Therapy of anal fissure using botulin toxin

Abstract
With chronic anal fissure, sphincterotomy to relieve sphincter spasm is the recommended therapy. This breaks the vicious circle of inflammation-pain-spasm. This obvious success is weighed against the possible risk of the operation and the risk of subsequent fecal incontinence. The following report describes a therapy for anal fissure involving injection of the external anal sphincter with botulin toxin. We have used this new method in 12 cases (7 females and 5 males; mean age, 37 years). We injected 0.1 ml of diluted toxin on both sides lateral to the fissure. The fissure healed thanks to a time-limited paresis of the sphincter in ten cases. In one case there was a recurrence within the first six months. Two patients could not be healed and had to undergo surgery. Injection of botulin toxin gives us a possible new mode of therapy in the treatment of chronic, uncomplicated anal fissures with increased sphincter tone. It is well tolerated, can be performed as an outpatient, does not cause any lesion of the continence organ, and subsequently does not lead to any permanent latent or apparent fecal incontinence.