Clinical significance of standing versus reversed trendelenburg position for the diagnosis of lower-extremity venous reflux in the great saphenous vein

Introduction. - Sonographic detection of incompetence in the deep and superficial veins requires proper patient positioning. Although these tests have been traditionally performed in the reversed Trendelenburg (RT) position, recent mandates from The Intersocietal Commission for the Accreditation of Vascular Laboratories and some insurance providers require that patients be evaluated for reflux in the standing position (SP). The purpose of this study was to determine whether performing venous duplex in the SP versus RT position adds information that affects patient treatment. Methods. - Twenty-eight subjects (25 women; mean age of 52 years) with signs and symptoms of venous insufficiency were evaluated prospectively with the use of ultrasound imaging and Doppler in the 5- to 8-MHz ranges. The great saphenous vein (GSV) was evaluated for each limb from below the knee to the saphenofemoral junction. Patients were initially evaluated at 15-25 degrees of RT position. Reflux was defined by reversal of flow for >0.5 seconds via use of the Valsalva and/or manual compression maneuvers. The GSV was measured in A-P diameter at the saphenofemoral junction and at the knee level. The subjects were then elevated to SP and measurements were repeated while the limb was in a nonweight-bearing position. Results. - A total of 52 limbs were evaluated for venous reflux in 28 study subjects. The mean lower-extremity CEAP score was 3 SD ± 3. Twenty-six (50%) GSVs were positive for venous reflux in the RT position. Of these GSVs, three were negative for reflux in SP. Twenty-seven (53%) GSVs were positive for venous reflux in SP; however, four of these GSVs were negative for reflux in RT. The median difference in reflux time from RT to SP was 0.15 seconds (interquartile range 0-3.8 seconds and 0-2.7seconds, respectively, p = 0.02). The mean difference in GSV diameter from RT to SP was 0.7 mm (±0.96 mm SD, p < 0.0001). These results changed the clinical course for one subject who did not have reflux in RT but did in SP (3.5%, p = 0.085). Conclusion. - The results from evaluating subjects in SP were not independently associated with a change in clinical outcome. However, 15% of GSVs negative for reflux in RT were positive for reflux in the SP. As a result, 3.5% of subjects in our study had a change in clinical course as the result of evaluation of the GSV in SP. This finding suggests that failure to identify GSV reflux in RT in patients with signs and symptoms of venous insufficiency may be an indication to evaluate the GSV in SP.