Quantification of venous reflux by means of duplex scanning.

Venous reflux in milliliters per second has been measured in individual veins with duplex scanning. Forty-six patients (47 legs) with symptomatic varicose veins have been studied while they were in the erect position. Nineteen legs had skin changes whereas the rest (28 legs) had only varicose veins with no skin changes. In 45 limbs, reflux was confined to one vein only: long saphenous vein in 28, short saphenous vein in nine, and femoropopliteal vein in eight. In one limb, reflux was found in the long saphenous, short saphenous, and femoropopliteal veins, and in another it was found in the long and short saphenous veins. In the latter two limbs the amount of reflux found in each vein was added to obtain the total reflux in the limb. In the limbs with skin changes, reflux (median +/- 90% tolerance levels) was 30 (10 to 53) ml/sec; whereas in limbs with no skin changes it was 10 (3 to 44) ml/sec. Reflux greater than 10 ml/sec was associated with a high incidence of skin changes (66%) irrespective of whether this was in the superficial or deep veins; reflux less than 10 ml/sec was not associated with skin changes.