Lymphaticovenous anastomosis in rabbits: A novel live experimental animal model for supermicrosurgical training

Background Lymphaticovenous anastomosis is widely used in lymphedema management. Although its effectiveness in reducing edema in patients can be clinically observed, evaluating the long-term outcomes of this technique can be complex. This study established an animal model to assess the lymphaticovenous anastomosis technique at 15- and 30-days post-surgery, utilizing indocyanine green lymphography, Patent Blue V, and histopathological examination. Methods An experimental model was established in the hindlimbs of ten rabbits using the popliteal vein and afferent lymphatic vessels in the popliteal area. The subjects were divided into two groups: the first (n=5) underwent patency assessment at 0 and 15 days, and the second (n=5) at 0 and 30 days, resulting in 20 anastomoses. Patency was verified at 0, 15, and 30 days using indocyanine green and Patent Blue V. Histopathological examinations were performed on the collected anastomosis samples. Results The patency rate was 90% (19/20) initially, 60% (6/10) at 15 days post-surgery, and 80% (8/10) at 30 days. The average diameter of lymphatic vessels and veins was 1.0mm and 0.8mm, respectively. The median number of collateral veins was three; the median surgical time was 65.8min. Histopathology revealed minimal endothelial damage and inflammatory responses due to the surgical sutures, with vascular inflammation and thrombosis in a single case. Local vascular neoformations were observed. Conclusion This study highlights the reliability and reproducibility of rabbits as an experimental model for training in lymphaticovenous anastomosis technique due to the accessibility of the surgical site and the dimensions of their popliteal vasculature.