Ultrasonography-physics-1
Quiz to test your basic definion, concept and knowldge. It will increase your score by 20-50% in 2--4 weeks.
- 1.
The edge shadowing occurs in which of following situations
- A.
Small interfaces
- B.
Large interfaces
- C.
Curved interfaces
- D.
Smooth interfaces
Correct Answer
C. Curved interfaces -
- 2.
A large, smooth interface is usually called
- A.
Specular reflector
- B.
Impedance
- C.
Absorption
- D.
Scattering
Correct Answer
A. Specular reflector -
- 3.
What system control can you adjust to compensate for the effect of sound attenuation in the body
- A.
Dynamic range
- B.
TGC
- C.
Frame averaging
- D.
Depth
- E.
Line density
Correct Answer
B. TGC -
- 4.
Which of the following interation of sound and tissue decreases the intensity of the transmitted beam
- A.
Absorption
- B.
Reflection
- C.
Scattering
- D.
Conversion of sound to heat
- E.
All of the above
Correct Answer
E. All of the above -
- 5.
An another term for nonspecular reflection is
- A.
Destructive interference
- B.
Refraction
- C.
Diffraction
- D.
Scattering
- E.
Attenuation
Correct Answer
D. Scattering -
- 6.
Which of the following will not cause a redirection of part of the ultrasound energy?
- A.
Reflection
- B.
Scattering
- C.
Divergence
- D.
Absorption
- E.
Refraction
Correct Answer
D. Absorption -
- 7.
Which of the following are you most likely to encounter when you scan a large fat mass
- A.
Posterior acoustic shadowing caused by increased attenuation through fat
- B.
Axial misregistration of objects distal to the mass on the screen caused by the slower propagation speed through fat
- C.
Lateral misregistration of the mass on the screen because of refraction
- D.
Total reflection of the sound beam caused by a large acoustic impedance mismatch
- E.
Diffraction of the sound beam due to a virtual small aperture through the mass
Correct Answer
B. Axial misregistration of objects distal to the mass on the screen caused by the slower propagation speed through fat -
- 8.
When the sound beam is refracted during a sonographic examination, which of the following might you detect on the ultrasound image?
- A.
Axial misregistration
- B.
Lateral misregistration
- C.
Reverberations osterior to a reflector
- D.
Enchancement of a reflector
- E.
Electrical interference
Correct Answer
B. Lateral misregistration -
- 9.
What interaction of ultrasound and tissue is primarily responsible for imaging the internal structure of organs?
- A.
Scattering
- B.
Specular reflection
- C.
Refraction
- D.
Diffraction
- E.
Destructive interference
Correct Answer
A. Scattering -
- 10.
If the number of cycles in a pulse is increased but the wavelength remains the same, which of the following is true?
- A.
The frequency is increased
- B.
The propagation speed is increased
- C.
The pulse duration is increased
- D.
The period is increased
- E.
The bulk modulus is decreased
Correct Answer
C. The pulse duration is increased -
- 11.
True or False The frequency and wavelength of a sound will change when it propagates through tissue.
- A.
True
- B.
False
Correct Answer
A. True -
- 12.
Bandwidth refers to:
- A.
Number of cycles per pulse
- B.
Range of frequencies in a pulse
- C.
Rate of pulse repetition frequency
- D.
Range of pulse in a frame
- E.
Number of wavelengths in one second
Correct Answer
B. Range of frequencies in a pulse -
- 13.
Interference patterns of reflected waves causes
- A.
Acoustic speckle
- B.
Acoustic enhancement
- C.
Rarefaction
- D.
Volume averaging
- E.
All of above
Correct Answer
A. Acoustic speckle -
- 14.
The impedance of a transducer active element is 1,900,000 rays, and the impedance of the skin is 1,400,000 rays. What is an acceptable impedance for the matching layer?
- A.
1,200,000 Rays
- B.
1,400,000 Rays
- C.
1,726,000 Rays
- D.
1,950,000 Rays
Correct Answer
C. 1,726,000 RaysExplanation
thhhhe impedance of the matching layser is between that of the active element and the skin.Rate this question:
-
- 15.
Which of the following crystals will produce sound with the lowest frequency?
- A.
Thin and with a low speed
- B.
Thin and with a high speed
- C.
Thick and a low speed
- D.
Thick and with a speed
Correct Answer
C. Thick and a low speedExplanation
Sound with the lowes frequency is produced by a thick active element in which sound travels slowly.Rate this question:
-
- 16.
True or FalseImaging transducers are usually of high rather than low bandwidth.
- A.
True
- B.
False
Correct Answer
A. True -
- 17.
True or False?A pulse with a long pulse duration is likely to have a narrow badwidth?
- A.
True
- B.
False
Correct Answer
A. TrueExplanation
True. Longer events tend to have narrow badwidth. Shorter events tend to have wider bandwidth.Rate this question:
-
- 18.
True or FalseThe spatial pulse length usually decrease when operating frequency is changed to high
- A.
True
- B.
False
Correct Answer
A. TrueExplanation
Spatial pulse length is wavelength times cycles in a pulse. when frequency increase, wavelength decrease. So the spatial pulse length also decrease.Rate this question:
-
- 19.
True or FalseAxial resolution is improved in the focal zone.
- A.
True
- B.
False
Correct Answer
B. FalseExplanation
Axial resolution has nothing to with focal zone. Axial resolution depend on Spatial pulse length.
Axial resolution=SPL/2.Rate this question:
-
- 20.
True or False?Lateral resolution is decided by the beam diameter.
- A.
True
- B.
False
Correct Answer
A. True -
- 21.
True or False?Lateral resolution improves with frequency.
- A.
True
- B.
False
Correct Answer
B. FalseExplanation
Lateral resolution is decidied by diameter of sound beam. Axial resolution rely on frequency, wavelength, SPL and PD.Rate this question:
-
- 22.
True or False?Grating lobes are essential for the proper operation of a linear phased array.
- A.
True
- B.
False
Correct Answer
B. FalseExplanation
Grating lobes are an undesireable property of multi-element array transducers.Rate this question:
-
- 23.
True or False?Electronically steered scanners always produce higher resolution images thant do mechanically steered scanners.
- A.
True
- B.
False
Correct Answer
B. FalseExplanation
resolution is decided by characteristics of scanner such as frequency, wavelenth, spl not by scanner configuration.Rate this question:
-
- 24.
The number of frames per second necessary for a real-time image to be flicker free is
- A.
More than 15
- B.
Less than 10
- C.
Between 6 and 10
- D.
Between 3 and 6
Correct Answer
A. More than 15 -
- 25.
True or False?The SPTA intensity will always be larger than the SATA intensity.
- A.
True
- B.
False
Correct Answer
A. True -
- 26.
True or False?The intensity of the ultrasound beam is increased by 4 times if the amplitude is doubled.
- A.
True
- B.
False
Correct Answer
A. TrueExplanation
Intensity is the square of the amplititude.Rate this question:
-
- 27.
True or False?In a pulse-echo system, the quality factor should be made as large as possible.
- A.
True
- B.
False
Correct Answer
B. FalseExplanation
The Q factor or quality factor of a transducer refers to the length of time that the sounds persists. High Q transducers tend to ring for long time and provide poor imagesRate this question:
-
- 28.
The transducer that would be best suited for intercostal scanning is
- A.
Linear-sequenced array real-time
- B.
Mechanical sector real-time transducer
- C.
Static with with large diameter
- D.
No type of transducer can scan between the intercostal space
Correct Answer
B. Mechanical sector real-time transducerExplanation
A real-time mechanical sector transducer allows greater maneuverablity for small intercostal space scanning.Rate this question:
-
- 29.
The normal range of wave length in medical application is
- A.
0.1-1.5 mm
- B.
1.5-2mm
- C.
2-5mm
- D.
5.5-15mm
Correct Answer
A. 0.1-1.5 mm -
- 30.
Which of the following combinations of frequency and intensity would most likely result in cavitaion?
- A.
High frequency and low intensity
- B.
Low frequency and high intensity
- C.
High frequency and high intensity
- D.
Intensity has no effect on cavitation
Correct Answer
B. Low frequency and high intensityExplanation
A combination of low frequency and high intensity is most likely to cause cavitation resulting in tissue damage.Rate this question:
-
- 31.
What is distinction between real-time scans and B-scans?
- A.
No distinction; real-time scans are B-scans
- B.
Real-time scans display gray-scale scans; whereas, b-scans display bistable images
- C.
Real time scans exhibit static images; whereas, B-scans exhibit static images
- D.
B-scans are specific for static scanners; real-time scans are not.
Correct Answer
A. No distinction; real-time scans are B-scansExplanation
No distinction. All real-time scans B-scans, and both static and real-time instruments employ B-mode.Rate this question:
-
- 32.
Which of the following is not a component of the time-gain compensation (TGC) curve?
- A.
Grey scale
- B.
Far gain
- C.
Knee
- D.
Delay
Correct Answer
A. Grey scaleExplanation
The TGC is commprised of near gan,delay,slope,knee, and far gain.Rate this question:
-
- 33.
The range of pulse repetition frequencies used in diagnostic ultrasound is
- A.
0.5-4 kHz
- B.
1-10 MHz
- C.
1-7 kHz
- D.
10-15 MHz
Correct Answer
A. 0.5-4 kHz -
- 34.
True or FalseA videotape recorder records at a rate of 30 frames/s and therefore cannot be used to record images from a mechanical scanner operating a lower frame rates
- A.
True
- B.
False
Correct Answer
B. FalseExplanation
False. In many cases, electronic and mechanical canners demonstrate a frame rate lower than 30 frames/s.Rate this question:
-
- 35.
Beam steering is achieved in a linear phase array by
- A.
Mechanical motion
- B.
Electronic time-delay pulsing
- C.
An acoustic lens
- D.
Dynamic focusing
Correct Answer
B. Electronic time-delay pulsingExplanation
The delay pulsing of the array elements can be used to form a wave-front directed at different angles. Pulsing can also be used to focus the beam at different depths.Rate this question:
-
- 36.
Which of the following is true?
- A.
SPTA is always equal to or greater than SPTP
- B.
SPTP is always equal to or greater than SPTA
- C.
SATA is always equal to or greater than SATP
- D.
SPTA is always equal to or greater than SATP
Correct Answer
B. SPTP is always equal to or greater than SPTAExplanation
In All cases, peak values will be at least as great as the averages values by definition. In continuous wave ultrasound, there is no variation of intensity in time, and peak values will be equal.Rate this question:
-
- 37.
A transducer with a large bandwidth is likely to have
- A.
Good axial resolution
- B.
A large ring-down time
- C.
Poor resolution
- D.
A high Q factor
Correct Answer
A. Good axial resolutionExplanation
a large bandwidth is equivalent to a short spatial pulse lengthRate this question:
-
- 38.
An annular array real-time scanner
- A.
Is steered electronically
- B.
Is steered mechanically
- C.
Is not capable of electronic focusing
- D.
Is not used with digital-scan converters
Correct Answer
B. Is steered mechanically -
- 39.
True or False?The transducer produces more than one frequency. The shorter the pulse, the more of these spectrum of other frequencies are also produced.
- A.
True
- B.
False
Correct Answer
A. True -
- 40.
True or False?Mechanical transducers are mechanically steered (MS) and mechanically focused (MS).
- A.
True
- B.
False
Correct Answer
A. True -
- 41.
True or False?The synchronous signal processing uses a Doppler carrier frequency that is the same as the imaging center operating frequency
- A.
True
- B.
False
Correct Answer
A. TrueExplanation
True. Because synchronous signal processing uses the same echo signal for both Doppler and gray-scale signal processing, the frequency ust be the same.Rate this question:
-
- 42.
True or False?A measurement of the peak systolic frequency in a carotid artery with a single-point spectrum will be lower than a measurement of the color-encoded frequency at the same point.
- A.
True
- B.
False
Correct Answer
B. FalseExplanation
false. Because color uses the average frequency at each location, the maximum systolic frequency will always be greater than the mean value.Rate this question:
-
- 43.
Changes in the Doppler shift frequencies within a color flow image sample site appear in the image as
- A.
Nothing; the image only shows changes in phase
- B.
Different colors(hues)
- C.
Different levels of color saturation (purity)
- D.
Different colors (hues) or different levels of saturation (purity)
Correct Answer
D. Different colors (hues) or different levels of saturation (purity)Explanation
The average frequency within each Doppler sample site is portrayed as a change in either color saturation (purity or whiteness) or hue (color). the object is to use the color to show flow patterns within the vessel lumen or heart chambers.Rate this question:
-
- 44.
One begins reading a color flow image by
- A.
Determining the maximum systolic frequency
- B.
Knowing the position of position of the scan plane on the patient's body
- C.
Knowing the direction of flow relative to the transducer
- D.
Determining the Doppler carrier frequency
Correct Answer
B. Knowing the position of position of the scan plane on the patient's bodyExplanation
The expected flow pattern in any vessel comes from knowing how the scan plane is positioned on the patient, For example, the patient's head is always placed on the image left in long axis scans, and the patients's patient side is always on the image left in cross-sectional scans.Rate this question:
-
- 45.
True or False?The shape of the sample volume in pulsed Doppler has a major effect on the content of the Doppler signal.
- A.
True
- B.
False
Correct Answer
A. TrueExplanation
True. The sample volume and flow interact in a manner that depends on the geometry of the sample volume.Rate this question:
-
- 46.
Power Doppler imaging is a good choice when you
- A.
Want to show tissue perfusion
- B.
Want to show tissue velocity
- C.
Want to easily separate blood flow form simple tissue otion
- D.
A and B
Correct Answer
A. Want to show tissue perfusion -
- 47.
Turbulence in a vascular color flow image appears as
- A.
A mottled pattern of colors
- B.
A mottled pattern of read and blue with changing saturations
- C.
A mottled green region
- D.
A or B
Correct Answer
D. A or BExplanation
In vascular color flow imaging, turbulence appears as broken streamlines. The image then takes on a mottled appearance either in color or in color saturation.Rate this question:
-
- 48.
True or False?The color coding of red arteries and blue veins and the slow high-resolution frame rates make the identity of arteries and veins in the abdomen direct and easy.
- A.
True
- B.
False
Correct Answer
B. FalseExplanation
The large fields of view for abdominal imaging slow the framrate. In addition, vessel anatomy goes in all directions. Sorting out arteries and veins requires the spectrum to determine pulsatility.Rate this question:
-
- 49.
True or False?Increasing a sonograph's output power levels and PRF to increase penetration and frame rate can produce an artifact of high-frequency aliasing.
- A.
True
- B.
False
Correct Answer
B. FalseExplanation
High PRF and high output power permit structures from out-side the field of view to enter the image as a range ambiguity artifact.Rate this question:
-
- 50.
Both the color and a point spectrum in a stenosis show high-frequency aliasing, one strategy for removing the aliasing involes
- A.
Doing nothing,. Aliasing cannot be removed from the system
- B.
Decreasing the system PRF
- C.
Decreasing the carrier frequency
- D.
Decreasing the Doppler angle toward zero
Correct Answer
C. Decreasing the carrier frequencyExplanation
Decreasing the carrier frequency moves all Doppler frequencies downward and may bring the high aliasing frequencies below the aliasing limit.Rate this question:
-
Quiz Review Timeline +
Our quizzes are rigorously reviewed, monitored and continuously updated by our expert board to maintain accuracy, relevance, and timeliness.
-
Current Version
-
Mar 21, 2022Quiz Edited by
ProProfs Editorial Team -
Jan 17, 2010Quiz Created by
Taofu2009la
Back to top