ARDMS SPI EXAM LATEST 2024-2025
Example of nonspecular reflector - (correct Answer) - red blood cells
What happens to spatial pulse length when frequency increases? - (correct Answer) - decreases
Axial resolution is dependent on? - (correct Answer) - wavelength
Lateral resolution is dependent on? - (correct Answer) - beam diameter
Where does the beam of an unfocused transducer diverge? - (correct Answer) - Fraunhofer zone
Reverberation artifacts are a result of - (correct Answer) - two or more strong reflecting surfaces
True/False: Grating lobes are essential for the proper operation of a linear phased array. - (correct Answer) -
False
True/False: Electronically steered scanners always produce higher resolution images than do mechanically
steered scanners. - (correct Answer) - False
True/False: An annular array scanner uses mechanical beam steering. - (correct Answer) - True
True/False: A linear sequenced array cannot be dynamically focused. - (correct Answer) - False
registration or B-mode alignment - (correct Answer) - Which AIUM test object function utilizes all the groups of
wires in the AIUM 100 mm test object?
axial resolution - (correct Answer) - Which AIUM test object function utilizes the A group of wires in the AIUM
100 mm test object?
lateral resolution - (correct Answer) - Which AIUM test object function utilizes the B group of wires in the AIUM
100 mm test object?
dead zone - (correct Answer) - Which AIUM test object function utilizes the D group of wires in the AIUM 100
mm test object?
depth calibration - (correct Answer) - Which AIUM test object function utilizes the C or E groups of wires in the
AIUM 100 mm test object?
What happens to axial resolution when spatial pulse length is decreased? - (correct Answer) - improves
How much will a 3.5 MHz pulse be attenuated after passing through 2 cm of soft tissue? - (correct Answer) - 3.5
dB
Propagation speed errors result in - (correct Answer) - improper axial position
Enhancement is caused by - (correct Answer) - weakly attenuating structures
The Doppler shift frequency is - (correct Answer) - directly proportional to the velocity of the reflector
,The number of frames per second necessary for a real-time image to be flicker free is - (correct Answer) - more
than 15
True/False: The SPTA intensity will always be larger than the SATA intensity. - (correct Answer) - True
The intensity of the ultrasound beam is usually greater at the focal zone because of - (correct Answer) - the
smaller beam diameter
If the amplitude is doubled, the intensity is - (correct Answer) - quadrupled
The attenuation for soft tissue is - (correct Answer) - increased with tissue thickness
The acoustic impedance of the matching layer - (correct Answer) - can be chosen to improve transmission into
the body
True/False: In a pulse-echo system, the quality factor should be made as large as possible. - (correct Answer) -
False
True/False: The beam diameter is constant in the near zone. - (correct Answer) - False
The operating frequency is dependent on - (correct Answer) - thickness of the crystal
The period of an ultrasound wave is - (correct Answer) - the time of one wavelength
The dynamic range of a system is - (correct Answer) - the ratio of smallest to largest power level that the
system can handle
True/False: The intensity of an ultrasonic beam can be measured with radiation force balance. - (correct
Answer) - True
Increasing the pulse repetition period - (correct Answer) - increases the maximum depth that can be imaged
Ultrasound bioeffects - (correct Answer) - are not confirmed below 100 mW/cm² SPTA
True/False: No refraction can occur at an interface if the media impedances are equal. - (correct Answer) -
False
True/False: Smaller transducers always produce smaller beam diameters. - (correct Answer) - False
True/False: The ultrasound beam profile can be measured with a hydrophone. - (correct Answer) - True
True/False: The pulsed-Doppler system yields better depth resolution than the continuous wave (CW) system. -
(correct Answer) - True
True/False: The gray-scale display was made possible when digital scan converters replaced analog scan
converters. - (correct Answer) - False
True/False: Videotape recorders operating at 30 frames per second cannot be used with mechanical real-time
units because the fram rate is too slow. - (correct Answer) - False
True/False: Linear phased array scanners need no form of mechanical focusing because focusing is performed
,electronically. - (correct Answer) - False
True/False: The fram rate of real-time scanners depends on the number of lines used to form the image. -
(correct Answer) - True
True/False: It is not possible to steer an annular phased array electronically. - (correct Answer) - True
True/False: The near zone length should be kept as short as possible. - (correct Answer) - False
What percentage of intensity of an ultrasound pulse incident on an interface of 0.25 and 0.75 rayls is reflected?
- (correct Answer) - 25%
Axial resolution can be improved by using - (correct Answer) - higher frequency transducers
When particle motion of a medium is parallel to the direction of a wave propagation, the wave being
transmitted is called a - (correct Answer) - longitudinal wave
The wavelength in a material having a wave velocity of 1500 m/s emplying a transducer frequency of 5 MHz is -
(correct Answer) - 0.3 mm
The factor that determines the amount of reflection at the interface of two dissimilar materials is - (correct
Answer) - difference in acoustic impedances
The equation that describes the relationship among propagation, wavelength, and frequency is - (correct
Answer) - λ = c/ƒ
What three things can occur when an ultrasonic beam reaches the interface of two dissimilar materials? -
(correct Answer) - reflection, refraction, mode conversion
The acoustic impedance of a material is - (correct Answer) - equal to the product of density and velocity
The average velocity of ultrasonic waves in soft tissue is - (correct Answer) - 1540 m/s
True/False: Receiver-angle values in CW Doppler analysis do not influence the final Doppler shift. - (correct
Answer) - False
Refraction occurs because of difference in ______ across an interface between two materials - (correct Answer)
- wave velocity
Reflection factor at an interface between two materials depends primarily on the change in ______ across the
interface. - (correct Answer) - acoustic impedance
The velocity of sound waves is primarily dependent on - (correct Answer) - medium and mode of vibration
Increasing the frequency of an ultrasonic longitudinal wave will result in ______ in the velocity of that wave. -
(correct Answer) - no change
The change in direction of an ultrasonic beam, when it passes from one medium to another, in which elasticity
and density differ from those of the first medium is called - (correct Answer) - refraction
, A long near zone can be obtained by - (correct Answer) - using a higher frequency transducer
If a 2 MHz frequency is used in human soft tissue, the wavelength is approximately - (correct Answer) - 0.75
mm
The ratio of particle pressure to particle velocity at a given point within the ultrasonic field is - (correct Answer)
- impedance
What is the following formula used to determine?
(2 × velocity of reflector × original frequency) / velocity of sound - (correct Answer) - Doppler shift frequency
The principle that states that all points on a wavefront can be considered as point sources for the production of
sperical secondary wavelets was postulated by - (correct Answer) - Huygens
A 10 dB difference in signal intensity is equivalent to a _______ difference. - (correct Answer) - tenfold
The level below which signals are not transmitted through an ultrasound receiver system is the - (correct
Answer) - threshold, negative, reject level
Gray-scale systems typically use _____ as a means of signal dynamic range reduction. - (correct Answer) -
compression
The strength of the echo is related to the height of the deflection on the oscilloscope for the ____ display. -
(correct Answer) - A-mode
What are methods of restricting the dynamic range of the signal? - (correct Answer) - suppression, rejection,
compression
Most of the scan converters currently in use are of the _____ type? - (correct Answer) - digital
The fraction of time that pulsed ultrasound is actually on is the - (correct Answer) - duty factor
The ability of an imaging system to detect weak reflections is called - (correct Answer) - sensitivity
What image shape is produced by a linear sequenced array transducer? - (correct Answer) - rectangular
The major factor in determining the acoustic power output of the transducer is the - (correct Answer) -
magnitude of the voltage spike
Two primary mechanisms that produce tissue biological effects are - (correct Answer) - thermal and cavitational
The _____ relates bandwidth to operating frequency. - (correct Answer) - quality factor, Q Factor
The extraneous beams of ultrasound generated from the edges of individual transducer elements and not in
the direction of the main ultrasonic beam are called - (correct Answer) - side lobes
The product of the period and the number of cycles in the pulse is the - (correct Answer) - pulse duration
The substance typically used as a matrix on the imaging surface of an analog scan converter tube is - (correct
Answer) - silicon oxide
Example of nonspecular reflector - (correct Answer) - red blood cells
What happens to spatial pulse length when frequency increases? - (correct Answer) - decreases
Axial resolution is dependent on? - (correct Answer) - wavelength
Lateral resolution is dependent on? - (correct Answer) - beam diameter
Where does the beam of an unfocused transducer diverge? - (correct Answer) - Fraunhofer zone
Reverberation artifacts are a result of - (correct Answer) - two or more strong reflecting surfaces
True/False: Grating lobes are essential for the proper operation of a linear phased array. - (correct Answer) -
False
True/False: Electronically steered scanners always produce higher resolution images than do mechanically
steered scanners. - (correct Answer) - False
True/False: An annular array scanner uses mechanical beam steering. - (correct Answer) - True
True/False: A linear sequenced array cannot be dynamically focused. - (correct Answer) - False
registration or B-mode alignment - (correct Answer) - Which AIUM test object function utilizes all the groups of
wires in the AIUM 100 mm test object?
axial resolution - (correct Answer) - Which AIUM test object function utilizes the A group of wires in the AIUM
100 mm test object?
lateral resolution - (correct Answer) - Which AIUM test object function utilizes the B group of wires in the AIUM
100 mm test object?
dead zone - (correct Answer) - Which AIUM test object function utilizes the D group of wires in the AIUM 100
mm test object?
depth calibration - (correct Answer) - Which AIUM test object function utilizes the C or E groups of wires in the
AIUM 100 mm test object?
What happens to axial resolution when spatial pulse length is decreased? - (correct Answer) - improves
How much will a 3.5 MHz pulse be attenuated after passing through 2 cm of soft tissue? - (correct Answer) - 3.5
dB
Propagation speed errors result in - (correct Answer) - improper axial position
Enhancement is caused by - (correct Answer) - weakly attenuating structures
The Doppler shift frequency is - (correct Answer) - directly proportional to the velocity of the reflector
,The number of frames per second necessary for a real-time image to be flicker free is - (correct Answer) - more
than 15
True/False: The SPTA intensity will always be larger than the SATA intensity. - (correct Answer) - True
The intensity of the ultrasound beam is usually greater at the focal zone because of - (correct Answer) - the
smaller beam diameter
If the amplitude is doubled, the intensity is - (correct Answer) - quadrupled
The attenuation for soft tissue is - (correct Answer) - increased with tissue thickness
The acoustic impedance of the matching layer - (correct Answer) - can be chosen to improve transmission into
the body
True/False: In a pulse-echo system, the quality factor should be made as large as possible. - (correct Answer) -
False
True/False: The beam diameter is constant in the near zone. - (correct Answer) - False
The operating frequency is dependent on - (correct Answer) - thickness of the crystal
The period of an ultrasound wave is - (correct Answer) - the time of one wavelength
The dynamic range of a system is - (correct Answer) - the ratio of smallest to largest power level that the
system can handle
True/False: The intensity of an ultrasonic beam can be measured with radiation force balance. - (correct
Answer) - True
Increasing the pulse repetition period - (correct Answer) - increases the maximum depth that can be imaged
Ultrasound bioeffects - (correct Answer) - are not confirmed below 100 mW/cm² SPTA
True/False: No refraction can occur at an interface if the media impedances are equal. - (correct Answer) -
False
True/False: Smaller transducers always produce smaller beam diameters. - (correct Answer) - False
True/False: The ultrasound beam profile can be measured with a hydrophone. - (correct Answer) - True
True/False: The pulsed-Doppler system yields better depth resolution than the continuous wave (CW) system. -
(correct Answer) - True
True/False: The gray-scale display was made possible when digital scan converters replaced analog scan
converters. - (correct Answer) - False
True/False: Videotape recorders operating at 30 frames per second cannot be used with mechanical real-time
units because the fram rate is too slow. - (correct Answer) - False
True/False: Linear phased array scanners need no form of mechanical focusing because focusing is performed
,electronically. - (correct Answer) - False
True/False: The fram rate of real-time scanners depends on the number of lines used to form the image. -
(correct Answer) - True
True/False: It is not possible to steer an annular phased array electronically. - (correct Answer) - True
True/False: The near zone length should be kept as short as possible. - (correct Answer) - False
What percentage of intensity of an ultrasound pulse incident on an interface of 0.25 and 0.75 rayls is reflected?
- (correct Answer) - 25%
Axial resolution can be improved by using - (correct Answer) - higher frequency transducers
When particle motion of a medium is parallel to the direction of a wave propagation, the wave being
transmitted is called a - (correct Answer) - longitudinal wave
The wavelength in a material having a wave velocity of 1500 m/s emplying a transducer frequency of 5 MHz is -
(correct Answer) - 0.3 mm
The factor that determines the amount of reflection at the interface of two dissimilar materials is - (correct
Answer) - difference in acoustic impedances
The equation that describes the relationship among propagation, wavelength, and frequency is - (correct
Answer) - λ = c/ƒ
What three things can occur when an ultrasonic beam reaches the interface of two dissimilar materials? -
(correct Answer) - reflection, refraction, mode conversion
The acoustic impedance of a material is - (correct Answer) - equal to the product of density and velocity
The average velocity of ultrasonic waves in soft tissue is - (correct Answer) - 1540 m/s
True/False: Receiver-angle values in CW Doppler analysis do not influence the final Doppler shift. - (correct
Answer) - False
Refraction occurs because of difference in ______ across an interface between two materials - (correct Answer)
- wave velocity
Reflection factor at an interface between two materials depends primarily on the change in ______ across the
interface. - (correct Answer) - acoustic impedance
The velocity of sound waves is primarily dependent on - (correct Answer) - medium and mode of vibration
Increasing the frequency of an ultrasonic longitudinal wave will result in ______ in the velocity of that wave. -
(correct Answer) - no change
The change in direction of an ultrasonic beam, when it passes from one medium to another, in which elasticity
and density differ from those of the first medium is called - (correct Answer) - refraction
, A long near zone can be obtained by - (correct Answer) - using a higher frequency transducer
If a 2 MHz frequency is used in human soft tissue, the wavelength is approximately - (correct Answer) - 0.75
mm
The ratio of particle pressure to particle velocity at a given point within the ultrasonic field is - (correct Answer)
- impedance
What is the following formula used to determine?
(2 × velocity of reflector × original frequency) / velocity of sound - (correct Answer) - Doppler shift frequency
The principle that states that all points on a wavefront can be considered as point sources for the production of
sperical secondary wavelets was postulated by - (correct Answer) - Huygens
A 10 dB difference in signal intensity is equivalent to a _______ difference. - (correct Answer) - tenfold
The level below which signals are not transmitted through an ultrasound receiver system is the - (correct
Answer) - threshold, negative, reject level
Gray-scale systems typically use _____ as a means of signal dynamic range reduction. - (correct Answer) -
compression
The strength of the echo is related to the height of the deflection on the oscilloscope for the ____ display. -
(correct Answer) - A-mode
What are methods of restricting the dynamic range of the signal? - (correct Answer) - suppression, rejection,
compression
Most of the scan converters currently in use are of the _____ type? - (correct Answer) - digital
The fraction of time that pulsed ultrasound is actually on is the - (correct Answer) - duty factor
The ability of an imaging system to detect weak reflections is called - (correct Answer) - sensitivity
What image shape is produced by a linear sequenced array transducer? - (correct Answer) - rectangular
The major factor in determining the acoustic power output of the transducer is the - (correct Answer) -
magnitude of the voltage spike
Two primary mechanisms that produce tissue biological effects are - (correct Answer) - thermal and cavitational
The _____ relates bandwidth to operating frequency. - (correct Answer) - quality factor, Q Factor
The extraneous beams of ultrasound generated from the edges of individual transducer elements and not in
the direction of the main ultrasonic beam are called - (correct Answer) - side lobes
The product of the period and the number of cycles in the pulse is the - (correct Answer) - pulse duration
The substance typically used as a matrix on the imaging surface of an analog scan converter tube is - (correct
Answer) - silicon oxide
