肛管括约肌压力偏位产生的解剖学基础及其临床意义

The anatomic evidence and clinical usage of the manometric asymmetry of the anal sphincter

目的探寻肛管内不同层面各个方向括约肌压力偏位(非对称性)形成的解剖学基础及其临床意义。方法采用CTD-SYNECTICS公司生产的高分辨多通道胃肠功能测定仪对27例正常儿童及12例肛门失禁患儿进行肛门括约肌压力检测,对距离肛门缘6cm范围内每间隔0.5cm的直肠肛管各层面进行8个方向的纵向及横向的压力测量,观察8个方向不同层面纵向压力梯度变化及横向压力偏位方向的梯度变化。结果正常儿童静息及收缩状态下,肛管8个方向均存在括约肌压力的纵向梯度变化,于距离肛门缘1cm层面形成压力的最大值;距离肛门缘3cm到2cm到1cm均存在括约肌压力偏位方向的梯度变化,即存在肛管后方高压向前方高压的转变;距离肛门缘1cm层面于肛管前方形成压力的最大值。肛门失禁患儿在静息及收缩状态下,肛管8个方向既不存在压力的梯度变化,也不存在压力偏位方向的梯度变化。结论括约肌压力偏位的产生可能与横纹肌复合体肌束的组成和作用方向不同有关,括约肌压力偏位梯度的形成有助于肛门节制。

Objective To investigate the anatomic evidence and clinical usage of the anal sphincter pressure asymmetry in children. Methods Using PC Polygram HR (CTD-SYNECTICS Company), the anal sphincter pressures of 12 cases with fecal incontinence were compared with those of 27 normal children, including the longitudinal and radial pressure recordings of eight channels, and we obtained the longitudinal pressure gradient variations of eight channels and radial variations of pressure asymmetric direction at different circumference from the anal verge. Results In normal children, the gradients of pressure were presented in the anal canal for all of the 8 channels at the state of relaxing and contracting, and the special point was 1cm above the anal verge where there formed the maximal pressure. There also existed the variations of pressure asymmetric direction for each circumference in the anal canal, i.e. from the level of 3cm to 2cm to 1cm above the anal verge, the maximal pressure changed from the posterior position to the anterior position. And it was the anterior position of 1cm circumference from the anal verge, where formed the maximal pressure in the anal canal. However, there were no gradients of pressure and variations of pressure asymmetric direction for the patients with fecal incontinence. Based on the theories of the striated muscle complex configuration, the anatomic evidence and clinical usage of the gradient variation of the pressure asymmetry were discussed. Conclusions The structural and functional directions of the striated muscle complex possibly may contribute to the formation of the anal sphincter pressure asymmetry, and the gradient variations of the pressure asymmetry directions may be essential to the anal continence.