Efficacy and Safety of Endoanal Ultrasound–Guided Botulinum Toxin in Chronic Anal Fissure

We aimed to evaluate the efficacy and safety of endoanal ultrasound (EAUS)–guided botulinum toxin (BT) in the treatment of chronic anal fissure (CAF). All patients were classified into 2 groups: conventional and EAUS groups. In total, 90 units of BT were injected into the internal anal sphincter at the 3, 6, and 9 o’clock positions in the EAUS group. An injection was performed into the intersphincteric space at the 3, 6, and 9 o’clock positions in the conventional group. Adverse effects and efficacy were analyzed. There were 44 patients: 26 in the conventional group and 18 in the EAUS group. Pain and incontinence rates were similar between groups ( P > .05). The efficacy rate was higher in the EAUS group (69.23%) than in the conventional group (81.82%), but this difference was not significant ( P = .466). EAUS–guided BT injection is safe and effective in patients with CAFs.