Where does venous reflux start?

Purpose: This study was designed to identify the origin of lower limb primary venous reflux in asymptomatic young individuals and to compare patterns of reflux with age-matched subjects with prominent or clinically apparent varicose veins. Methods: Forty age- and sex-matched subjects with no symptoms (age, 15 to 35 years; 80 limbs; group A), 20 subjects (age, 19 to 32 years; 40 limbs) with prominent but nonvaricose veins (n = 26 limbs; group B), and 50 patients (age, 17 to 34 years; 100 limbs) with varicose veins (n = 64; group C) were examined with color flow duplex imaging. All proximal veins (above popliteal skin crease), superficial, perforator, and deep, in the lower limb were examined in the standing position, and all the distal veins in the sitting position. Patients who had a documented episode of superficial or deep vein thrombosis, previous venous surgery, or injection sclerotherapy were excluded from the study. Results: The prevalence of reflux: in group A was 14% (11 of 80), in group B 77% (31 of 40), and in group C 87% (87 of 100). In more than 80% of limbs in the three groups, reflux was confined to the superficial veins alone. Deep venous reflux: or combined patterns of reflux were uncommon even in group C. Reflux was detected in all segments of the saphenous veins and their tributaries. In the 125 limbs that had superficial venous incompetence, the below-knee segment of the greater saphenous vein was the most common site of reflux (85, 68%), followed by the above-knee segment of greater saphenous vein (69, 55%) and the saphenofemoral junction (41, 32%). Nonsaphenous reflux was rare (3, 2.4%). Reflux in the lesser saphenous vein (21, 17%) was seen in all groups, whereas involvement of both greater and lesser saphenous veins (8, 6.4%) was seen in group C alone. The incidence of multisegmental reflux was significantly higher in group C (61 of 64, 95%) than in group A (two of 11, 18%) or group B (14 of 26, 54%). The prevalence of distal reflux was comparable in all groups. Conclusions: Primary venous reflux can occur in any superficial or deep vein of the lower limbs. The below-knee veins are often involved in asymptomatic individuals and in these who have prominent or varicose veins. These data suggest that reflux appears to be a local or multifocal process in addition to or separate from a retrograde process.