[Lympho-reconstructive microsurgery for secondary lymphedema: Consensus of the German-Speaking Society for Microsurgery of Peripheral Nerves and Vessels (DAM) on indication, diagnostic and therapy by lymphovenous anastomosis (LVA) and vascularized lymph node transfer (VLNT)].

Secondary lymphedema is a complex and devastating disease including chronic inflammation and reduced immunofunction, lymphatic fluid and protein accumulation due to misdirected lymphatic transport, and secondary fat deposition followed by fibrosis. While the domain of treatment still is lifelong complex decongestive therapy, it is more and more widespread to treat the disease with a surgical focus on physiologic, reconstructive strategies or debulking surgery. Lymphovenous Anastomosis (LVA) and Vascularized lymph node transplantation (VLNT) are the mostly frequently applied, reconstructive techniques which address restoration or improvement of physiologic lymph clearance. The article summarizes and discusses the recommendations of an expert panel on the diagnostic, indication and therapy of LVA and VLNT in secondary lymphedema during the 40 Meeting of the Germanspeaking Society of Microsurgery in Lugano, Switzerland, 2018. The expert panel addressed the basic diagnostics prior to lymphoreconstructive surgery, including the inevitable application of Indocyanine Green (ICG) based fluorescence lymphangiography and navigation for both techniques including reverse mapping to reduce the rate of donor-site lymphedema for VLNT as well as the use of lymphedema-specific quality of life questionnaires. Both LVA and VLNT are elaborately described, including tips and tricks on identifying functional lymphatic collectors, equipment, types of anastomosis and documentation for LVA and choice of donor and recipient site, number of includable lymph nodes and management of specific donor sites, e. g. jejunal mesenteric for VLNT. The synchronous and sequential application of LVA, VLNT and/or ablative liposuction is discussed against the background of the effectivity and morbidity of both reconstructive, physiologic techniques. Finally, recommendations on post-operative treatment and diagnostics are discussed. The present consensus paper intends to improve the level of standardization for further multicenter studies in the germanspeaking countries in this aspiring field of lymphedema treatment.