DAVIES SPI: IV. PULSE-ECHO INSTRUMENTATION (30%
OF ARDMS) 2025 EXAM WITH ANSWERS.
Which action would decrease frame rate?
A. Increasing pulse repetition frequency
B. Increasing acoustic scan line density
C. Decreasing sector width
D. Decreasing the number of focal zones
E. Decreasing image depth -correct answer -B. Increasing
acoustic scan line density
<Temporal resolution is determined by the frame rate. Several factors
affect the frame rate. As the density of the acoustic scan lines increases,
lateral resolution increases, but frame rate decreases because it takes
additional time to perform the pulse- listen sequences for each new line of
sight. All of the other answer choices would result in increased temporal
resolution (increased frame rate>
You have expanded the image sector width to improve visualization of a
large mass. What can you do to maintain the same temporal resolution you
had before your adjustment?
A. Increase the digitization bit depth
B. Increase the number of scan lines
C. Decrease the number of pixels in the image matrix
,D. Decrease the number of focal zones
E. Decrease the pulse repetition frequency -correct answer -D.
Decrease the number of focal zones
<On each line of sight, a pulse-echo sequence is required for each focal
zone selected. Therefore, as the number of focal zones increases, the frame
rate decreases>
A standard for handling and transferring images and medical information
between computers is:
A. Voxel
B. DICOM
C. HIPAA
D. VPN
E. Worklist -correct answer -B. DICOM
<DICOM stands for Digital Imaging and Communications in Medicine>
Which of the following artifacts commonly results in echoes filling in the
lumina of small vessels?
A. Refraction
B. Partial volume
C. Mirror image
D. Range ambiguity
,E. Multipath reflections -correct answer -B. Partial volume
Propagation speed error results in which sonographic appearance?
A. Improper lateral position of an echo
B. Improper axial position of an echo
C. Shadowing behind an echo
D. Enhancement behind an echo
E. None of the above -correct answer -B. Improper axial position of an
echo
<If the propagation speed through a mass differs significantly from that of
surrounding tissue, improper axial position of the mass will occur. Why?
The ultrasound system is set up to assume that the speed of sound is
constant at 1540 m/s. If it is much slower than this, it will take longer for
the ultrasound to travel round trip to and from a reflector, and the
reflections will be placed deeper in the image. Conversely, if the
propagation speed through a mass is significantly faster than that of
surrounding tissue, the round-trip travel time will be reduced, and the
reflections will be placed more shallowly in the image.
Answer choice A would be correct only in the case of refraction, which
requires propagation speed difference and oblique incidence. The term
propagation speed error does not apply to this phenomenon, however.
Answer B is therefore the best andcorrect answer>
When you select one focal zone, how many pulse/listen cycles are required
for each acoustic scan line in one image frame?
, A. One
B. Two
C. Four
D. Eight
E. Sixteen -correct answer -A. One
What type of resolution is determined by the number of pixels in the scan
converter?
A. Temporal
B. Contrast
C. Spatial
D. Elevational
E. All of the above -correct answer -C. Spatial
<As the number of pixels increases, the spatial resolution of the image
improves. The spatial resolution can be no better than that obtained from the
beam forming, but it can be worse>
Pulsing of a transmitted sound wave is necessary for real-time imaging because:
A. The transducer becomes too hot to handle if continuous sound waves
are emitted
B. The crystal in the transducer will break under the stress of
OF ARDMS) 2025 EXAM WITH ANSWERS.
Which action would decrease frame rate?
A. Increasing pulse repetition frequency
B. Increasing acoustic scan line density
C. Decreasing sector width
D. Decreasing the number of focal zones
E. Decreasing image depth -correct answer -B. Increasing
acoustic scan line density
<Temporal resolution is determined by the frame rate. Several factors
affect the frame rate. As the density of the acoustic scan lines increases,
lateral resolution increases, but frame rate decreases because it takes
additional time to perform the pulse- listen sequences for each new line of
sight. All of the other answer choices would result in increased temporal
resolution (increased frame rate>
You have expanded the image sector width to improve visualization of a
large mass. What can you do to maintain the same temporal resolution you
had before your adjustment?
A. Increase the digitization bit depth
B. Increase the number of scan lines
C. Decrease the number of pixels in the image matrix
,D. Decrease the number of focal zones
E. Decrease the pulse repetition frequency -correct answer -D.
Decrease the number of focal zones
<On each line of sight, a pulse-echo sequence is required for each focal
zone selected. Therefore, as the number of focal zones increases, the frame
rate decreases>
A standard for handling and transferring images and medical information
between computers is:
A. Voxel
B. DICOM
C. HIPAA
D. VPN
E. Worklist -correct answer -B. DICOM
<DICOM stands for Digital Imaging and Communications in Medicine>
Which of the following artifacts commonly results in echoes filling in the
lumina of small vessels?
A. Refraction
B. Partial volume
C. Mirror image
D. Range ambiguity
,E. Multipath reflections -correct answer -B. Partial volume
Propagation speed error results in which sonographic appearance?
A. Improper lateral position of an echo
B. Improper axial position of an echo
C. Shadowing behind an echo
D. Enhancement behind an echo
E. None of the above -correct answer -B. Improper axial position of an
echo
<If the propagation speed through a mass differs significantly from that of
surrounding tissue, improper axial position of the mass will occur. Why?
The ultrasound system is set up to assume that the speed of sound is
constant at 1540 m/s. If it is much slower than this, it will take longer for
the ultrasound to travel round trip to and from a reflector, and the
reflections will be placed deeper in the image. Conversely, if the
propagation speed through a mass is significantly faster than that of
surrounding tissue, the round-trip travel time will be reduced, and the
reflections will be placed more shallowly in the image.
Answer choice A would be correct only in the case of refraction, which
requires propagation speed difference and oblique incidence. The term
propagation speed error does not apply to this phenomenon, however.
Answer B is therefore the best andcorrect answer>
When you select one focal zone, how many pulse/listen cycles are required
for each acoustic scan line in one image frame?
, A. One
B. Two
C. Four
D. Eight
E. Sixteen -correct answer -A. One
What type of resolution is determined by the number of pixels in the scan
converter?
A. Temporal
B. Contrast
C. Spatial
D. Elevational
E. All of the above -correct answer -C. Spatial
<As the number of pixels increases, the spatial resolution of the image
improves. The spatial resolution can be no better than that obtained from the
beam forming, but it can be worse>
Pulsing of a transmitted sound wave is necessary for real-time imaging because:
A. The transducer becomes too hot to handle if continuous sound waves
are emitted
B. The crystal in the transducer will break under the stress of
