[The surgical anatomy of the genital nerves of the male and their preservation in excision of the rectum].

Studies of the fetus and new-born were undertaken to determine the exact localization of the nn. erigentes in the lower pelvis. The particular topography was visualized using histological slides and a special digital imaging technique. The nn. erigentes were found to be bundled along the diaphragmatic part of the urethra before entering the two cavernous bodies of the penis. These findings suggest that a small anterior patch of rectal muscle covering the diaphragmatic part of the urethra should be left behind in male patients undergoing total proctocolectomy in order to preserve potency. This operative technique cannot be employed for carcinomas extending to the anterior rectal wall. Since 1980, the new technique has been used in 18 male patients with rectal carcinoma and sexual function was preserved in all cases.