Rectal mucosectomy and internal anal sphincterectomy for children with Hirschsprung's disease

Objective To investigate the feasibility of rectal mucosectomy and internal anal sphineterectomy (IAS) procedure for Hirschsprung's disease (HD) to prevent postoperative HD-re-lated enterocolitis. Methods This study was carried out on 127 patients with HD. Their age ranged from 8 d to 16 years (mean 0. 96 yrs), and 33 cases were younger than three months, twelve of them were newborns. Forty-three patients (33.8%) had episodes of HD related enterocolitis before the op-eration. Mucosectomy and IAS were started circumferentially at the junction between rectal mucosa and anal cutaneous mucosa (the dental line). The dissection was started between the internal anal sphincter and the external anal sphincter. Between 1.0 cm up to the incision and the peritoneal reflection, anterior dissection was made along the rectal submucosal layer with the rectal muscular sleeve intact. The posterior dissection was made steadily along the rectal muscular wall up to the pelvic. The normal colon was pull-through and anatomized to the anal mucosa. In this way, the rectal mucosa, the most majority of internal sphincter and rectal muscular cuff were removed. Results Mucosectomy and IAS were successfully undertaken in 127 patients. The patients were followed up for 1 to 7 years. Two cases had episodes of HD-related enteroclitis and the incidence of enteroeolitis (2/106, 1.8%) was significantly lower than that before the operation (P<0.01). Three cases (1/106, 2.7%) suffered from postoperative constipation, and one case was diagnosed as total colon intestinal neuronal dysplasia and cured by colectomy. One month after the operation, 37.6% patients had soiling, however it gradually decreased to 1.8% at the 6th month after the operation. Anorectal manometery examination showed that the anal resting pressures in control group were significantly lower than in HD group (27.9±9.6 mm Hg vs 37.9±12.5 mm Hg, P<0.05). Postoperatively, the resting pressures in 1st, 2nd, 3rd and 6th month were 20.2±6.4 mm Hg,21.4±8.8 mm Hg,22.8±10.4 mm Hg, and 24.8±9.9 mm Hg, respectively. There was no significant difference in the resting pressures between the control group and the patients in the 6th month (P0.05). Conclusions Rectal mucosectomy and IAS are safe and effective to prevent postoperative HD-related enterocolitis and constipation. Key words: Hirschsprung's disease;  Enteritis;  Anal canal