Systematic review and meta-analysis of randomized controlled trials comparing botulinum toxin injection with lateral internal sphincterotomy for chronic anal fissure

The aim of this review is to systematically analyze the prospective randomized controlled trials on the efficacy of botulinum toxin injection (Botox) vs. lateral internal sphincterotomy (LIS) for the treatment of chronic anal fissure (CAF). A systematic review of the literature was undertaken. The prospective randomized controlled trials on the effectiveness of Botox vs. LIS for the management of CAF were selected according to specific criteria and analyzed to generate pooling data. Four studies encompassing 279 patients were qualified for the meta-analysis. There was a statistically significant higher healing in LIS group compared with Botox group (RR 1.31[1.57, 1.50] 95% CI, z = 4.11, p < 0.0001). Absolute benefit increase rate (ABI) is 23% for LIS group compared with Botox group. The recurrence rate was statistically significantly higher in Botox groups than in LIS groups (RR 5.83[2.96, 11.49] 95% CI, z = 5.09, p < 0.00001).LIS was associated with a high rate of minor anal incontinence as compared to Botox (RR 0.08[0.01, 0.59] 95% CI, z = 2.47, p = 0.01). Botulinum toxin injection was associated with a higher rate of recurrent disease. LIS was more effective in healing chronic anal fissure.