DUPLEX-DERIVED VALVE CLOSURE TIMES FAIL TO CORRELATE WITH REFLUX FLOWVOLUMES IN PATIENTS WITH CHRONIC VENOUS INSUFFICIENCY

The best way to quantitate venous reflux is still a matter of debate. Duplex-derived valve closure times (VCTs) have been used recently beca use they can be measured easily. We examined the relationships between VCT and duplex-obtained quantitation of venous volume and between VCT and air plethysmography (APG). Sixty-nine legs in 45 patients with va rying clinical degrees of chronic venous insufficiency were studied by duplex scan and APG. VCTs were compared with duplex-derived flow calc ulations and with APG-derived venous filling index and residual volume fraction. The patients' mean age was 47.5 +/- 13.9 pears; the mean du ration of their symptoms was 13 +/- 4 years. Twenty percent had a hist ory of deep venous thrombosis, and 29% had undergone venous surgery. N o correlation was found between VCT and how volume or between VCT and flow at peak reflux at any of the anatomic locations studied: saphenof emoral junction, greater saphenous vein, lesser saphenous vein, superf icial femoral vein, profunda femoris vein, and popliteal vein. Likewis e, no correlation was found between total VCT and APG-derived venous f illing index or between total flow volumes and APG-derived residual vo lume fraction. Total VCT and total flow volumes did, however, have a m oderate correlation (r = 0.65; p = 0.0003). Duplex-derived VCTs, altho ugh extremely useful in determining the presence of reflux, do not cor relate with the magnitude of reflux, and should not be used to quantit ate the degree of reflux.