VT Venous Mapping & Preoperative Assessment 2 — Questions and Answers
Question 1: What does the venous filling index (VFI) measured by air plethysmography (APG) primarily quantify?
- Arterial inflow adequacy to the limb
- Calf muscle pump ejection fraction
- Rate and degree of venous reflux (Correct answer)
- Ambulatory venous pressure
Correct answer: Rate and degree of venous reflux
The VFI reflects how rapidly the venous volume of the leg refills after exercise, serving as a quantitative measure of the severity of venous reflux.
Question 2: At the saphenofemoral junction (SFJ), the GSV drains into which vessel?
- Superficial femoral vein
- Common femoral vein (Correct answer)
- Popliteal vein
- Femoral vein at Hunter's canal
Correct answer: Common femoral vein
The GSV joins the common femoral vein at the SFJ, located in the femoral triangle just below the inguinal ligament.
Question 3: In the CEAP classification, which condition does the subclass C4b describe?
- Varicose veins with telangiectasia
- Skin pigmentation or venous eczema
- Lipodermatosclerosis or atrophie blanche (Correct answer)
- Non-pitting edema
Correct answer: Lipodermatosclerosis or atrophie blanche
C4b specifically identifies lipodermatosclerosis (fibrotic skin thickening) or atrophie blanche (white scarred skin), which represent more advanced skin changes than C4a.
Question 4: What is the minimum reflux duration at the saphenofemoral junction that is considered pathologic on duplex ultrasound?
- >0.3 seconds
- >0.5 seconds (Correct answer)
- >1.0 second
- >2.0 seconds
Correct answer: >0.5 seconds
Reflux duration exceeding 0.5 seconds in the superficial venous system (including the SFJ) is the accepted threshold for pathologic incompetence.
Question 5: When performing GSV mapping for CABG, which set of parameters must be documented along the vein course?
- Peak systolic velocity at each segment
- Diameter, continuity, compressibility, and marked skin location (Correct answer)
- Color flow direction and augmentation response only
- Resistive index and pulsatility index
Correct answer: Diameter, continuity, compressibility, and marked skin location
Comprehensive GSV mapping documents luminal diameter at multiple levels, vein continuity, wall compressibility confirming patency, and the skin-marked course for intraoperative guidance.
Question 6: The perforating veins of Cockett are clinically significant in venous ulcer disease and are located in which anatomical region?
- Lateral thigh
- Popliteal fossa
- Medial lower leg (Correct answer)
- Dorsum of the foot
Correct answer: Medial lower leg
Cockett's perforators connect the posterior arch vein to the posterior tibial veins along the medial lower leg, directly beneath the gaiter zone where venous ulcers typically occur.
Question 7: Which duplex finding best distinguishes secondary varicose veins from primary varicose veins?
- Vein diameter consistently exceeding 4 mm
- Reflux duration exceeding 1.0 second in the GSV
- Deep venous obstruction or reflux causing superficial venous dilation (Correct answer)
- Absence of saphenofemoral junction incompetence
Correct answer: Deep venous obstruction or reflux causing superficial venous dilation
Secondary varicose veins develop as a consequence of identifiable deep venous pathology (obstruction or reflux), whereas primary varicose veins arise without an underlying deep venous cause.
VT Venous Mapping & Preoperative Assessment 2
What does the venous filling index (VFI) measured by air plethysmography (APG) primarily quantify?