Pelvic autonomic nerve preservation in radical rectal cancer surgery: changes in the past 3 decades

Abstract

The advent of total mesorectal excision (TME) together with minimally invasive techniques such as laparoscopic colorectal surgery and robotic surgery has improved surgical results. However, the incidence of bladder and sexual dysfunction remains high. This may be particularly distressing for the patient and troublesome to manage for the surgeon when it does occur. The increased use of neoadjuvant and adjuvant radiotherapy is also associated with poorer functional outcomes. In this review, we evaluate current understanding of the anatomy of pelvic nerves which are divided into the areas of the inferior mesenteric artery pedicle, the lateral pelvic wall and dissection around the urogenital organs. Surgical techniques in these areas are discussed. We also discuss the results in functional outcomes of the various techniques including open, laparoscopic and robotic over the last 30 years.

Keywords: pelvic autonomic nerve preservation; sexual dysfunction; total mesorectal excision; urinary dysfunction.

Figure 1

General overview of anatomy of the autonomic nerve distribution. The superior hypogastric plexus around the inferior mesenteric artery descends to the sacral promnotry and bifurcates into hypogastric nerves. These usually run 1–2 cm medial to the ureters and cross the common iliac arteries and S1 in the sacrum.

Figure 2

Inferior hypogastric nerve with branches to the rectum on a robotic view with medial-to-lateral dissection approach.

Figure 3

Anatomy of the pelvic autonomic nerves with relation to rectum. The inferior hypogastric plexus comprises nerves from the hypogastric and pelvic splanchnic nerves at lateral pelvic wall.

Figure 4

The relationship of the rectum and pelvic autonomic nerves during open surgery when standing on the patient’s left. The ligation of the inferior mesenteric artery should be performed 1.5–2 cm from its origin from the aorta to avoid damaging the superior hypogastric plexus. At the pelvis, for posterior and lateral tumours, dissection should be directed below the Denonvillliers fascia to avoid damaging the neurovascular bundles that run along the tip of the seminal vesicle (2 and 10 o’clock directions).