Objective To compare the safety and effectiveness of two methods of perineal dissection in 60 consecutive patients of rectal carcinoma undergoing combined abdominoperineal resection.Methods In this retrospective study from 2007 to 2009, 30 cases underwent Miles' operation using modified method of perineal dissection( MM group) and 30 cases undergoing Miles' operation using classic method of perineal dissection ( CM group). Operative time, accidental tumor ( or rectal) perforation during the procedure, iatrogenic injury to the urethra ( or vagina) and postoperative perineal complications were compared between the two groups. Results The mean perineal operative time was (45±15) min in MM group and ( 70 ± 20) min in CM group respectively ( t = 5. 48, P ＜ 0. 05 ). There were no significant differences in the rate of tumor ( or rectal) perforation and that of urethral (vaginal) injury. There were significant difference in the rate of postoperative perineal complications (χ2=4.01, P＜0.05).Conclusions Modified method of perineal dissection is effective and safe, and this method offers a new approach for the perineal dissection during Miles' operation.

Objective To study the anatomy of pelvic autonomic nerves, to avoid autonomic nerves damage during rectal cancer surgery. MethodsAnatomical dissections were carried out on 7 adult cadavers, and clinically autonomic nerve-preserving rectal cancer resection was performed. Results The superior hypogastric plexus lies just posterior to the inferior mesenteric vessels. There were no obvious autonomic nerve trunks in the loose areolar tissue plane between the parietal fascia and the visceral fascia right posterior to the rectum. There were no obvious autonomic nerve trunks between the rectum and the seminal vesicles or the prostate. The inferior hypogastric plexus was a rhomboid shaped plaque of nervous tissue. The main components of the lateral ligament were autonomic nerves passing from the pelvic plexus to the rectum within a condensation of connective tissue. WT5”HZConclusionsThe inferior mesenteric vessels can be used a landmark intraoperatively to identify the superior hypogastric plexus. In order to preserve the inferior hypogastric plexus while dissecting the lateral of rectum, we should dissect along the medial surface of the inferior hypogastric plexus, and along its curvature. JP2