PROSPECTIVE-STUDY OF DUPLEX SCANNING FOR VENOUS REFLUX - COMPARISON OF VALSALVA AND PNEUMATIC CUFF TECHNIQUES IN THE REVERSE TRENDELENBURG AND STANDING POSITIONS

Purpose: To achieve uniform testing of venous reflux between instituti ons, comparable methods of testing by duplex scanning are desired. Thi s study directly examines differences of testing by two techniques, Va lsalva and rapid cuff deflation, performed in two positions: 15-degree reverse Trendelenburg (RT-15) and standing. Methods: Duplex examinati on of 22 extremities in 19 patients with moderate to severe, class 2 a nd 3 chronic venous insufficiency symptoms were compared with duplex s canning of 21 limbs in 11 normal, healthy volunteers. Duration of retr ograde flow and peak velocity were measured in 247 venous segments. Al l extremities were studied in four ways: RT-15 Valsalva, standing Vals alva, RT-15 cuff, and standing cuff. Reflux was defined as duration of retrograde flow or reflux time greater than 0.5 seconds. Six venous s egments were examined: common femoral, superficial femoral, deep femor al, and greater saphenous in the upper thigh, popliteal, and posterior tibial (at the ankle). Results: The results of testing the Valsalva t echnique and the cuff in both the RT-15 and standing non-weight bearin g positions indicate that the Valsalva method is best performed in the RT-15 position as opposed to standing, whereas the cuff technique is more effective in the standing position. In symptomatic limbs, the RT- 15 Valsalva method showed similar proportion of reflux in the upper th igh when compared with the standing cuff method: common femoral (90% v s 67%), superficial femoral (81% vs 71%), greater saphenous (88% vs 59 %), and deep femoral veins (30% vs 15%). In the popliteal vein the sta nding cuff test showed similar proportion of reflux (77%) as compared with the RT-15 Valsalva test (68%); however, a case-by-case analysis i dentified a large amount of variability between techniques, and incons istencies could not be used to identify one technique as better than t he other. Examination of the posterior tibial veins by all methods pro duced inconsistencies and a low yield of reflux in symptomatic limbs. In the common femoral vein, RT-15 Valsalva testing produced reflux tim es of up to 1.5 seconds in normal limbs, and represented ''physiologic reflux.'' There was no recognizable effect of iliac vein valves on te sting distal venous segments by Valsalva maneuver. Conclusions: Reflux in the upper thigh veins - common femoral, superficial femoral, deep femoral, and greater saphenous-is similarly demonstrated in both norma l and symptomatic states by cuff deflation and RT-15 Valsalva techniqu es. In the popliteal vein, discrepancies between these two techniques are identified in patients with chronic venous insufficiency, and tibi al vein reflux is not well demonstrated by either technique. Further i nvestigation is needed to determine ideal techniques for identifying p opliteal and tibial vein reflux.