Extrafascial excision of the rectum - Surgical anatomy of the fascia propria

PURPOSE: It is now agreed that it is of vital importance to maintain the fa scia propria as an intact envelope around the mesorectum to prevent tumor s pillage while performing rectal excision for cancer. There are several surg ical techniques described to achieve an intact fascial envelope, each arisi ng from differing descriptions of the fascia propria of the rectum. The aim of this study was to describe the detailed surgical anatomy of the fascia propria. METHODS: Thirteen rectal specimens surgically removed by the techn ique of extrafascial excision a ere subjected to gross inspection, dissecti on, and histologic and electron microscopic examination. The attachments, t hickness, and composition of the fascia propria were determined. RESULTS: T he fascia propria is a continuous fascial sleeve surrounding the rectum and mesorectum that can be dissected as a complete "sock" off a fresh extrafas cial specimen. It is 154 (+/- 1 standard deviation = 61-391) mu m thick, is thinner anteriorly than posteriorly (P < 0.05), and is composed predominan tly of collagen. It can be identified surgically at the pelvic brim as a sh iny membrane and lies inside the hypogastric nerves and the pelvic plexuses . CONCLUSION: The fascia propria forms a sleeve around the mesorectum, offe ring a surface against which to dissect, enabling safe removal of the rectu m with its intact mesorectum while preserving the autonomic nerves of the p elvis. The term "extrafascial excision" highlights the importance of the fa scia propria in this operation.