COMPARISON OF THE THERAPEUTIC EFFECTS OF 25 U AND 50 U DOSES OF BOTULINUM TOXIN IN CHRONIC ANAL FISSURE

Chronic anal fissure is maintained by contraction of the internal anal sphincter. Sphincterotomy, which is successful in 85% to 95% of patients, permanently weakens the sphincter and therefore might be associated with anal deformity, infections and incontinence. The object of the present study was to compare the therapeutic effects of 25U and 50U doses of botulinum toxin in chronic anal fissure. 69 patients received intrasphincteric injection of botulinum toxin type A (Dysport). 58 patients with idiopathic, non-complicated chronic anal fissure were included in a non randomized prospective trial of intrasphincteric injection of botulinum toxin type A (Dysport). The patients were assessed only by clinical evaluation. Patients were divided into two treatment groups based on the number of botulinum toxin units injected. Patients in the first group(No=34) were treated with 25 unit. Patients in the second group(No=24) were treated with 50 unit. Two months after treatment, 26 patients in the first group and 16 patients in the second group had healing scar. Symptomatic improvement was observed in 3 patients in the first group and in 2 patients in the second group. According to statistical analysis which was done via Chi-square test no significant difference was found between two groups. Therefore, it can be concluded that botulinum toxin is safe and effective in the treatment of chronic anal fissure. It is less expensive and much easier to perform than surgical treatment. The healing rate is not related to the dose. No permanent or temporary damage to the continence mechanism was detected in these patients.