DMS 111 Final Exam Concepts 2026 – Diagnostic Medical Sonography
Fundamentals and Imaging Study Guide
Spatial pulse length is determined by ________________ & ________________. - correct
answer ✔✔ wavelength; number of cycles in a pulse
The useful frequency range for most diagnostic applications is - correct answer ✔✔ 2 to 15 MHz
Frequencies up to 50 MHz are used in ______________ & _________________ &
_________________ imaging. - correct answer ✔✔ ophthalmologic, dermatologic and
intravascular
The transducer element has impedance that is about ________________ times that of tissue -
correct answer ✔✔ 20
Increasing transducer frequency decreases the _________________ while increasing
________________ - correct answer ✔✔ maximum penetration depth; detail resolution
Shortening the pulses broadens the ___________________. - correct answer ✔✔ bandwidth
Damping material is attached to the __________ face of the transducer element to
____________ the number of cycles to each pulse. - correct answer ✔✔ rear; reduce
At double the near-zone length, the beam diameter is ______________ to the diameter of the
transducer element. - correct answer ✔✔ equal
Thinner elements operate at ______________ frequencies. - correct answer ✔✔ higher
,If the aperture or frequency increases, the near-zone length ______________. - correct answer
✔✔ increases
The matching layer has impedance of some intermediate value between those of the
____________________ & _______________. - correct answer ✔✔ transducer element and
the skin
The ______________, _________________, and ______________ determine the beam width
at the focus. - correct answer ✔✔ aperture; focal length & wavelength
Multiple _______________ can be used to achieve a long focus. - correct answer ✔✔ focal
zones
Utilizing multiple focal zones decreases __________________. - correct answer ✔✔ temporal
resolution (frame rate)
CW (continuous wave) transducers are not ____________ because pulses are not used. - correct
answer ✔✔ damped
Operating frequency is determined by the ________________ and the _______________. -
correct answer ✔✔ propagation speed; thickness of the element
Imaging resolution has three aspects: ______________, ______________ and
__________________. - correct answer ✔✔ detail; contrast; temporal resolution
Wide bandwidth allows for ________________. - correct answer ✔✔ harmonic imaging
To increase the number of foci, pulse repetition frequency must ___________________ -
correct answer ✔✔ Increase
, To increase the number of lines per frame (LPF), pulse repetition frequency must
________________ - correct answer ✔✔ Increase
To increase the frame rate (FR), pulse repetition frequency must ______________ - correct
answer ✔✔ Increase
If the lines per frame decreases, frame rate ______________ - correct answer ✔✔ Increases
If penetration increases, pulse repetition frequency must _______________ - correct answer
✔✔ Decrease
If penetration increases, frame rate _______________ - correct answer ✔✔ Decreases
If the number of foci increases, frame rate ______________ - correct answer ✔✔ Decreases
If the lines per frame increases, frame rate ______________ - correct answer ✔✔ Decreases
A rectangular matrix measures .... - correct answer ✔✔ 1024 x 768 or 512 x 384
The harmonic beam is much narrower than the primary beam and therefore improves
_______________ resolution - correct answer ✔✔ Lateral resolution
Harmonics are generated only in the _____________ portion of the beam - correct answer ✔✔
Highest-intensity
A-mode presents a ____________ versus an _____________ display - correct answer ✔✔
Depth, echo-amplitude
Fundamentals and Imaging Study Guide
Spatial pulse length is determined by ________________ & ________________. - correct
answer ✔✔ wavelength; number of cycles in a pulse
The useful frequency range for most diagnostic applications is - correct answer ✔✔ 2 to 15 MHz
Frequencies up to 50 MHz are used in ______________ & _________________ &
_________________ imaging. - correct answer ✔✔ ophthalmologic, dermatologic and
intravascular
The transducer element has impedance that is about ________________ times that of tissue -
correct answer ✔✔ 20
Increasing transducer frequency decreases the _________________ while increasing
________________ - correct answer ✔✔ maximum penetration depth; detail resolution
Shortening the pulses broadens the ___________________. - correct answer ✔✔ bandwidth
Damping material is attached to the __________ face of the transducer element to
____________ the number of cycles to each pulse. - correct answer ✔✔ rear; reduce
At double the near-zone length, the beam diameter is ______________ to the diameter of the
transducer element. - correct answer ✔✔ equal
Thinner elements operate at ______________ frequencies. - correct answer ✔✔ higher
,If the aperture or frequency increases, the near-zone length ______________. - correct answer
✔✔ increases
The matching layer has impedance of some intermediate value between those of the
____________________ & _______________. - correct answer ✔✔ transducer element and
the skin
The ______________, _________________, and ______________ determine the beam width
at the focus. - correct answer ✔✔ aperture; focal length & wavelength
Multiple _______________ can be used to achieve a long focus. - correct answer ✔✔ focal
zones
Utilizing multiple focal zones decreases __________________. - correct answer ✔✔ temporal
resolution (frame rate)
CW (continuous wave) transducers are not ____________ because pulses are not used. - correct
answer ✔✔ damped
Operating frequency is determined by the ________________ and the _______________. -
correct answer ✔✔ propagation speed; thickness of the element
Imaging resolution has three aspects: ______________, ______________ and
__________________. - correct answer ✔✔ detail; contrast; temporal resolution
Wide bandwidth allows for ________________. - correct answer ✔✔ harmonic imaging
To increase the number of foci, pulse repetition frequency must ___________________ -
correct answer ✔✔ Increase
, To increase the number of lines per frame (LPF), pulse repetition frequency must
________________ - correct answer ✔✔ Increase
To increase the frame rate (FR), pulse repetition frequency must ______________ - correct
answer ✔✔ Increase
If the lines per frame decreases, frame rate ______________ - correct answer ✔✔ Increases
If penetration increases, pulse repetition frequency must _______________ - correct answer
✔✔ Decrease
If penetration increases, frame rate _______________ - correct answer ✔✔ Decreases
If the number of foci increases, frame rate ______________ - correct answer ✔✔ Decreases
If the lines per frame increases, frame rate ______________ - correct answer ✔✔ Decreases
A rectangular matrix measures .... - correct answer ✔✔ 1024 x 768 or 512 x 384
The harmonic beam is much narrower than the primary beam and therefore improves
_______________ resolution - correct answer ✔✔ Lateral resolution
Harmonics are generated only in the _____________ portion of the beam - correct answer ✔✔
Highest-intensity
A-mode presents a ____________ versus an _____________ display - correct answer ✔✔
Depth, echo-amplitude
