The treatment of chronic anal fissure with botulinum toxin.
BACKGROUND/AIMS: The aim of this study was to evaluate the effectiveness of botulinum toxin for the treatment of uncomplicated dorsal chronic idiopathic anal fissure. MATERIAL AND METHODS: Forty-five patients who reported post defecatory anal pain since two months or more were given a total of 20U botulinum toxin in the anal sphincter apparatus on both sides as well as below the anal fissure. RESULTS: Thirty-seven patients received a second session of 25U botulinum toxin injection. Thirty-five patients (78%) presented completely healed anal fissure, while ten needed lateral internal sphincterotomy. All patients were followed up for 8-36 months. Two patients relapsed. CONCLUSION: Local injection of botulinum toxin is a new and safe treatment; however, two sessions of injections are necessary to be effective and long-term follow-up to assess the recurrence rate of fissure is needed to evaluate further this method of treatment. Partial internal lateral sphincterotomy is no more the treatment of choice for chronic anal fissure.