Efficacy validation of a lymphatic drainage device for lymphedema drainage in a rat model

Background: Vascularized lymph node transfer (VLNT) is an effective surgery for extremity lymphedema. This study evaluated a lymphatic drainage device (LDD) for the drainage of accumulated fluid into the venous system. Methods: Micropore filtering membranes with pore sizes of 5, 0.65, and 0.22 μm polyvinylidene difluoride, and 0.8 μm Nylon Net Filter were evaluated to determine the in vitro efficiency of drainage flow of an LDD. The two superior membranes were further used for the evaluation of the inflow and outflow of the LDD in vivo using 5% albumin. Results: At 5 minutes, the volumes drained with 5, 0.65, and 0.22 μm polyvinylidene difluoride and 0.8 μm nylon membranes were 15.2, 2.77, 2.37, and 0.59 mL, respectively (P <.01). At 10 minutes, the collected volumes of 5 and 0.65 μm polyvinylidene difluoride were 1788 and 1051 μL (P =.3). The indocyanine green fluorescence was detected at 50 seconds for the 5 μm polyvinylidene difluoride membrane but not for the 0.65 μm membrane. Conclusions: The study successfully demonstrated the proof-of-concept of the LDD prototype that mimicked VLNT with drainage of 5% albumin into the venous system in a rat model.