The following is a summary of “Impact of Internal Anal Sphincter Division on Continence Disturbance in Female Patients,” published in the December 2023 issue of Gastroenterology by Murad-Regadas, et al.
A small number of studies used 3-dimensional endoanal ultrasound and anal manometry to look at the anal canal before and after surgery and found a link between sphincter division and the type, intensity, and function of fecal incontinence. For a study, researchers sought to find out how often fecal incontinence happened in people who had surgery to split the internal anal sphincter for an anal fissure or an intersphincteric anal fistula and to see if there was a link between the seriousness of symptoms and the percentage of muscle that was divided, physical measures, and anal pressures.
The Cleveland Clinic Florida Fecal Incontinence score was used to rate the intensity of the patients’ complaints, along with manometry and ultrasound. The anterior external anal sphincter, the posterior external anal sphincter, the puborectalis, and the gap lengths were all measured with ultrasound. The length, percentage, and angle of the split internal anal sphincter were also measured. About 50 women, with a mean age of 44 years, were split into two groups. 30 of them (48%) had a fistulotomy for an intersphincteric anal fistula, and 33 (52%) had a sphincterotomy for a chronic anal fissure with high anal resting pressure. 46% of people who had an internal anal sphincter division had some kind of fecal incontinence. The number of cases of fecal incontinence, the seriousness of the symptoms, and the angle of the split internal anal sphincter were all about the same in both groups. In the intersphincteric anal fistula, the length and percentage of the split internal anal sphincter were both much higher.
The lengths of the external anal sphincter and the external anal sphincter plus puborectalis were the same in both groups. When there were chronic anal cracks and high anal standing pressure, the gap length was a lot longer. It was found that half of the people who had internal anal sphincter split had bowel leakage. Even though patients who had fistulotomy had a longer and more complete division of the internal anal sphincter, the rate and severity of fecal leakage were the same in both groups. The three-dimensional endoanal ultrasound showed that the gap length was longer in the sphincterotomy group. This may be functionally important after the shorter internal anal sphincter is split, but it had the same effect on fecal leakage in both groups.
