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.