VT Diagnostic Imaging Techniques 4

Question 1

Digital subtraction angiography (DSA) improves vessel visualization by:

Accepted Answer

Subtracting a pre-contrast mask image from contrast-filled images

Answer

DSA electronically subtracts a baseline (mask) image acquired before contrast injection from subsequent images, leaving only the opacified vessels visible.

Question 2

Which transducer type is preferred for imaging deep abdominal vessels such as the aorta?

Accepted Answer

Curvilinear low-frequency (2–5 MHz)

Answer

Curvilinear transducers with low-frequency elements (2–5 MHz) provide the penetration depth needed to image the aorta and iliac vessels through the abdomen.

Question 3

The primary advantage of power Doppler over conventional color Doppler is:

Accepted Answer

Greater sensitivity to low-velocity flow

Answer

Power Doppler displays the amplitude (power) of the Doppler signal rather than velocity, making it more sensitive to slow flow but sacrificing directional information.

Question 4

In MR angiography, 'time-of-flight' technique generates vessel contrast by:

Accepted Answer

Exploiting the inflow of unsaturated spins into a saturated imaging slab

Answer

Time-of-flight MRA relies on flowing blood entering a pre-saturated imaging plane with full magnetization, appearing bright relative to the saturated stationary tissue.

Question 5

Which finding on duplex ultrasound is MOST consistent with acute deep vein thrombosis (DVT)?

Accepted Answer

Non-compressible vein with absent flow on compression

Answer

Acute DVT is diagnosed when the vein fails to fully collapse under transducer compression and color Doppler shows absent or reduced flow at that segment.

(VT) Vascular Technician Certification Practice Test

(VT) Vascular Technician Certification Practice Test

VT Diagnostic Imaging Techniques 4