Treatment of chronic anal fissure botulinum toxin type A 40 U in comparison with lateral subcutaneous sphincterotomy (NCT03855046)

Abstract

AIM: to improve the results of chronic anal fissure treatment.PATIENTS AND METHODS: the prospective randomized study included 176 patients divided in two groups. Eighty-eight patients underwent fissure excision in combination with injection of botulinum toxin type A (incobotulinum toxin) into the internal anal sphincter (main group, BTA), and 88 patients underwent anal fissure excision in combination with lateral subcutaneous sphincterotomy (control group, LIS).RESULTS: on the 30th day after surgery, spasm of internal anal sphincter, according to profilometry, persisted in 14.8% of patients of the main group (BTA) and 22.7% of patients in the control group (LSS) (p = 0.18), and on the 60th day in 20.4% and 14.8% of patients, respectively (p = 0.32). On the 60th day after surgery, the postoperative wound did not epithelialize in 14% of patients in the BTA group and 1% of the LSS group (p = 0.0006). On the 30th day after surgery, complaints of incontinence were noted by 32% of patients in the BTA group and 31% in the LSS group (p = 0.87), on the 60th day — 7% and 11% of patients, respectively (p = 0.29). The intensity of pain after surgery in the compared groups did not differ both after defecation and during the day (p > 0.05). Expansion of the surgery volume increases the chance of developing temporary anal sphincter incontinence (ASI) by 2.44 times on the 30th day of observation (p = 0.01) and by 3 times — on day 60 (p = 0.04). The use of BTA as a method of internal anal sphincter relaxation increases the chance of slowing down the epithelization of the postoperative wound by 13.7 times [p = 0.01], and the expansion of the surgery volume — by 3.47 times [p = 0.03].CONCLUSION: the use 40 U of botulinum toxin type A after anal fissure excision is not inferior to lateral subcutaneous sphincterotomy in elimination of spasm internal anal sphincter with a comparable incidence of temporary anal sphincter incontinence within 2 months after surgery. Neurotoxin serves as an alternative to sphincterotomy, however, in some cases, it requires the addition of a agent containing human recombinant epidermal growth factor to the postoperative management of patients.