新型人工肛门括约肌系统的初步实验研究

目的观察自行研制的可用于治疗肛门失禁的新型植入式人工肛门括约肌系统（AASS）控制肠腔内容物的效果。方法 AASS由体内执行、体外控制和经皮能量传输3个模块构成,体内外通过无线模式通信。选择屠宰市场购买新鲜宰杀的猪结肠40 cm共4段,将其垂直固定放置,上端开放注入糊状内容物,下端套入AASS并关闭,向肠内缓慢注入糊状物,观察不渗漏所需注入AASS的液体量及囊内压力值;实验动物为贵州小型猪1只,体质量26.2 kg。肠道准备后麻醉开腹,距肛门8 cm处横断直肠套入AASS吻合,经皮能量接收线圈植入皮下,损坏动物肛门括约肌。术后1周开始AASS工作实验,1个月后麻醉开腹,观察AASS植入状态及工作状况。结果离体实验和活体实验均提示,在较少的注水量（9.0～10.5 mL）的情况下,AASS可产生对肠壁作用均匀的压力分布（3.34～7.26 kPa）,满意控制肠内容物渗漏。离体状态下4只AASS夹闭肠管所产生压力与空夹时有很好的相似性,植入活体猪体内1个月取出时系统功能完好,仍可满意夹闭肠管控制流质肠内容物,连续夹闭0.5 h无明显缺血改变。结论 AASS可以很好地模拟正常人体肛门括约肌功能,有望成为治疗肛门失禁和直肠癌术后原位肛门控便的一种新方法。

Preliminary evaluation of the novel artificial anal sphincter system

Objective To explore the regulatory effect of a self-developed novel implantable artificial anal sphincter system（AASS） in the treatment of fecal incontinence.Methods The entire system was composed of 3 modules included in vivo performance,in vitro management and transcutaneous energy transmission,connected by wireless communication.Four segments of 40 cm intestine isolated from pig were mounted vertically,with its upper end opened for paste filling and its lower end closed and sleeved with AASS.The filling liquid was slowly injected into the AASS and the intracapsular pressure were observed before leakage occurred.One miniature pig with body weight of 26.2 kg was given anesthesia and laparotomy after bowel preparation.The rectum at 8 cm from the anal margin was entirely transected and fitted with AASS.In the meantime,the coils of transcutaneous energy transfer were implanted subcutaneously and anal sphincter was structurally damaged.One week after the surgery,the experiment of AASS was initiated and the operation of anesthesia and laparotomy were performed one month later to observe the status and working conditions of AASS after implantation.Results Both in vivo and in vitro experiments showed that under the condition of lower amount injection（9.0-10.5 mL）,the novel artificial anal sphincter provided uniform pressure（3.34-7.26 kPa） on intestinal wall and effectively prevented leakage of intestinal contents.The pressure from 4 clipped intestines sleeved with the AASS in vitro was similar with that from the non-clipped cases.The AASS implanted in the pig taken out 1 month following implantation functioned well with good performance to clip intestine and prevent leakage of intestinal contents,meanwhile,no significant ischemic changes were found in the intestines after being consecutively clipped for half an hour.Conclusion It is demonstrated that AASS could simulate the normal physiology of human anal sphincter very well,which might become a new treatment in bowel management for fecal incontinence and rectal cancers after anus-retained operation.