fatigue, and imparred coordination is known as:

15. A disease meaning "fused joint" is called:

16. When should hands be washed?

17. A direct activation of corticospinal tract produces a D-Wave.

18. The short acting muscle relaxant often given for intubation is:

19. Stimulation of the motor roots of Trigeminal nerve (CN V) produces a muscle response from:

20. EMG monitoring from the S3 root must include which muscle?

21. If the patients signals are lost and recovered during the surgery what will be the post operative outcome?

22. The primary motor area is located where in the brain?

23. An indirect activation of corticospinal tract produces an I-Wave.

24. Occipital lobe is responsible for processing which evoked response?

25. Mapping of the language area is done by stimulating which areas of the cortex?

26. What is the electrical line frequency in the operating rooms in the USA?

27. Where is the best place to put a ground electrode in order to reduce any stimulation artifact.

28. The first component of BAER does not arise in the brainstem but the auditory nerve.

29. Which intravenous anesthetic agents cause an increase in amplitude of SSEP & TcMEP responses?

30. Which one of the following agents is an opioid:

31. What anesthetics are contraindicated when monitoring TcMEP?

32. A reponse recorded by an epidural electrode due to direct activation of corticospinal tract is known as:

33. A forward movement of lumbar vertebrae over the vertebrae one level below is known as:

34. We usually see after discharges (Ads) at which stage?

35. If TOF is done from the posterior tibial nerve at the ankle which muscle will be ideal for recording?

36. If the surgeon's arm touches the IOM equipment table, it will become unsterile.

37. Which cranial nerves should be monitored for a cerebellopontine angle (CPA) tumor less than 2 cm in size?

38. During a continuous cautery what should we do with the recording?

39. The electrode impedance can be measured using what device?

40. The machine used in the operating room that causes suction, washes, and filters blood so it can be given to the patient is called a:

41. If it not possible to stimulate the posterior tibial nerve, which nerve should be used as an alternate?

42. The C5 nerve root innervates which muscles?

43. Lower limb SSEPs are transmitted via:

44. What is the blood supply of cortical responses elicited by median nerve stimulation?

45. Neuromuscular blocking agents can be helpful in recording of:

46. Compression or sustained traction of a nerve appears in spontaneous EMG recordings as a:

47. Pedicle screws are placed in order to perform what procedure?

48. Bloodborne pathogens may cause which of the following diseases:

49. The part of the spine removed to place an epidural electrode is known as:

50. Which cranial nerve function will be compromised by the disease called "Bell's Palsy"?

51. An interbody cage is placed to:

52. What is the probable cause of noise if it is observed in all channels?

53. An inflammation of a vertebrae or vertebral joint is known as:

54. The warning criteria for SSEP changes have been generally accepted as: Which one do you like?

55. Obligatory waves of the posterior tibial nerve (PTN) are:

56. A selective dorsal root rhizotomy is used for the treatment of:

57. The areas of the skin supplied by cutaneous branches of the spinal nerves are known as:

58. Upper limb SSEPs are transmitted via:

59. EMG monitoring from the S1 root muscle include which muscle?

60. Which nerve should be stimulated for lower limb SSEP as recommended by ACNS guidelines for short-latency SSEP?

61. The N20 responses is generated from which structure?

62. Lumbar Potential (LP) is a stationary (non-propagated) potential.

63. Intraoperative facial nerve monitoring was a result of a high incidence of post operative facial nerve weakness after acoustic nerve surgeries.

64. A microvascular decompression (MVD) of the cranial nerve is:

65. TCD is used for measuring blood flow velocity not blood flow. True Which one do you like?

66. In which procedure is lower extremity triggered EMG used to identify rootlets that can cause spasticity?

67. Which of the following structures is not part of the brainstem:

68. The ratio of an output voltage to an input voltage of the amplifier is known as:

69. If your amplifier gets saturated during the exposure part of the surgery, how should you solve it?

70. Evoked responses produced by unpatterned visual stimulation are known as:

71. Pattern Shift VEPs (PVEP) are affected by drowsiness.

72. What body functions will be affected if the patient is diagnosed with apraxia?

73. The N18 subcortical response is a near field or far field response?

74. Ohm's law is mathematically expressed as:

75. TIVA is an abbreviation for:

76. Needle electrodes can be placed in this muscles in order to monitor cranial nerve V:

77. What other modality should be included in addition to BAER for vestibular schwannoma surgery?

81. The _ nerve should be stimulated __ to the side of cortical mapping.