经肛门直肠黏膜及内括约肌切除术治疗先天性巨结肠的技术要点和疗效

目的 探讨肛门内括约肌大部切除对治疗小儿先天性巨结肠的技术可行性和临床效果.方法 从2001年7月至2006年12月,对127例先天性巨结肠患儿根治术中进行内括约肌大部切除,手术时患儿年龄8 d～16岁,平均年龄0.96岁,小于3个月的33例,其中新生儿12例.术前43例(33.8%)有肠炎病史,手术方法:在齿线水平的直肠黏膜与肛管皮肤的交界处环周切开黏膜及肛门内括约肌;沿内、外括约肌之间隙向盆腔侧分离1cm后;在前壁切开直肠的肌层至黏膜下层,沿着黏膜下层向上分离直达腹膜返折水平切开肌鞘,入腹腔;在后壁沿着直肠纵肌,一直向上分离至相应的腹膜返折水平.将正常结肠拖出至肛缘水平与肛管黏膜皮肤相吻合.结果 本组127例患儿均经肛门行内括约肌和直肠后壁肌鞘切除术,目前106例患儿术后已随访1至7年,术后仅2例患儿有肠炎病史,术后肠炎发生率为1.8%,比术前明显减少(P<0.01).3例(2.7%)患儿手术后便秘,1例在外院确诊为结肠神经元发育不良症,行结肠切除手术后治愈.手术后1个月时污便的发生率37.6%,随手术后时间的延长,手术后6个月时污便下降至1.8%.肛门直肠测压结果显示:对照组肛管静息压力为(27.9±9.6)mm Hg;先天性巨结肠患儿手术前的肛管静息压力为(37.9±12.5)mm Hg,比对照组明显增高(P<0.05);手术后1、2、3、6个月肛管静息压力分别为(20.2±6.4)、(21.4±8.8)、(22.8±10.4)、(24.8±9.9)mm Hg,手术后肛管静息压力比手术前明显减低(P<0.01),术后6个月内患儿的肛管静息压力有上升的趋势,与对照组差异无统计学意义.结论 本研究结果表明经肛门内括约肌大部切除安全易行,可有效地预防小儿先天性巨结肠术后肠炎和便秘的发生.

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.