UTC Ultrasound Physics & Instrumentation 2

Question 1

In pulsed wave Doppler, the Nyquist limit represents which value?

Accepted Answer

Half the pulse repetition frequency (PRF/2), the maximum detectable Doppler shift without aliasing

Answer

The Nyquist limit equals PRF/2; Doppler shift frequencies exceeding this limit result in aliasing, where high-velocity flows are misrepresented as flowing in the opposite direction.

Question 2

Which transducer type fires elements sequentially to produce a rectangular field of view, making it ideal for vascular and musculoskeletal imaging?

Accepted Answer

Linear array

Answer

Linear array transducers fire elements sequentially to produce a flat, rectangular image, providing excellent near-field resolution for superficial structures such as vessels and tendons.

Question 3

The Doppler effect used in ultrasound refers to which phenomenon?

Accepted Answer

Change in received frequency caused by relative motion between the sound source and a moving reflector

Answer

The Doppler effect is the change in received frequency compared to transmitted frequency due to relative motion between the transducer and moving reflectors such as blood cells.

Question 4

What is the primary advantage of tissue harmonic imaging over fundamental (conventional) imaging?

Accepted Answer

Reduced near-field artifacts and improved contrast resolution

Answer

Tissue harmonic imaging uses harmonics generated within tissue (at twice the transmitted frequency) rather than the fundamental frequency, reducing artifacts and clutter while improving contrast resolution.

Question 5

A phased array transducer is most commonly used for which clinical application?

Accepted Answer

Cardiac (echocardiographic) imaging through narrow intercostal windows

Answer

Phased array transducers steer the beam electronically through a small footprint, allowing cardiac imaging through the narrow intercostal spaces between the ribs.

(UTC) Ultrasound Technologist Certification Practice Test

(UTC) Ultrasound Technologist Certification Practice Test

UTC Ultrasound Physics & Instrumentation 2