Nerve-preserving rectal surgery: results of a study on human cadavers and formalin-fixed human pelvises

Introduction: Preservation of sexual function and voiding capacity after re ctal cancer surgery has increased after adopting the technique of nerve-spa ring dissection and total mesorectal excision. Still the rate of sexual and urinary dysfunction ranges between 25 and 67%. The precise locations where nerve damage occurs have not been looked at systematically. Material ann m ethods: In ten human corpses and two formalin fixed human pelvises the auto nomous pelvic nerves were isolated. Their relation according to surgical mo bilization of the rectum were photodocumented. Results: Pelvic autonomous n erves are clearly defined structures with only minor interindividual variab ility. The inferior mesenteric plexus forms a dense network around the infe rior mesenteric artery (AMI) to a distance of 5 cm from the aorta. The dist ance between the lateral rectum and the pelvic plexus is only 2-3 mm. The a nterior rectum is almost directly adherent to the neurovascular bundle, sep arated only by Denonvillier's fascia. The parasympathetic branches of the s acral segments S2-S5 cannot be isolated using the standard surgical approac h. Conclusion: (1) The nomenclature of fascias and the course of the autono mous pelvic nerves is not clearly defined in the literature; (2) a high tie of the AMI leads to damage of the sympathetic nerves; (3) the narrow space between the anterior and lateral rectum makes sharp dissection under direc t vision necessary; (4) fascias and nerves can be used as guiding structure s during mobilization; (5) a preservation of selected parasympathetic roots in the small pelvis is not feasible using the standard surgical approach.