Botulinum toxin injection versus internal anal sphincterotomy for the treatment of chronic anal fissure

BACKGROUND: Anal fissure is a chronic condition characterized by painful defecation and rectal bleeding. The aim of this study was to compare injection of botulinum toxin versus surgical sphincterotomy for treatment of chronic anal fissure. PATIENTS AND METHODS: In a quasi-experimental trial in a university hospital in Kerman, 50 patients diagnosed with chronic anal fissure received 20 units botulinum toxin (n = 25) or underwent lateral internal sphincterotomy (n = 25). All patients were evaluated for pain, bleeding and healing of the fissure from one to six months later by another surgeon. The data was analyzed by SPSS software with the Mann-Whitney and Fisher's exact tests. RESULTS: One month after treatment, the rate of healing and bleeding in the operation group was better than in the toxin group (P < 0.05), while pain was equal. After two months, none of the patients in either group had complications. After six months follow-up, bleeding, pain and healing were better in the operation group. CONCLUSION: In the clinical evaluation, botulinum toxin is an effective alternative nonsurgical modality for the treatment of chronic anal fissure. We recommend botulinum toxin as the first step in treatment because of the 60% chance of cure with an easily performed treatment.