Lymphatic reconstruction with vascularized lymph vessel flap: lymph-interpositional-flap transfer

Abstract

Lymph node transfer (LNT) and lymphatic anastomosis are popular reconstructive surgeries in managing lymphedema. However, lymphatic anastomosis requires the operator to be adept at super microsurgery, and LNT has significant donor-site lymphedema risks. To address these drawbacks, lymph-interpositional-flap transfer (LIFT), a novel lymphatic reconstruction method that does not require lymph node transfers or supermicrosurgical techniques, has been introduced. Lymph circulation after tissue replantation and free flap transfer was evaluated using indocyanine green (ICG) lymphography. Postoperative ICG lymphography showed linear to linear lymphatic reconnection between an amputee/flap and a recipient site in cases where the stumps of the lymph vessels were only approximated. This was a frequent phenomenon observed in replantation cases and some free tissue transfers. Based on these results, we developed a new lymphatic reconstruction using a flap designed to include the collecting lymph vessels for bridging a lymphatic gap. ICG is injected at the peripheries of donor sites or the distal boundaries of the lymphosome where the recipient site resides in. This allows us to visualize the axial lymphatic pathways. When LIFT is used to reconstruct a soft tissue defect, ICG is also injected at the proximal edge of it to visualize proximal lymph flows. The LIFT flap is designed to include lymphatic channels seen on pre-operative ICG lymphography. As these collecting lymph vessels reside deep in the superficial fascia, the flap is elevated with the deep fat intact. Intra-operative ICG lymphography is utilized to identify the proximal and distal lymphatic stumps on the flap, and absorbable sutures are used to tag these stumps for ease of recognition during the flap inset. LIFT is indicated for soft tissue defects in major lymphosomes, resulting in a significant lymphatic gap. The advantage of the LIFT technique is the ability to perform simultaneous soft tissue and lymphatic reconstruction. LIFT can also be applied in established lymphedema and elephantiasis.