Further insight in selecting the ideal vein for lymphaticovenous anastomosis: utilizing the anatomy and Venturi effect of a small vein/venule draining into the main vein

The functional and dilated lymphatic vessel and veins with minimal backflow and pressure are considered ideal for lymphaticovenous anastomsosis (LVA). However, how to select the ideal vein remains to be determined. This study aims to provide further insight in selecting the ideal vein.This is a retrospective study evaluating 166 limbs with lymphedema with a minimal follow-up period of 12 months. The surgical approach included side-to-end LVA where one group used a non-Venturi LVA and the other used a small branch draining into a major vein (Venturi LVA). Preoperative, postoperative 1, 3, 6, 12 months limb volume, circumference, reduction volume and ratio were evaluated.The postoperative volume reduction was significant for both groups when compared to their respective preoperative volume. When compared between the 2 groups, the Venturi LVA had a significantly higher reduction volume and ratio at postoperative 1 month (240.82±260.73 cm³ vs 364.27±364.08 cm³, 6.13±5.62% vs 8.77±6.64%; p<0.05) and at 3 months (289.19±291.42 cm³ vs 432.50±395.04cm³, 7.31 ± 6.39% vs 10.55 ± 6.88%; p<0.05) However, the reduction volume and ratio was not significant towards month 6 and 12.This study provides further insight in selecting the ideal vein for LVA. By using a small vein draining into the main vein, valves play a role in reducing backflow. Furthermore, the Venturi effect allows significantly enhanced drainage especially in the initial period after surgery. The effect slowly plateaus after few months ultimately having a similar outcome of reduction at 12 months.