The Venous Lymph Node Flap: Concepts, Experimental Evidence, and Potential Clinical Implications

Background Traditionally, lymph node flaps (LNF) have been designed as arteriovenous flaps, with little attention given to the functional anatomy of lymphatic system included in the flap. Based on the anatomical and physiological features of lymphatic system, we believe that a new concept of LNF, the venous LNF, should be investigated. In this article, we report the concepts and findings of venous LNF, and help gauge its potential clinical application in the treatment of lymphedema. Methods Eight healthy Wistar rats underwent cervical LNF harvesting along the right external jugular vein, right inguinal node clearance, and venous LNF transfer in a flow-through fashion along the femoral vein. At 45 postoperative days, the restoration of lymphatic continuity with surrounding tissue was verified with intradermal injection of 0.1% of methylene blue. The flaps were then excised and sent for histologic evaluation. Results All rats survived uneventfully in the postoperative period and no postoperative complications were experienced. The venous anastomosis was proven to be patent clinically. In all rats we found reestablishment of lymphatic continuity with surrounding tissues. Histologically, the nodes showed the following main histoarchitectural changes: drastic reduction of the stromal compartment and preservation of the lymphatic/sinus and vascular compartments. Conclusions The novel venous LNF flap is able to restore lymphatic continuity with surrounding tissue. As healing occurs, the lymph nodes undergo major histoarchitectural changes. The venous LNF has unique theoretical advantages over arteriovenous LNFs. Further investigations would be beneficial to understand its potential in the surgical treatment of lymphedema.