title: Botulinum toxin A injection in ISDN ointment-resistant chronic anal fissures.
abstract: BACKGROUND
  In the treatment of chronic anal fissures (CAFs), surgical sphincterotomy is more commonly being replaced by chemical sphincterotomy. After the good results of our pilot study including 32 patients, we now describe the effect of botulinum toxin A (BT-A) in a consecutive series of 100 patients with isosorbide dinitrate (ISDN) ointment-resistant CAFs.
  
  
  METHODS
  From October 2002 until August 2005, 100 patients (52 males, 48 females) with a median age of 45 (20-79) years were treated with an injection of 40-100 IU BT-A (Dysport, Ipsen, The Netherlands) in the internal anal sphincter.
  
  
  RESULTS
  After a median follow-up of 10 (4-38) months, 77 of the 100 CAFs (77%) were cured. 20 patients were given a second injection, 1 a third and 1 a fourth injection. In 11 patients a fissure recurred (14%). In 1 patient (1%) there was temporary incontinence due to flatus.
  
  
  CONCLUSIONS
  With an early response rate of 77% and an overall success rate of 66%, BT-A injections appear to be effective in patients with ISDN ointment-resistant CAFs if initial non-responders are retreated. These results are in concordance with the results of our pilot study. It is a simple technique with little or no side effects, that does not compromise future treatments. Its place in the first-line treatment of CAFs should be investigated further.
authors.affiliation: Department of Surgery, Medisch Spectrum Twente, Enschede, The Netherlands.
authors.forename: M E
authors.initials: ME
authors.lastname: Witte
authors.forename: J M
authors.initials: JM
authors.lastname: Klaase
mesh_terms: D000328:Adult; D000368:Aged; D001003:Anal Canal / Q000187:drug effects*; D019274:Botulinum Toxins, Type A / Q000008:administration & dosage*; D004351:Drug Resistance; D005260:Female; D005401:Fissure in Ano / Q000188:drug therapy*; D005500:Follow-Up Studies; D006801:Humans; D007267:Injections / Q000379:methods; D007548:Isosorbide Dinitrate / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009498:Neurotoxins / Q000008:administration & dosage*; D020030:Nitric Oxide Donors / Q000627:therapeutic use; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D009498:Neurotoxins; D020030:Nitric Oxide Donors; D019274:Botulinum Toxins, Type A; D007548:Isosorbide Dinitrate