Botulinum toxin for the treatment of anal fissure

Background: The classic treatment for uncomplicated anal fissure is surgica l sphincterotomy, i.e. cutting of the internal anal sphincter, thus elimina ting spasm of this muscle and breaking the vicious circle of pain, spasm an d inflammation. Recently, however, botulinum toxin has become available for the treatment of muscular dystonias, and thus for anal fissure. In the pre sent study, we investigated the effectiveness of treatment with botulinum t oxin in 76 patients with uncomplicated anal fissure. Material and Method Th e 76 patients received an injection of 40 U of botulinum toxin on each side of the fissure. Response was monitored 7, 30 and 90 days later. All patien ts who did not show clear improvement after 30 days received a second dose of 40 U on each side. Results: After 90 days, 51 patients (67%) showed comp lete recovery, 19 patients (25%) substantial improvement though not complet e recovery, and 6 patients (8%) no significant improvement. Transitory gas incontinence was reported by 2 patients (2.6%), and 1 patient presented hem orrhoidal thrombosis. Discussion: Botulinum toxin enables chemical denervat ion of the internal sphincter, facilitating healing of the anal fissure. It s principal advantages with respect to surgical sphincterotomy are the abse nce of the general risks of surgery, and reduced incidence of incontinence, which even if it occurs tends to be transitory. The technique does not req uire hospitalization and is well tolerated. It appears suitable for the ini tial treatment of uncomplicated anal fissure, reserving surgical treatment for those cases which fail to response adequately. Copyright (C) 1999 S. Ka rger AG, Basel.