Comparison of Lymphovenous Shunt Methods in a Rat Model: Supermicrosurgical Lymphaticovenular Anastomosis versus Microsurgical Lymphaticovenous Implantation

Background: Lymphaticovenular anastomosis and lymphaticovenous implantation are the most popular lymphovenous shunt operations for the treatment of obstructive lymphedema. However, no study has been reported regarding direct comparison between lymphaticovenular anastomosis and lymphaticovenous implantation. This study aimed to compare postoperative patency of lymphaticovenular anastomosis and lymphaticovenous implantation using a rat model. Methods: Twelve Wistar rats were used for the study. The rats were randomized into the lymphaticovenular anastomosis group ( n = 6) or the lymphaticovenous implantation group ( n = 6). In the lymphaticovenular anastomosis group, the largest femoral lymphatic vessel was anastomosed to a similar-size vein in an end-to-end intima-to-intima coaptation manner, and the other lymphatics were ligated. In the lymphaticovenous implantation group, the femoral lymphatic vessel and surrounding tissue were inserted into the short saphenous vein with a telescopic anastomosis technique. Patency was evaluated intraoperatively and 1 week postoperatively with patent blue dye and indocyanine green lymphography. Results: The mean diameters of the lymphatic vessels and the veins were 0.242 mm (range, 0.20 to 0.35 mm) and 0.471 mm (range, 0.30 to 0.75 mm), respectively. Intraoperative patency was 100 percent (six of six) in both groups ( p = 1.000). Postoperative patency was significantly higher in the lymphaticovenular anastomosis group compared with the lymphaticovenous implantation group [100 percent (six of six) versus 33.3 percent (two of six); p = 0.014] Conclusion: Postoperative patency of the lymphaticovenular anastomosis group was higher than that of the lymphaticovenous implantation group, although intraoperative patency rates of the lymphaticovenular anastomosis and lymphaticovenous implantation groups were comparable.