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The place of duplex scanning for varicose veins and common venous problems.

Duplex scanning has become the 'gold standard' for confirming reflux and demonstrating anatomy in cases of lower limb venous disease. However, the large numbers of patients presenting with varicose veins (or with skin changes and ulcers) mean that routine use of duplex is impractical, and this investigation has still not become well established in many hospitals. In order to determine the proportion of patients likely to require duplex scanning (and other special tests-photoplethysmography and ascending venography) we reviewed a consecutive series of 201 patients referred to the vascular clinic of a district general hospital with 283 symptomatic limbs affected by varicose veins and/or skin changes and ulcers. Patients were examined clinically and with hand-held Doppler. Duplex scanning was then requested to check for reflux in the popliteal fossa and to examine the groin and residual long saphenous vein in some cases of recurrent varicose veins. Duplex scanning was required in 51 (18%) limbs, venography in 8 (3%), and photoplethysmography in only one limb. In total, special tests were needed in 60 (21%) limbs. Subsequently, 198 (70%) limbs were referred for surgery. We would now (in 1996) duplex scan every case with popliteal fossa reflux and most recurrences. Had all these been scanned, then 79 (28%) would have had special tests. This knowledge should help in planning the implications of a duplex scanning service for varicose veins, skin changes and ulcers.