Prospective, Randomized, Controlled Trial of Ultra-modified Internal Sphincterotomy vs Closed Lateral Internal Sphincterotomy for Chronic Fissure-in-Ano

Abstract

Background Currently, the lateral internal sphincterotomy is the treatment of choice for a chronic anal fissure (CAF). However, the length of the internal sphincter incision varies, due to lack of standardization. Insufficient length increases the risk of recurrence. To compare a new ultra-modified internal sphincterotomy (UMIS) to the closed lateral internal sphincterotomy (CLIS) for treating CAF, based on internal anal sphincter function and postoperative complications. The primary endpoint was continence after UMIS. The secondary outcomes were CAF healing complications, visual analog scale pain scores, and sphincter pressures. Methods This was a prospective, randomized, controlled trial (block randomization method). 200 patients with CAFs were randomly assigned to receive either UMIS (n = 100) or the closed lateral internal sphincterotomy (CLIS) (n = 100). Follow-up was 2 years. RESULTS: All (100%) patients in both groups showed clinical improvement at 1 month post-surgery. Recurrences were accompanied by deteriorations in Cleveland Clinic Florida Fecal Incontinence scores at 12 months and 2 years (P < .05). The groups showed significant differences in fissure healing rates and pain scores. After 1 and 2 years, incontinence rates were significantly higher, and patient satisfaction scores were significantly lower in the CLIS group than the UMIS group (P < .05). Conclusion UMIS provided a faster healing rate and fewer side effects than the CLIS for treating CAFs. These results might lead to a standardized treatment among surgeons.