SPI Exam Questions And Answers: Lateral
Resolution and Focusing
The focus of an ultrasound beam is the location where the ____.
A. beam is the broadest
B. optimum transverse resolution is
C. frequency is the highest
D. finest depth resolution is obtained -
correct answer ✅B. The focus of an ultrasound beam is the
location where the beam is most narrow. The narrowest portion of
the beam provides the optimal transverse or lateral resolution.
The lateral resolution of an ultrasound system is primarily
determined by the ____.
A. width of the sound pulse
B. length of the ultrasound pulse
C. duration of the sound pulse
D. none of the above -
correct answer ✅A. The lateral resolution achieved by an imaging
system is approximately equal to the width of the ultrasound pulse.
Two ultrasound systems produce acoustic pulses. One pulse is 0.4
usec in duration and the other is 0.2 usec. Which pulse will most
likely provide the best lateral resolution?
, SPI Exam Questions And Answers: Lateral
Resolution and Focusing
A) 0.4 usec pulse
B) 0.2 usec pulse
C) they are the same
D) cannot be determined -
correct answer ✅D. The duration of a pulse is unrelated to the
lateral resolution. PD affects axial (longitudinal) resolution. It is not
possible to answer the question with the information provided.
T/F: The PD does not profoundly influence the lateral resolution. -
correct answer ✅TRUE. Generally, the primary determinant of
lateral resolution is the sound beam's diameter. The pulse length,
or duration, does not dramatically alter the lateral resolution.
Two ultrasound systems have NZLs of 8 cm. At the focus, System G's
lateral resolution is 3.0 mm, whereas System P's is 5.0 mm. Which
system will produce higher quality pictures at their foci?
A. System P
B. System G
C. both will be of similar quality -
correct answer ✅B. Since System G has a narrower beam than
System P at the end of the near field (which is the location of the
foci), System G will produce higher quality images at that depth.
Resolution and Focusing
The focus of an ultrasound beam is the location where the ____.
A. beam is the broadest
B. optimum transverse resolution is
C. frequency is the highest
D. finest depth resolution is obtained -
correct answer ✅B. The focus of an ultrasound beam is the
location where the beam is most narrow. The narrowest portion of
the beam provides the optimal transverse or lateral resolution.
The lateral resolution of an ultrasound system is primarily
determined by the ____.
A. width of the sound pulse
B. length of the ultrasound pulse
C. duration of the sound pulse
D. none of the above -
correct answer ✅A. The lateral resolution achieved by an imaging
system is approximately equal to the width of the ultrasound pulse.
Two ultrasound systems produce acoustic pulses. One pulse is 0.4
usec in duration and the other is 0.2 usec. Which pulse will most
likely provide the best lateral resolution?
, SPI Exam Questions And Answers: Lateral
Resolution and Focusing
A) 0.4 usec pulse
B) 0.2 usec pulse
C) they are the same
D) cannot be determined -
correct answer ✅D. The duration of a pulse is unrelated to the
lateral resolution. PD affects axial (longitudinal) resolution. It is not
possible to answer the question with the information provided.
T/F: The PD does not profoundly influence the lateral resolution. -
correct answer ✅TRUE. Generally, the primary determinant of
lateral resolution is the sound beam's diameter. The pulse length,
or duration, does not dramatically alter the lateral resolution.
Two ultrasound systems have NZLs of 8 cm. At the focus, System G's
lateral resolution is 3.0 mm, whereas System P's is 5.0 mm. Which
system will produce higher quality pictures at their foci?
A. System P
B. System G
C. both will be of similar quality -
correct answer ✅B. Since System G has a narrower beam than
System P at the end of the near field (which is the location of the
foci), System G will produce higher quality images at that depth.
