Effective and efficient lymphaticovenular anastomosis using preoperative ultrasound detection technique of lymphatic vessels in lower extremity lymphedema

Background Identification of functional lymphatic vessels and localization of lymphatic vessels are important for lymphaticovenular anastomosis (LVA). Indocyanine green (ICG) lymphography is useful for localization of superficial lymphatic vessels where dermal backflow is not observed, but not for lymphatic vessels in deep layer or where dermal backflow is observed. Ultrasound has been applied in LVA and is considered useful for localization of lymphatic vessels with ICG lymphography cannot be visualized. Methods Fifty‐five secondary lower extremity lymphedema (LEL) patients who underwent LVA were classified into two groups, ultrasound‐detection‐of‐lymphatic group (US group, n = 29) and non‐ultrasound‐detection‐of‐lymphatic group (non‐US group, n = 26), and assessed. Sensitivity and specificity to detect lymphatic vessel were evaluated in US group. Intraoperative findings, required time for dissecting lymphatic vessels and veins, length of skin incision, and postoperative lymphedematous volume reduction were compared between the groups. Results Lymphatic vessels were detected in all incisions in both groups. LVA resulted in 232 anastomoses in US group and 210 anastomoses in non‐US group. Sensitivity and specificity of ultrasound for detection of lymphatic vessels were 88.2% and 92.7%, respectively. Diameter of lymphatic vessels found in US group was significantly larger than that in non‐US group (0.66 ± 0.18 vs 0.45 ± 0.20 mm; P = 0.042). Time required for dissecting lymphatic vessels and veins in US group was shorter than that in non‐US group (9.2 ± 1.7 vs 14.7 ± 2.4 min; P = 0.026). LEL index reduction was significantly greater in US group than that in non‐US group (26.7 ± 13.6 vs 7.8 ± 11.3; P = 0.031). Conclusions Ultrasound‐guided detection of lymphatic vessels for lymphedema was performed with high precision, and allows easier and more effective LVA surgery.