Lower uterine blood supply:: extrauterine anastomotic system and its application in surgical devascularization techniques

Background. To establish the arterial components that determine lower uterine blood supply, varieties and anastomoses that result in complications during selective devascularization procedures. Methods. Thirty-nine female cadaveric pelvises with latex repletion in pelvic arteries were used. All the material was studied through direct dissection, and dissection enlarged with a 90-diopter magnifying glass, establishing origin, course, and anastomoses of the genital arteries. Axial calibers of the uterine and the main vaginal arteries were compared. An anatomical and a historical compilation of the uterine artery was made, with special reference to anastomotic areas in the lower sector. Results. Three main pedicles were determined in the lower uterine blood supply: a cephalic one constituted by the uterine artery, a medial one made up by the cervical artery, and a distal one formed by the vaginal arteries. Different types of anastomoses were distinguished among the upper, middle, and lower pedicles. All types of anastomoses displayed similar features and were interconnected along the isthmic-vaginal borders, or as an intramural anastomotic network. In many cases, a transmedial interuterine anastomosis of axial caliber equivalent to the uterine artery itself could be observed. The bibliography consulted provided neither detailed descriptions of the cervical-segmental arterial system nor of the vaginal system or its anastomoses. In two cases, images were found in books that show this anastomotic system without further explanation. Conclusion. A not very well known anastomotic system was described between uterine and vaginal arteries. This system explains some reported failures, complications, and hemodynamic changes after uterine devascularization procedures.