title: Botulinum toxin injection versus lateral internal sphincterotomy for the treatment of chronic anal fissure: randomized prospective controlled trial.
abstract: OBJECTIVE
  Lateral internal sphincterotomy has been the gold standard treatment for chronic anal fissure, but it still carries the risk of permanent damage of the anal sphincter, which has led to the implementation of alternative treatment like botulinum toxin injection. The aim of this randomized prospective controlled trial was to compare the efficacy and morbidity of botulinum toxin injection and lateral internal sphincterotomy in the treatment of chronic anal fissure.
  
  
  METHODS
  Fifty consecutive adults with chronic anal fissure were randomly treated with either lateral internal sphincterotomy or botulinum toxin (BT) injection with 50 U BT into the internal sphincter. The complications, healing and recurrence rate, and incontinence score were assessed 2, 3, 6, 12 months after the procedure.
  
  
  RESULTS
  Inspection at the 2-month visit revealed complete healing of the fissure in 11 (44 %) of the patients in the BT group and 22 (88 %) of the patients in the lateral internal sphincterotomy (LIS) group (p = 0.001). At the 3-month visit, there was no significant difference between the two groups in healing. The overall recurrence rate after 6 months in the BT group was higher than in the LIS group (p < 0.05). In the 3-month follow-up, the LIS group had a higher rate of anal incontinence compared to the BT group (p < 0.05). The final percentage of incontinence was 4 % in the LIS group (p > 0.05).
  
  
  CONCLUSIONS
  The treatment of chronic anal fissure must be individualized depending on the different clinical profiles of patients. Botulinum toxin injection has a higher recurrence rate than LIS, and LIS provides rapid and permanent recovery. However, LIS carries a higher risk of anal incontinence in patients.
authors.affiliation: Department of General Surgery, Ayatollah Taleghani Hospital, Shahid Beheshti University of Medical Sciences, PO Box 1545633319, Tehran, Iran.
authors.forename: Neda
authors.initials: N
authors.lastname: Valizadeh
authors.forename: Niloufar Yahyapour
authors.initials: NY
authors.lastname: Jalaly
authors.forename: Mohsen
authors.initials: M
authors.lastname: Hassanzadeh
authors.forename: Fereshteh
authors.initials: F
authors.lastname: Kamani
authors.forename: Zohreh
authors.initials: Z
authors.lastname: Dadvar
authors.forename: Shapour
authors.initials: S
authors.lastname: Azizi
authors.forename: Babak
authors.initials: B
authors.lastname: Salehimarzijarani
mesh_terms: D000328:Adult; D001003:Anal Canal / Q000601:surgery*; D019274:Botulinum Toxins, Type A / Q000008:administration & dosage / Q000627:therapeutic use*; D016009:Chi-Square Distribution; D002908:Chronic Disease; D005260:Female; D005401:Fissure in Ano / Q000188:drug therapy* / Q000601:surgery*; D006801:Humans; D015552:Injections, Intralesional; D008297:Male; D009465:Neuromuscular Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D011183:Postoperative Complications; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A