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

Background: The functional and dilated lymphatic vessel and veins with minimal backflow and pressure are considered ideal for lymphaticovenous anastomosis (LVA). How to select the ideal vein remains to be determined. This study aimed to provide further insight into selecting the ideal vein. Methods: 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, including 1 group with a non-Venturi LVA and another with a small branch draining into a major vein (Venturi LVA). Preoperative and 1, 3, 6, and 12 months postoperative limb volume, circumference, reduction volume, and ratio were evaluated. Results: The postoperative volume reduction was significant for both groups when compared with 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 versus 364.27 ± 364.08 cm³, 6.13 ± 5.62% versus 8.77 ± 6.64%; P < 0.05) and 3 months (289.19 ± 291.42 cm³ versus 432.50 ± 395.04 cm³, 7.31 ± 6.39% versus 10.55 ± 6.88%; P < 0.05) However, the reduction volume and ratio was not significant by months 6 and 12. Conclusions: This study provides further insight into 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.