Uterus autotransplantation in cynomolgus macaques: Intraoperative evaluation of uterine blood flow using indocyanine green

Background Uterus transplantation may be the only theoretical option for some women, for example, those with congenital uterine infertility or who have undergone hysterectomy. In this study, we evaluated the intra-and post-operative blood flow conditions of vascular anastomosed regions and the blood-perfused area of the transplanted uterus in a cynomolgus macaque model of uterus autotransplantation. Methods Female cynomolgus monkeys (n = 6) underwent surgery: the first two animals were used to study the pelvic vascular anatomy and the remaining four animals were used for uterus autotransplantation. We used indocyanine green (ICG) fluorescent angiography during surgery to assess blood perfusion in the vascular anastomosed region and uterine area. After surgery, the uterine size, presence or absence of the endometrium and blood flow rates in the uterine artery and vein were evaluated using Doppler ultrasonography. Results Uterine arterial and venous anastomoses succeeded in all four animals that underwent autotransplantation. Intraoperative ICG fluorescence angiography showed favorable blood flow in the vascular anastomosed regions and the entire uterus received a sufficient blood supply from a single uterine artery. Favorable blood flow in the uterine artery and vein immediately after surgery was shown by Doppler ultrasonography. Ultimately, three out of four animals died within 3 months following surgery because of reduced feeding and loss of body strength. Conclusions ICG fluorescence angiography can be used for simple evaluation of real-time blood flow conditions in the anastomosed uterine artery, vein and uterine area and can facilitate the success rate of uterus transplantation.