SPI Practice Exam Questions and Answers Plus Rationales
100% Correct (ARDMS practice tests) | Latest Update
Question 1
Which term describes blood flow changes in response to respiration?
A. Phasic
B. Parabolic
C. Spontaneous
D. Pulsatile
E. Laminar
Correct Answer: A) Phasic
Rationale: Phasic blood flow refers to changes in flow velocity that
occur in response to the respiratory cycle, often seen in venous
flow.
Question 2
What is demonstrated in this image produced by a linear array transducer
placed on a uniform tissue-mimicking phantom (assuming a visual of vertical
dropouts or lines)?
A. Time gain compensation not set properly.
B. System has low dynamic range.
C. Transducer crystals are damaged.
D. Focus control is malfunctioning.
E. Incorrect depth setting.
Correct Answer: C) Transducer crystals are damaged.
Rationale: Vertical dropouts or persistent dark lines on an image from
a linear array transducer placed on a uniform phantom are
characteristic of damaged or malfunctioning transducer elements
(crystals).
Question 3
What is dynamic aperture?
A. Aperture that varies with transmit frequency.
B. Aperture that decreases as a function of time.
,C. Aperture that increases with increasing focal length.
D. Aperture that changes as a function of frame rate.
E. Aperture that is fixed regardless of depth.
Correct Answer: C) Aperture that increases with increasing focal
length
Rationale: Dynamic aperture refers to the electronic adjustment of
the transducer's aperture size to maintain a constant beam width
(and thus consistent lateral resolution) at various depths, typically
by increasing the aperture with increasing focal length (depth).
Question 4
Which variable can cause an acoustic shadow artifact?
A. Small acoustic impedance mismatch.
B. Refraction.
C. Perpendicular incidence.
D. Low attenuation.
E. High attenuation from a strong reflector.
Correct Answer: E) High attenuation from a strong reflector.
Rationale: Acoustic shadowing occurs when a structure with very
high attenuation (e.g., bone, gallstone) blocks the sound beam,
resulting in an anechoic (dark) area posterior to the structure. The
provided incorrect option "Small acoustic impedance mismatch"
would not cause a shadow.
Question 5
What control improves the effects of attenuation?
A. Dynamic range.
B. Pulse Inversion.
C. Multiple focal zones.
D. TGC.
E. Overall gain.
Correct Answer: D) TGC
,Rationale: Time Gain Compensation (TGC) allows the sonographer to
selectively increase the amplification of echoes returning from
deeper structures, thereby compensating for the attenuation of the
ultrasound beam as it travels through tissue.
Question 6
What is the potential effect of increasing the PRF (Pulse Repetition
Frequency)?
A. Depth ambiguity.
B. Decreased frame rate.
C. Poor spatial resolution.
D. Decreased penetration.
E. Increased aliasing.
Correct Answer: D) Decreased penetration
Rationale: Increasing the PRF means pulses are sent more frequently.
To achieve this, the system must reduce the listening time, which in
turn reduces the maximum depth from which echoes can be reliably
received, thus decreasing penetration. It also increases the
potential for aliasing and depth ambiguity.
Question 7
How is lateral resolution determined for a pulse-echo system using a tissue-
mimicking test object?
A. By observing spaces between reflectors perpendicular to the beam.
B. By observing spaces between reflectors along the beam path.
C. By observing position of deepest visible reflector along the beam path.
D. By observing position of deepest visible reflector perpendicular to the
beam path.
E. By measuring the width of the beam at different depths.
Correct Answer: A) By observing spaces between reflectors
perpendicular to the beam
Rationale: Lateral resolution is the ability to distinguish two
, reflectors that are perpendicular to the ultrasound beam. Therefore,
it is determined by observing the smallest spaces between
reflectors that are oriented perpendicular to the beam path.
Question 8
According to ALARA guidelines, which parameter should be minimized?
A. Transmit power.
B. Frequency.
C. TGC.
D. Overall gain.
E. Frame rate.
Correct Answer: A) Transmit power
Rationale: The ALARA (As Low As Reasonably Achievable) principle
dictates that transmit power should be minimized to reduce patient
exposure to ultrasound energy, as it is directly related to acoustic
intensity. Other controls like TGC and overall gain can be used to
improve image brightness without increasing output.
Question 9
Which statement is most accurate regarding surface rendering 3D ultrasound
imaging?
A. Improves accuracy of volume measurement.
B. Minimizes effect of attenuation artifacts.
C. Spatial resolution improves when using a high-resolution mesh.
D. Feature-based reconstruction stores full 3D volume acquired.
E. It is primarily used for functional assessment.
Correct Answer: C) Spatial resolution improve when using high
resolution mesh
Rationale: Surface rendering focuses on displaying the external
contours of a 3D object. Spatial resolution in the rendered image
does improve with a higher resolution mesh. While 3D improves
volume accuracy, surface rendering itself doesn't directly improve it
100% Correct (ARDMS practice tests) | Latest Update
Question 1
Which term describes blood flow changes in response to respiration?
A. Phasic
B. Parabolic
C. Spontaneous
D. Pulsatile
E. Laminar
Correct Answer: A) Phasic
Rationale: Phasic blood flow refers to changes in flow velocity that
occur in response to the respiratory cycle, often seen in venous
flow.
Question 2
What is demonstrated in this image produced by a linear array transducer
placed on a uniform tissue-mimicking phantom (assuming a visual of vertical
dropouts or lines)?
A. Time gain compensation not set properly.
B. System has low dynamic range.
C. Transducer crystals are damaged.
D. Focus control is malfunctioning.
E. Incorrect depth setting.
Correct Answer: C) Transducer crystals are damaged.
Rationale: Vertical dropouts or persistent dark lines on an image from
a linear array transducer placed on a uniform phantom are
characteristic of damaged or malfunctioning transducer elements
(crystals).
Question 3
What is dynamic aperture?
A. Aperture that varies with transmit frequency.
B. Aperture that decreases as a function of time.
,C. Aperture that increases with increasing focal length.
D. Aperture that changes as a function of frame rate.
E. Aperture that is fixed regardless of depth.
Correct Answer: C) Aperture that increases with increasing focal
length
Rationale: Dynamic aperture refers to the electronic adjustment of
the transducer's aperture size to maintain a constant beam width
(and thus consistent lateral resolution) at various depths, typically
by increasing the aperture with increasing focal length (depth).
Question 4
Which variable can cause an acoustic shadow artifact?
A. Small acoustic impedance mismatch.
B. Refraction.
C. Perpendicular incidence.
D. Low attenuation.
E. High attenuation from a strong reflector.
Correct Answer: E) High attenuation from a strong reflector.
Rationale: Acoustic shadowing occurs when a structure with very
high attenuation (e.g., bone, gallstone) blocks the sound beam,
resulting in an anechoic (dark) area posterior to the structure. The
provided incorrect option "Small acoustic impedance mismatch"
would not cause a shadow.
Question 5
What control improves the effects of attenuation?
A. Dynamic range.
B. Pulse Inversion.
C. Multiple focal zones.
D. TGC.
E. Overall gain.
Correct Answer: D) TGC
,Rationale: Time Gain Compensation (TGC) allows the sonographer to
selectively increase the amplification of echoes returning from
deeper structures, thereby compensating for the attenuation of the
ultrasound beam as it travels through tissue.
Question 6
What is the potential effect of increasing the PRF (Pulse Repetition
Frequency)?
A. Depth ambiguity.
B. Decreased frame rate.
C. Poor spatial resolution.
D. Decreased penetration.
E. Increased aliasing.
Correct Answer: D) Decreased penetration
Rationale: Increasing the PRF means pulses are sent more frequently.
To achieve this, the system must reduce the listening time, which in
turn reduces the maximum depth from which echoes can be reliably
received, thus decreasing penetration. It also increases the
potential for aliasing and depth ambiguity.
Question 7
How is lateral resolution determined for a pulse-echo system using a tissue-
mimicking test object?
A. By observing spaces between reflectors perpendicular to the beam.
B. By observing spaces between reflectors along the beam path.
C. By observing position of deepest visible reflector along the beam path.
D. By observing position of deepest visible reflector perpendicular to the
beam path.
E. By measuring the width of the beam at different depths.
Correct Answer: A) By observing spaces between reflectors
perpendicular to the beam
Rationale: Lateral resolution is the ability to distinguish two
, reflectors that are perpendicular to the ultrasound beam. Therefore,
it is determined by observing the smallest spaces between
reflectors that are oriented perpendicular to the beam path.
Question 8
According to ALARA guidelines, which parameter should be minimized?
A. Transmit power.
B. Frequency.
C. TGC.
D. Overall gain.
E. Frame rate.
Correct Answer: A) Transmit power
Rationale: The ALARA (As Low As Reasonably Achievable) principle
dictates that transmit power should be minimized to reduce patient
exposure to ultrasound energy, as it is directly related to acoustic
intensity. Other controls like TGC and overall gain can be used to
improve image brightness without increasing output.
Question 9
Which statement is most accurate regarding surface rendering 3D ultrasound
imaging?
A. Improves accuracy of volume measurement.
B. Minimizes effect of attenuation artifacts.
C. Spatial resolution improves when using a high-resolution mesh.
D. Feature-based reconstruction stores full 3D volume acquired.
E. It is primarily used for functional assessment.
Correct Answer: C) Spatial resolution improve when using high
resolution mesh
Rationale: Surface rendering focuses on displaying the external
contours of a 3D object. Spatial resolution in the rendered image
does improve with a higher resolution mesh. While 3D improves
volume accuracy, surface rendering itself doesn't directly improve it
