LAUSR

Dear Sirs, Lymphedema is the chronic, progressive swelling of tissue from deposition of fluid, adipose, and fibrosis caused by lymphatic dysfunction. Lymphatic-venous anastomosis (LVA) is a surgical treatment that establishes subdermal lymphatic and venular connections in the affected limb to improve lymphedema (Chang, Suami, & Skoracki, 2013). Finding these sub-millimeter structures in the enlarged extremity can be difficult. Vein illumination, isosulfan blue, or indocyanine green (ICG) have been described as useful adjuncts for lymphatic or sentinel node procedures; the concomitant use of all three tools for LVA previously has not been reported (Chang et al., 2013; Liu, Truini, & Ariyan, 2008; Mihara et al., 2012). The purpose of this letter is to describe our standardized method for LVA using vein illumination, isosulfan blue, and ICG to optimize placement of incisions and enhance lymphatic visualization at each site. Patients with International Society of Lymphology (ISL) stages I–II lymphedema with delayed lymphatic transit on preoperative ICG lymphangiography or lymphoscintigraphy are offered LVA (Hannah et al., in press). Those with complete lymphatic obstruction are considered for vascularized lymph node transfer instead of LVA. In the preoperative area, the patient’s superficial veins on the affected limb are visualized using non-contact transcutaneous vein illumination (AccuVein AV400; Avant Medical, Cold Spring Harbor, NY) and marked (Figure 1). In the operating room, ICG is injected in the webspaces of the extremity (0.2 mL of 2.5 mg/mL) and the subdermal lymphatics are mapped with fluorescence lymphangiography and marked (SPY Elite; Novadaq Technologies Inc., Mississauga, Ontario, Canada). The locations of the incisions are chosen in areas with adjacent vein and lymphatic skin markings. Isosulfan blue (Lymphazurin 1%; Hirsch Industries Inc, Richmond, VA) is injected intradermally (0.2 mL) 2 cm distal to each incision site. Lymphatic vessels (blue-appearing because of isosulfan) and veins are dissected under the microscope and anastomosed using 11–0 nylon suture. Lymphatics and veins ideally should be in close proximity because they risk injury if extensive mobilization is necessary to create the anastomosis. Transcutaneous vein illumination, ICG lymphatic mapping, and isosulfan blue maximize the ability to identify adjacent lymphatics and veins. Transcutaneous vein illumination commonly is used by nurses and anesthesiologists for peripheral intravenous cannulation (de Graaff et al., 2013). The commercially available system uses a near-infrared laser that is absorbed by hemoglobin. This handheld, non-contact device causes veins to appear dark on a background of illuminated skin. ICG lymphangiography has been used to assess lymphatic function, characterize dermal backflow patterns, and as an adjunct for LVA (Chang et al., 2013; Mihara et al., 2012). ICG is absorbed in the lymphatics when injected subcutaneously; a near-infrared laser camera captures ICG fluorescence allowing for mapping of the subdermal lymphatics to a 2 cm depth. Assessing the superficial veins with transcutaneous vein illumination and mapping the subdermal lymphatics with