Sultan A H, Kamm M A, Nicholls R J, Bartram C I
Department of Physiology, St. Mark's Hospital, London, United Kingdom.
Dis Colon Rectum. 1994 Oct;37(10):1031-3. doi: 10.1007/BF02049319.
The aim of lateral internal anal sphincterotomy when treating anal fissure is to divide the distal one-third to one-half of the internal anal sphincter. This study aimed to evaluate prospectively the extent of disruption to the internal anal sphincter following lateral anal internal sphincterotomy and also to establish the prevalence of symptoms of anal incontinence in these patients.
Fifteen patients with anal fissure (ten females and five males) had bowel symptoms assessed and anal endosonography performed preoperatively and two months after lateral internal anal sphincterotomy.
Anal endosonography was normal preoperatively in all but two females who had anterior external sphincter defects (presumedly from previous obstetric trauma). Postoperatively, apart from one male in whom no defect could be identified, all had an internal anal sphincter defect corresponding to the site of lateral internal anal sphincterotomy. In nine of the ten females, the defect involved the full length of the internal anal sphincter, but in the other four males, the defect involved the distal internal anal sphincter only. All were continent preoperatively, but after lateral internal anal sphincterotomy, three females became incontinent to flatus (two of whom had a preoperative external sphincter defect).
In contrast to lateral internal anal sphincterotomy in males, division of the internal anal sphincter in most females tends to be more extensive than intended. This is probably related to their shorter anal canal. In some females, lateral internal anal sphincterotomy may compromise sphincter function and precipitate anal incontinence, particularly in the presence of other sphincter defects. Care should be exercised especially in the presence of previous obstetric trauma, as internal anal sphincter division may further compromise sphincter function.
治疗肛裂时行侧方内括约肌切开术的目的是切断肛管内括约肌远侧三分之一至二分之一。本研究旨在前瞻性评估侧方内括约肌切开术后内括约肌的破坏程度，并确定这些患者中肛门失禁症状的发生率。
15例肛裂患者（10例女性，5例男性）在侧方内括约肌切开术前及术后2个月进行肠道症状评估和肛门腔内超声检查。
除2例有前外侧括约肌缺陷（推测为既往产科创伤所致）的女性外，术前所有患者的肛门腔内超声检查均正常。术后，除1例未发现缺陷的男性外，所有患者均有与侧方内括约肌切开部位相对应的内括约肌缺陷。10例女性中有9例，内括约肌缺陷累及全长，但在其他4例男性中，缺陷仅累及内括约肌远侧部分。所有患者术前均能控制排便，但侧方内括约肌切开术后，3例女性出现排气失禁（其中2例术前有外括约肌缺陷）。
与男性侧方内括约肌切开术不同，大多数女性内括约肌的切断范围往往比预期的更广泛。这可能与她们较短的肛管有关。在一些女性中，侧方内括约肌切开术可能会损害括约肌功能并导致肛门失禁，尤其是在存在其他括约肌缺陷的情况下。特别是在有既往产科创伤的情况下应格外小心，因为切断内括约肌可能会进一步损害括约肌功能。
