VT DVT & Venous Reflux Assessment 2 — Questions and Answers
Question 1: During duplex evaluation of the femoral vein, which finding is MOST consistent with acute DVT?
- Hyperechoic, compressible thrombus
- Anechoic, non-compressible lumen with absent color fill (Correct answer)
- Echogenic wall thickening with normal compressibility
- Augmented flow with distal compression
Correct answer: Anechoic, non-compressible lumen with absent color fill
Acute DVT typically appears anechoic or hypoechoic with failure to compress and absent color flow filling the lumen.
Question 2: Venous reflux in the great saphenous vein (GSV) is defined as retrograde flow lasting longer than:
- 0.5 seconds (Correct answer)
- 1.0 second
- 2.0 seconds
- 3.0 seconds
Correct answer: 0.5 seconds
For superficial veins such as the GSV, reflux is defined as retrograde flow exceeding 0.5 seconds with Valsalva or manual compression-release.
Question 3: Which maneuver is BEST used to provoke reflux in the great saphenous vein at the saphenofemoral junction?
- Distal augmentation
- Valsalva maneuver (Correct answer)
- Trendelenburg positioning
- Pneumatic cuff deflation at the thigh
Correct answer: Valsalva maneuver
Valsalva increases intra-abdominal pressure, challenging the saphenofemoral junction valve and best provoking GSV reflux at that level.
Question 4: A patient has a positive tourniquet test. This finding suggests venous incompetence at which level?
- Deep system perforators only
- Above the tourniquet placement (Correct answer)
- Below the tourniquet placement
- At the popliteal fossa only
Correct answer: Above the tourniquet placement
In the tourniquet (Trendelenburg) test, rapid refilling above the occluding tourniquet implies superficial incompetence proximal to that level.
Question 5: Chronic DVT is distinguished from acute DVT on duplex ultrasound primarily by:
- Complete absence of color flow
- Vein wall thickening, scarring, and echogenic thrombus (Correct answer)
- Anechoic thrombus with soft consistency
- Normal respiratory phasicity
Correct answer: Vein wall thickening, scarring, and echogenic thrombus
Chronic DVT shows hyperechoic, organized thrombus with wall thickening, fibrosis, recanalization channels, and reduced vein diameter.
Question 6: Which deep vein is MOST commonly involved in calf DVT detected by duplex ultrasound?
- Popliteal vein
- Peroneal vein (Correct answer)
- Femoral vein
- External iliac vein
Correct answer: Peroneal vein
The peroneal (fibular) veins are the most frequently thrombosed calf deep veins, followed by the posterior tibial veins.
Question 7: When using pneumatic cuff deflation to assess venous reflux, the cuff is typically inflated to what pressure before rapid release?
- 20 mmHg
- 40 mmHg
- 80 mmHg (Correct answer)
- 120 mmHg
Correct answer: 80 mmHg
An 80 mmHg pneumatic cuff is inflated distally then rapidly deflated to standardize venous reflux provocation across labs.
VT DVT & Venous Reflux Assessment 2
During duplex evaluation of the femoral vein, which finding is MOST consistent with acute DVT?