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Computed Tomography Quizzes & Trivia

Computed tomography review


Questions and Answers
  • 1. 
    All human  tissues and organs originates from primary germ layers.which germ layer forms the central nervous system
    • A. 

      Endoderm

    • B. 

      Macroderm

    • C. 

      Mesoderm

    • D. 

      Ectoderm

  • 2. 
    Which cranial nerve has the widest distribution
    • A. 

      Trigeminal

    • B. 

      Hypoglossal

    • C. 

      Vagus

    • D. 

      Glossopharyngial

  • 3. 
    What is an important funtion of the choroid plexus
    • A. 

      Separates the cerebral hemispheres

    • B. 

      To protect the brains surface

    • C. 

      To produce cerebral spinal fluid

    • D. 

      To provide comunication between right and left cerebellum

  • 4. 
    The normal range of respiration for an adult is
    • A. 

      5-10 breaths per minute

    • B. 

      12-20 breaths per minute

    • C. 

      20-30 breaths per minute

    • D. 

      35-50 breaths per minute

  • 5. 
    Which of the following is a parenteral route of medication administration
    • A. 

      Sublingual

    • B. 

      Intramuccular

    • C. 

      Transdermal

    • D. 

      Oral

  • 6. 
    The preparation for a contrast ct exam of a patient with a prior alergic reaction may include
    • A. 

      Premedication with steroids and antihestamines

    • B. 

      A negative contrast agent

    • C. 

      Increase of fluid intake for 24 hours

    • D. 

      Refraining from urinating for 2 hours before the test

  • 7. 
    A common injection site for contrast would be
    • A. 

      Cephalic vein

    • B. 

      Antecubital vein

    • C. 

      Basilic vein

    • D. 

      All of the above

  • 8. 
    Which of these technical factors would directly effect patient dose
    • A. 

      Matrix size

    • B. 

      Algorithm

    • C. 

      Mas

    • D. 

      Window level

  • 9. 
    Preleminary questions before injection of iv contrast would include1. renal function2. allergic history3 cardiac history
    • A. 

      1 only

    • B. 

      1 and 2 only

    • C. 

      3 only

    • D. 

      1, 2, and 3

  • 10. 
    The term__________ refers to the number of ions formed when a substance disassociates in solution. it is used to determine the biological effects of iv contrast
    • A. 

      Concentration

    • B. 

      Osmolality

    • C. 

      Solubility

    • D. 

      Iodination

  • 11. 
    Which of the following lab values can be used to eval renal function
    • A. 

      Bun

    • B. 

      Creatinine

    • C. 

      Ptt

    • D. 

      A&b

  • 12. 
    An infection a patient aquires during their hospital (common to that hospital) stay is called
    • A. 

      Blood-borne

    • B. 

      Nosocomial

    • C. 

      Iatrogenic

    • D. 

      Staphylococcal

  • 13. 
    A contrast material that does not dissassotiate into charged particles in solution is called
    • A. 

      Neutral

    • B. 

      Non ionic

    • C. 

      Osmolar

    • D. 

      Ionic

  • 14. 
    The average range for adult bun levels is
    • A. 

      1-4 mg/dl

    • B. 

      5-20 mg/dl

    • C. 

      23-30 mg/dl

    • D. 

      45-60mg/dl

  • 15. 
    A condition in which cerebral ischemia is caused by systemic hypotention
    • A. 

      Vasovagal reaction

    • B. 

      Myocardial infarction

    • C. 

      Transient ischemic attack

    • D. 

      Hydrocephalus

  • 16. 
    Which interaction between xray beam and matter results in the largest pt. dose
    • A. 

      Characteristic

    • B. 

      Compton's scatter

    • C. 

      Bremsstrahlung

    • D. 

      Photoelectric effect

  • 17. 
    What is a common medication used to sedate small children in order to do a ct exam
    • A. 

      Chloral hydrate

    • B. 

      Lithium

    • C. 

      Diazipam(valium)

    • D. 

      Secobarbital sodium

  • 18. 
    The purpose of iv contrast adminisration is
    • A. 

      Increase the contrast of adjacent structures

    • B. 

      Increase beam attenuation of enhanced structures

    • C. 

      Increase the cost to the patient

    • D. 

      A and b

  • 19. 
    The adult spinal cord ends at what vertebral level
    • A. 

      L1-2

    • B. 

      Ll3-4

    • C. 

      L5

    • D. 

      Superior portion of the coccyx

  • 20. 
    The portion of the nephron that filters waste material from the blood plasma is
    • A. 

      Afferent arteriole

    • B. 

      Proximal tubule

    • C. 

      Efferent arteriole

    • D. 

      Glomerulus

  • 21. 
    Which of the paranasal sinuses is the last to develope
    • A. 

      Frontal

    • B. 

      Ethmoidal

    • C. 

      Sphenoidal

    • D. 

      Maxillary

  • 22. 
    What is an important function of the choroid plexus
    • A. 

      To divide the cerebellum

    • B. 

      To produce cerebrospinal fluid

    • C. 

      To protect the brain

    • D. 

      To provide comunication between the cerebella and cerebrum

  • 23. 
    What is the only movable joint in the cranium
    • A. 

      Maxilary

    • B. 

      Zigomatic

    • C. 

      Temporomandibular

    • D. 

      Sphenomandibular

  • 24. 
    Which gland can be palpated by placing the index and middle fingers just anterior and inferior to the earlobe
    • A. 

      Parotid

    • B. 

      Parathyroid

    • C. 

      Submandibular

    • D. 

      Sublingual

  • 25. 
    The digital to analog converter insures that the data is free from artifacts and contain enough usable data. this is known as
    • A. 

      Formatting

    • B. 

      Continuoussampling

    • C. 

      Quality conversion

    • D. 

      Preprocessing

  • 26. 
    Which artifact indicates a detector is defective
    • A. 

      Aliasing

    • B. 

      Noise

    • C. 

      Ring

    • D. 

      Partial volume averaging

  • 27. 
    What does fourier transform calculate
    • A. 

      Homogeneity of the xray beam

    • B. 

      The lenghth of time for the xrays to pass through the patient and strike the detectors

    • C. 

      The probability that the xray beam will be deflected

    • D. 

      The distance between the patient and the detectors

  • 28. 
    What does the slice thickness affect
    • A. 

      How the details of the exam will appear

    • B. 

      Beam energy

    • C. 

      The algorythem for backprojection

    • D. 

      Matrix size

  • 29. 
    What determines the focal spot size
    • A. 

      Scan field of veiw

    • B. 

      Cathode filiment and anode target angle

    • C. 

      Linear attenuation coeficient and pitch

    • D. 

      Prepatient collimator

  • 30. 
    What allows continuous xray production in todays ct scanners
    • A. 

      Stationary rotors

    • B. 

      Rorating anodes

    • C. 

      Rotating detector array

    • D. 

      Pencil beam geomitry

  • 31. 
    The analog to digital converter contains several parts,which part of the adc asigns the binary numbers that become the digital signal
    • A. 

      Sampler

    • B. 

      Quantisizer

    • C. 

      Dispencer

    • D. 

      Coder

  • 32. 
    The scan field of veiw is mostly responsible for
    • A. 

      Pitch

    • B. 

      Contrast resolution

    • C. 

      Interpolation

    • D. 

      Spatial resolution

  • 33. 
    The pixel size in an image using a 512 x 512  matrix and a display field of veiw of 30.2 cm is__mm
    • A. 

      0.79

    • B. 

      0.99

    • C. 

      0.39

    • D. 

      0.59

  • 34. 
    What are the purpose of filters within the xray tube of a ct scanner
    • A. 

      To decrease the scan time

    • B. 

      To remove high energy photons from the beam

    • C. 

      To remove low energy xray photons from the beam

    • D. 

      To increase patient dose

  • 35. 
    In helical ct scanning , a pitch of 1 results in ________bands of data
    • A. 

      Fewer

    • B. 

      Overlapping

    • C. 

      Adjacent

    • D. 

      More

  • 36. 
    Which of the following is a characteristic of 3rd generation ct scanners
    • A. 

      The detectors are arranged in linear configuration

    • B. 

      The xray tube and detectors rotate continuously in a 360 degree arc

    • C. 

      The scanner uses a side to side motion called translation

    • D. 

      The assembly is stopepd and rotated between each scan

  • 37. 
    The way the xray beam passes through the patient and is aquired by the ct detectors is calledbeam
    • A. 

      Geometry

    • B. 

      Speed

    • C. 

      Transmission

    • D. 

      Projection

  • 38. 
    Which ct scanners were designed for cardiac imaging specifically
    • A. 

      Third

    • B. 

      Fifth

    • C. 

      Fourth

    • D. 

      Second

  • 39. 
    What is another name for 6th generation ct scanners
    • A. 

      Transaxial

    • B. 

      Nutational

    • C. 

      Translational

    • D. 

      Helical

  • 40. 
    Which are the typical matrix sizes for todays ct scanners1. 512 x 5122. 120 x 1203. 1024 sx 1024
    • A. 

      1 and 2

    • B. 

      2 and 3

    • C. 

      1 and 3

    • D. 

      1, 2 and 3

  • 41. 
    What are the types of filtration used in ct1. beam shaped2. mathmatical3. projection
    • A. 

      1 and 2

    • B. 

      1,2, and 3

    • C. 

      2 and 3

    • D. 

      1. and 3

  • 42. 
    In 2nd gen. scanners , what shape wasthe xray beam
    • A. 

      Pencil

    • B. 

      Cone

    • C. 

      Fan

    • D. 

      Rectangular

  • 43. 
    Who created the first ct scanner
    • A. 

      Robert ledley

    • B. 

      Godfrey hounsfield

    • C. 

      Johan radon

    • D. 

      Allen cormack

  • 44. 
    The process by which each voxel is assigned a specific number to represent it's brightness is called
    • A. 

      Translation

    • B. 

      Specification

    • C. 

      Computation

    • D. 

      Quantization

  • 45. 
    How long should an xray tube last in a busy ct department
    • A. 

      One year

    • B. 

      6 months

    • C. 

      2 years

    • D. 

      18 months

  • 46. 
    In ct, the actual area of interest scanned is called the
    • A. 

      Region of interest

    • B. 

      Scan field of view

    • C. 

      Display field of view

    • D. 

      Matrix

  • 47. 
    Which of these components is part of the data acquisition system used in digital imaging
    • A. 

      Algorythm

    • B. 

      Analog to digital converter

    • C. 

      Picture archiving and communication system

    • D. 

      Detector

  • 48. 
    Pixel size = field of veiw  divided by _________
    • A. 

      Matrix size

    • B. 

      Scan thickness

    • C. 

      Voxel size

    • D. 

      Scan time

  • 49. 
    The detectors ability to gather the xray photons that pass through the patient is call ___________ efficiency
    • A. 

      Capture

    • B. 

      Dynamic

    • C. 

      Absorption

    • D. 

      Reproducibility

  • 50. 
    What component applies algorithyms to the attenuation data to produce the final ct image
    • A. 

      Archiving system

    • B. 

      Sample/ hold/unit

    • C. 

      Analog to digital converter

    • D. 

      Array processor

  • 51. 
    What material are most modern ct scanners made from
    • A. 

      Aluminum

    • B. 

      Carbon fiber

    • C. 

      Plastic resin

    • D. 

      Tungsten

  • 52. 
    A voxel that is equal on all sides is called
    • A. 

      Multiplanar

    • B. 

      Anisotropic

    • C. 

      Cubiform

    • D. 

      Isotropic

  • 53. 
    All generators used in ct are located inside the gantry
    • A. 

      True

    • B. 

      False

  • 54. 
    Window width adjustments influence what
    • A. 

      Blurring

    • B. 

      Contrast

    • C. 

      Patient dose

    • D. 

      Resolution

  • 55. 
    An artifact caused by a patient using several different  breath holdsat differrent levels of inspiration during scanning is called a _________ artifact
    • A. 

      Aliasing

    • B. 

      Beam hardening

    • C. 

      Misregistration

    • D. 

      Ring

  • 56. 
    Which type of linear interpolation algorythym is used in todays st scanners
    • A. 

      360 degrees

    • B. 

      180 degrees

    • C. 

      120 degrees

    • D. 

      75 degrees

  • 57. 
    A wide window width is used for exams requiring
    • A. 

      Demenstration of nearly identical densitys

    • B. 

      Few shades of gray

    • C. 

      Many shades of gray

    • D. 

      A narrow houndsfield number range

  • 58. 
    Several reconstruction methods only use 10% of the data set. which of these aplications uses 100%
    • A. 

      Shaded surface rendering

    • B. 

      Maximum intensity projections

    • C. 

      Volume rendering

    • D. 

      Curved multiplaner reconstruction

  • 59. 
    Which of the following items ensures compatibility for all modalities within the radiology department
    • A. 

      A uniform resource locator , or url

    • B. 

      The picture archiving and communication system, or pacs

    • C. 

      The digital imaging and communications in medicine standards, or dicom

    • D. 

      The hospital information system , or his

  • 60. 
    What does image smoothing do to the images
    • A. 

      Evens out bright and dark pixels to create a uniform shade of gray

    • B. 

      Removes scatter radiation from soft tissue

    • C. 

      Evens out areas that look blurred or have suble differences in gray shades

    • D. 

      Uses the middle of the anatomy as a referance point to start the field of view

  • 61. 
    When does retrospective processing occur
    • A. 

      Before the scan is performed

    • B. 

      Only after archiving

    • C. 

      After the exam is done

    • D. 

      During the exam

  • 62. 
    • A. 

      Leave only the air filled structures

    • B. 

      Enhance the darkest pixels and discard the brightest pixels

    • C. 

      Enhance the brightest pixels and discard the darkest pixels

    • D. 

      Ensure all of the anatomy is correctly within the field of view

  • 63. 
    The patient lies on the ct table parallel to the ___ axis , and perpindicular to the helical path the xray tube and detector array follow
    • A. 

      X

    • B. 

      Z

    • C. 

      Q

    • D. 

      Y

  • 64. 
    What does edge enhancement do to the image
    • A. 

      Suppresses the densest areas of anatomy

    • B. 

      Adds detail to denser anatomy in the image

    • C. 

      Delineates the needle used during ct biopsies

    • D. 

      Enhances the soft tissue anatomy

  • 65. 
    What does filterback projection do
    • A. 

      Reconstruct the images from helical to axial orientation

    • B. 

      Helps to automatically remove artifacts

    • C. 

      Doubles the amount of scan data

    • D. 

      Records the dose for the scan

  • 66. 
    S the process of interpolation do
    • A. 

      Removes the darker pixel elements, while leaving the brightest

    • B. 

      Adjusts the contour of the image by creating sharp edges from blurred ones

    • C. 

      Changes axial image into coronal, sagital or oblique images

    • D. 

      Reconstructs the spirally acquired images into what looks like indivisual slices

  • 67. 
     window level
    • A. 

      The highest boundary of the gray scale range

    • B. 

      The darkest shadeof the window width

    • C. 

      The mid point number in the hounsfield range for any given exam

    • D. 

      The equation used to determine the window width

  • 68. 
    Xenon studies are performed to
    • A. 

      To localize brain tumors

    • B. 

      To determine if there is sufficient blood flow to the brain

    • C. 

      To assess chronic headaches

    • D. 

      To provide a therapeutic alternative to surgery

  • 69. 
    The z gap algorhythm measures the
    • A. 

      Amount of radiation collected by the detector array

    • B. 

      Amount of scatter radiation from the patient

    • C. 

      Range of gray shades for a given exam

    • D. 

      Distance between 2 adjacent slices

  • 70. 
    The first cranial nerve is named ____, and its function is______check all that apply
    • A. 

      Optic

    • B. 

      Olfactory

    • C. 

      Trigeminal

    • D. 

      Sense of smell

    • E. 

      Sense of sight

    • F. 

      Sense of touch

  • 71. 
    The 2nd pair of cranial nerves arethe_______, and there function  is________check all that apply
    • A. 

      Olfactory

    • B. 

      Abducens

    • C. 

      Optic

    • D. 

      Mainly motor

    • E. 

      Sense of smell

    • F. 

      Sense of sight

  • 72. 
    The 3rd pair of cranial nerves are named___, and there function is________check all that apply
    • A. 

      Trochlear

    • B. 

      Optic

    • C. 

      Oculomotor

    • D. 

      Mainly motor, eye muscles

    • E. 

      Sense of sight

    • F. 

      Sense of touch

  • 73. 
    REDUCTION OF IMAGE BLUR IN RECONSTRUCTED CT IMAGES IS ACCOMPLISHED WITH
    • A. 

      ANALOG TO DIGITAL CONVERTER

    • B. 

      CONVOLUTION FILTERS

    • C. 

      DIGITAL TO ANALOG CONVERTER

    • D. 

      FOURIER TRANSFORMATION

  • 74. 
    Which of the following scientists were instrumental in the  initial development of ct1. alan cormack2. raymond damadian3. geodfrey hounsfield4. paul lauterbur
    • A. 

      Only 1, 2, and 3

    • B. 

      only 1 and 3

    • C. 

      Only 2 and 4

    • D. 

      Only 3

  • 75. 
    The principle advantage of ct over conventional radiography is
    • A. 

      Speed of image acquisition

    • B. 

      Energy resolution

    • C. 

      Contrast resolution

    • D. 

      sspatial resolution

  • 76. 
    Which of the following involves emission of a signal from a patient
    • A. 

      CT

    • B. 

      DIAGNOSTIC ULTRASOUND

    • C. 

      MAGNETIC RESONANCE IMAGING

    • D. 

      PROJECTION RADIOGRAPHY

  • 77. 
    WHICH OF THE FOLLOWING ARE LIMITATIONS OF CT1. SPATIAL RESOLUTION2. ARTIFACT GENERATION3. Z- AXIS RESOLUTION4. PAIENT DOSE
    • A. 

      ONLY 1. 2 AND 3

    • B. 

      ONLY 1 AND 3

    • C. 

      ONLY 2 AND 4

    • D. 

      ALL ARE CORRECT

  • 78. 
    ANOTHER TERM FOR CONVOLUTION FILTER IS
    • A. 

      BACK PROJECTION

    • B. 

      KERNEL

    • C. 

      FOURIER TRANSFORMATION

    • D. 

      LOOKUP TABLE

  • 79. 
    WHAT IS THE LIMITING SPATIAL FREQUENCY FOR A CT IMAGE WITH A PIXEL SIZE OF 1 MM
    • A. 

      5 LP/CM

    • B. 

      8 LP/CM

    • C. 

      12 LP/CM

    • D. 

      16 LP/CM

  • 80. 
    THE CENTRAL PROCESSING UNIT ( CPU ) CONTAINS WHICH OF THESE COMPONENTS1.MICROPROCESSOR2. CONTROL UNIT 3. PRIMARY MEMORY4. SECONDARY MEMORY
    • A. 

      1, 2 AND 3

    • B. 

      1 AND 3

    • C. 

      2 AND 4

    • D. 

      ALL OF THEM

  • 81. 
    A HIGH PASS CONVOLUTION FILTER WOULD MOST LIKELY BE USED TO IMAGE
    • A. 

      CARTALAGE - MUSCLE

    • B. 

      BONE- LUNG

    • C. 

      GRAY MATTER- WHITE MATTER

    • D. 

      LIVER- SPLEEN

  • 82. 
    THE HOUNSFIELD NUMBER FOR AIR IS
    • A. 

      -1000

    • B. 

      -500

    • C. 

      1000

    • D. 

      0