To explore the application effect of methylene blue lymphangiography combined with indocyanine green angiography for the preoperative localization of lymphatic vessels in lymphaticovenular anastomosis (LVA).

Fifty-three cases of lower extremity lymphedema patients underwent LVA in the Department of Burn, Plastic and Cosmetic Surgery of Xi′an Central Hospital, Xi′an Jiaotong University from February 2021 to May 2023 were selected. The patients were divided into control group (24 cases) and study group (29 cases), according to different methods for preoperative lymphatic vessel localization in LVA. The control group used traditional methylene blue lymphangiography, while the study group used methylene blue lymphangiography combined with indocyanine green angiography for preoperative lymphatic vessel localization.Observed internal methylene blue staining, lymphatic vessel identification time, operation time, the number of anastomosed lymphatics per incision, extra-lymphatic blue contamination, epidermal ulceration of the patients. Lower extremity lymphedema index (LELI) and lymphoedema functioning, disability and health questionnaire for lower limb lymphoedema (Lymph-ICF-LL) before and 3, 6 months after operation were compared between the two groups.

The lymphatic vessel identification time [14 (8, 22) min] and the operative time [(185.93 ± 33.43) min] in the study group were both shorter than those in the control group [20 (13, 30) min, (217.00 ± 59.19) min], and the differences were statistically significant (Z=-3.592, P<0.001; t=2.404, P=0.020). The success rate of methylene blue staining in the study group (65.52%) was higher than that in the control group (46.88%), and the proportion of extra-lymphatic blue contamination (4.31%) was lower than that in the control group (13.54%), with statistically significant differences (χ²=7.451, 5.761; P=0.006, 0.016). There was no statistically significant difference in the number of anastomosed lymphatics per incision between the two groups (Z=-1.757, P=0.079). The LELI(F=112.889, 136.113; P<0.001) and Lymph-ICF-LL scores (F=71.956, 113.342; P<0.001) were significantly reduced in both groups at 3 and 6 months after surgery compared to preoperative, and the prognosis improved.

Methylene blue lymphangiography combined with indocyanine green angiography used in LVA for the preoperative localization of lymphatic vessels, can make methylene blue staining of lymphatic vessels more accurate and shorten the lymphatic vessel identification time and operation time.