Strain gauge plethysmography in the assessment of venous reflux after subfascial closure of perforating veins: a prospective study of twenty patients.

Doppler ultrasonography and strain gauge plethysmography were used prospectively to study the hemodynamic changes in 20 patients' (5 men and 15 women) legs operated on by means of subfascial closure for insufficiency of perforating veins. In 10 patients (50%) the valves of the deep veins were incompetent as verified by Doppler ultrasonography, and deep vein thrombosis had previously been diagnosed in seven patients. After subfascial ligature, strain gauge plethysmography showed no changes in arterial flow, venous capacity, or in venous emptying rate. However, both venous reflux flow and reflux volume were significantly lowered (p less than 0.01) after surgery as compared to values before operation. The clinical objective results were good in all cases. In two of four patients with fair subjective results the arterial flow was pathologically high, which probably implies the presence of microscopic arteriovenous fistulas. It is concluded that strain gauge plethysmography can quantitate the change in deep venous reflux after ligation of perforating veins.