CCI - Cardiovascular Credentialing International Peripheral Venous Evaluation Questions and Answers — Questions and Answers
Question 1: A sonographer performing a lower extremity venous duplex exam on a patient with unilateral leg swelling obtains a continuous, non-phasic Doppler waveform from the left common femoral vein. The right common femoral vein displays a normal phasic waveform. This finding is most suggestive of which condition?
- Normal variant in a shallow breather
- Acute deep vein thrombosis (DVT) in the ipsilateral popliteal vein
- Extrinsic compression of the contralateral iliac vein
- Obstruction in the left iliac vein or inferior vena cava (Correct answer)
Correct answer: Obstruction in the left iliac vein or inferior vena cava
Normal venous flow in the lower extremities is phasic with respiration, decreasing with inspiration and increasing with expiration. A continuous, non-phasic waveform indicates a loss of this respiratory variation, which is typically caused by a more proximal obstruction, such as DVT or extrinsic compression (e.g., May-Thurner syndrome) in the iliac veins or IVC, preventing the pressure changes from the thorax from reaching the more distal veins.
Question 2: During a venous reflux study, the sonographer documents retrograde flow in the great saphenous vein (GSV) that lasts for 950 milliseconds following distal augmentation. How should this finding be classified?
- Normal valvular function
- Severe deep venous reflux
- Pathologic superficial venous reflux (Correct answer)
- Equivocal for reflux
Correct answer: Pathologic superficial venous reflux
The standard threshold for diagnosing pathologic venous reflux in the superficial venous system (including the great and small saphenous veins) is a retrograde flow duration of greater than 500 milliseconds (>0.5 seconds). Since 950 ms is significantly longer than 500 ms, this finding indicates valvular incompetence and is classified as pathologic superficial venous reflux.
Question 3: Which of the following is considered the most reliable and primary sonographic criterion for diagnosing an acute deep vein thrombosis (DVT)?
- Visualization of echogenic material within the vein lumen
- Lack of complete coaptation of the vein walls with transducer pressure (Correct answer)
- Absence of spontaneous flow on spectral Doppler
- Enlarged vein diameter compared to the adjacent artery
Correct answer: Lack of complete coaptation of the vein walls with transducer pressure
While other findings like echogenic material, absent Doppler signals, and venous distention are supportive signs, the primary and most definitive diagnostic criterion for DVT is the inability to fully compress the vein walls together (coaptation) with gentle transducer pressure. A patent vein will collapse completely, whereas a vein containing thrombus will not.
Question 4: A patient is referred for a peripheral venous evaluation due to a high clinical suspicion for DVT. The factors contributing to thrombus formation, known as Virchow's Triad, consist of which of the following three elements?
- Arterial stenosis, hypertension, and hyperlipidemia
- Venous stasis, endothelial injury, and hypercoagulability (Correct answer)
- Valvular incompetence, venous dilation, and chronic inflammation
- Lymphedema, obesity, and arterial insufficiency
Correct answer: Venous stasis, endothelial injury, and hypercoagulability
Virchow's Triad describes the three broad categories of factors that are thought to contribute to thrombosis. These are: 1) venous stasis (slow blood flow), 2) endothelial injury (damage to the vein wall), and 3) a hypercoagulable state (blood that is prone to clotting).
Question 5: When scanning the popliteal fossa from a posterior approach, what is the typical anatomical relationship between the popliteal vein and the popliteal artery on the ultrasound screen?
- The vein is lateral to the artery
- The vein is deep (further from the transducer) to the artery
- The artery is not visible in this view
- The vein is superficial (closer to the transducer) to the artery (Correct answer)
Correct answer: The vein is superficial (closer to the transducer) to the artery
When imaging from the posterior aspect of the knee (the popliteal fossa), the popliteal vein is typically located superficial to the popliteal artery. Therefore, on the ultrasound display, the vein will appear closer to the top of the screen than the artery.
Question 6: A sonographer asks a patient to perform the Valsalva maneuver during a venous insufficiency study while interrogating the saphenofemoral junction. What is the primary purpose of this technique?
- To assess for deep vein thrombosis in the iliac veins
- To increase arterial inflow to the lower extremities
- To increase intra-abdominal pressure and test for valvular competence (Correct answer)
- To decrease the heart rate and improve Doppler signal quality
Correct answer: To increase intra-abdominal pressure and test for valvular competence
The Valsalva maneuver (straining against a closed glottis) significantly increases intra-thoracic and intra-abdominal pressure. This pressure is transmitted down the venous system. In a patient with competent valves, this will cause flow to slow or cease. If the valves are incompetent, the increased proximal pressure will cause blood to flow backward (reflux) past the faulty valve, which can be detected by Doppler.
CCI - Cardiovascular Credentialing International Peripheral Venous Evaluation Questions and Answers
A sonographer performing a lower extremity venous duplex exam on a patient with unilateral leg swelling obtains a continuous, non-phasic Doppler waveform from the left common femoral vein.
The right common femoral vein displays a normal phasic waveform.
This finding is most suggestive of which condition?