DAVIES SPI REVIEW STUDY GUIDE 2026
COMPREHENSIVE QUESTION–ANSWER
DIGEST
◉ The thermal index indicates:
Answer: Estimated temperature increase in tissue
◉ You are performing a sonographic exam and notice that the TI
reading is 1. What does this indicate?
Answer: The output level is high enough that the temperature could
increase as much as 1 degree Celsius if the transducer were held
stationary
◉ A shadow depicted by a renal stone is primarily a result of the
following sound-tissue interaction:
Answer: Reflection
◉ If sound waves of 3MHz, 5MHz, and 10MHz are transmitted
through the same section of anatomy, reflections from which
frequency would reach the transducer first?
Answer: Reflections from all 3 frequencies would have nearly
identical transmit times
,◉ What type of sound travels through a vacuum?
Answer: Sound cannot travel through a vacuum
◉ The maximum cyclical change in a quantity is known as:
Answer: Amplitude
◉ Two benefits of tissue harmonic imaging:
Answer: Grating lobe artifacts are reduced and lateral resolution is
improved
◉ Wavelength depends on what two factors:
Answer: Propagation speed and frequency
◉ What sound parameter is determined only by the medium?
Answer: Propagation speed
◉ Snell's Law describes:
Answer: The angle of sound transmission at an interface between
media having different propagation speeds
◉ What sonographic application has the lowest FDA approved SPTA
values?
,Answer: Ophthalmic
◉ Which of the following human tissues has the highest rate of
attenuation of an ultrasound wave?
Answer: Lung
◉ What can you improve by changing the grayscale map?
Answer: Contrast resolution
◉ What describes an analog signal?
Answer: CONTINUOUS variation of the signal is possible
◉ What system control converts the numbers stored in memory to
proportional voltages that control the brightness on a CRT monitor?
Answer: Digital to Analog converter
◉ What physical concept allows us to determine the location of an
interface by measuring the elapsed time between the transmitted
pulsed ultrasound wave and the detected echo from that interface?
Answer: Echo RANGING
◉ When adjusting the PRF you are changing what?
Answer: The number of pulses per second
, ◉ Which artifact is related to the sound beam traveling through a
structure with low attenuation?
Answer: Enhancement
Enhancement occurs distal to a structure that has less attenuation of
the sound beam compared to the surrounding tissue. Hence, there is
more
signal beyond it and the reflections have greater amplitude, resulting
in a brighter image.
◉ What part of the color map represents the highest POSITIVE
doppler shift?
Answer: The color(s) at the very top of the color map
◉ When you increase the scan line density in the B-mode image, you
improve:
Answer: Lateral resolution
Lateral resolution decreases when the distance between vectors
(lines of sight) is greater than the beam width.
COMPREHENSIVE QUESTION–ANSWER
DIGEST
◉ The thermal index indicates:
Answer: Estimated temperature increase in tissue
◉ You are performing a sonographic exam and notice that the TI
reading is 1. What does this indicate?
Answer: The output level is high enough that the temperature could
increase as much as 1 degree Celsius if the transducer were held
stationary
◉ A shadow depicted by a renal stone is primarily a result of the
following sound-tissue interaction:
Answer: Reflection
◉ If sound waves of 3MHz, 5MHz, and 10MHz are transmitted
through the same section of anatomy, reflections from which
frequency would reach the transducer first?
Answer: Reflections from all 3 frequencies would have nearly
identical transmit times
,◉ What type of sound travels through a vacuum?
Answer: Sound cannot travel through a vacuum
◉ The maximum cyclical change in a quantity is known as:
Answer: Amplitude
◉ Two benefits of tissue harmonic imaging:
Answer: Grating lobe artifacts are reduced and lateral resolution is
improved
◉ Wavelength depends on what two factors:
Answer: Propagation speed and frequency
◉ What sound parameter is determined only by the medium?
Answer: Propagation speed
◉ Snell's Law describes:
Answer: The angle of sound transmission at an interface between
media having different propagation speeds
◉ What sonographic application has the lowest FDA approved SPTA
values?
,Answer: Ophthalmic
◉ Which of the following human tissues has the highest rate of
attenuation of an ultrasound wave?
Answer: Lung
◉ What can you improve by changing the grayscale map?
Answer: Contrast resolution
◉ What describes an analog signal?
Answer: CONTINUOUS variation of the signal is possible
◉ What system control converts the numbers stored in memory to
proportional voltages that control the brightness on a CRT monitor?
Answer: Digital to Analog converter
◉ What physical concept allows us to determine the location of an
interface by measuring the elapsed time between the transmitted
pulsed ultrasound wave and the detected echo from that interface?
Answer: Echo RANGING
◉ When adjusting the PRF you are changing what?
Answer: The number of pulses per second
, ◉ Which artifact is related to the sound beam traveling through a
structure with low attenuation?
Answer: Enhancement
Enhancement occurs distal to a structure that has less attenuation of
the sound beam compared to the surrounding tissue. Hence, there is
more
signal beyond it and the reflections have greater amplitude, resulting
in a brighter image.
◉ What part of the color map represents the highest POSITIVE
doppler shift?
Answer: The color(s) at the very top of the color map
◉ When you increase the scan line density in the B-mode image, you
improve:
Answer: Lateral resolution
Lateral resolution decreases when the distance between vectors
(lines of sight) is greater than the beam width.
