Becker J M, LaMorte W, St Marie G, Ferzoco S
Department of Surgery, Boston University School of Medicine, Massachusetts, USA.
Dis Colon Rectum. 1997 Jun;40(6):653-60. doi: 10.1007/BF02140893.
In patients undergoing colectomy with ileal pouch-anal anastomosis, controversy exists regarding the necessity for and appropriate extent of rectal mucosal resection. Our aim was to assess histologically the extent of anorectal smooth muscle resected at the time of mucosal proctectomy and to correlate this with postoperative bowel and anal sphincter function.
Surgical specimens of 79 patients undergoing colectomy, mucosal proctectomy, and ileal pouch-anal anastomosis were examined histologically in a blinded fashion, and the content of smooth muscle in the mucosal proctectomy specimens was scored. Degree of smooth muscle resection was correlated with postoperative anorectal manometry and with functional outcomes, including stool frequency and nocturnal leakage of stool after 3 and 12 months of follow-up.
Degree of smooth muscle loss correlated with decreased resting pressure of the internal anal sphincter as early as three months after surgery (r = -0.26; P = 0.03), and the correlation was even stronger after 12 months (r = -0.37; P = 0.005). Decreases in resting pressure were related, in turn, to increased stool frequency at 12 months (r = 0.32; P = 0.02), but stool frequency was also inversely related to volume of the ileal pouch (r = -0.27; P = 0.05). Multivariate analysis confirmed that resting pressure and pouch volume were both significant determinants of stool frequency. The likelihood of nocturnal stool leakage at 12 months was primarily a function of stool frequency (P < 0.01) but also increased with patient age (P < 0.02).
These findings indicate that loss of resting pressure of the internal anal sphincter can be correlated with the extent of smooth muscle resection during rectal mucosectomy and that these factors, in turn, correlate with increased stool frequency and a greater likelihood of nocturnal stool leakage. Consequently, an optimum functional result requires care in identifying and preserving maximum anorectal smooth muscle during mucosectomy.
在接受结肠切除术并进行回肠储袋肛管吻合术的患者中，对于直肠黏膜切除的必要性和适当范围存在争议。我们的目的是通过组织学评估黏膜直肠切除术时切除的肛门直肠平滑肌的范围，并将其与术后肠道和肛门括约肌功能相关联。
对79例接受结肠切除术、黏膜直肠切除术和回肠储袋肛管吻合术的患者的手术标本进行盲法组织学检查，并对黏膜直肠切除标本中的平滑肌含量进行评分。平滑肌切除程度与术后肛门直肠测压以及功能结果相关，包括随访3个月和12个月后的排便频率和夜间大便失禁情况。
早在术后3个月，平滑肌丢失程度就与肛门内括约肌静息压力降低相关（r = -0.26；P = 0.03），12个月后相关性更强（r = -0.37；P = 0.005）。静息压力降低反过来又与12个月时排便频率增加相关（r = 0.32；P = 0.02），但排便频率也与回肠储袋容积呈负相关（r = -0.27；P = 0.05）。多因素分析证实，静息压力和储袋容积都是排便频率的重要决定因素。12个月时夜间大便失禁的可能性主要取决于排便频率（P < 0.01），但也随患者年龄增加而增加（P < 0.02）。
这些发现表明，肛门内括约肌静息压力的丧失与直肠黏膜切除术中平滑肌切除的范围相关，而这些因素又与排便频率增加和夜间大便失禁的可能性增加相关。因此，要获得最佳功能结果需要在黏膜切除术中小心识别并保留最大量的肛门直肠平滑肌。
