title: Long-term outcomes of Botulinum toxin in the treatment of chronic anal fissure: 5 years of follow-up.
abstract: BACKGROUND
  Chronic anal fissure is a frequent and disabling disease, often affecting young adults. Botulinum toxin and lateral internal sphincterotomy are the main therapeutic options for refractory cases. Botulinum toxin is minimally invasive and safer compared with surgery, which carries a difficult post-operative recovery and fecal incontinence risk. The long-term efficacy of Botulinum toxin is not well known.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the long-term efficacy and safety of Botulinum toxin in the treatment of chronic anal fissure.
  
  
  METHODS
  This was a retrospective study at a single center, including patients treated with Botulinum toxin from 2005 to 2010, followed over at least a period of 5 years. All patients were treated with injection of 25U of Botulinum toxin in the intersphincteric groove. The response was registered as complete, partial, refractory and relapse.
  
  
  RESULTS
  Botulinum toxin was administered to 126 patients, 69.8% (n= 88) were followed over a period of 5 years. After 3 months, 46.6% (n= 41) had complete response, 23.9% (n= 21) had partial response and 29.5% (n= 26) were refractory. Relapse was observed in 1.2% (n= 1) at 6 months, 11.4% (n= 10) at 1 year, 2.3% (n= 2) at 3 years; no relapse at 5 years. The overall success rate was 64.8% at 5 years of follow-up. Botulinum toxin was well tolerated by all patients and there were no complications.
  
  
  CONCLUSIONS
  The use of Botulinum toxin to treat patients with chronic anal fissure was safe and effective in long-term follow-up.
authors.affiliation: Department of Gastroenterology, Centro Hospitalar de Leiria, Leiria, Portugal.
authors.forename: Sandra
authors.initials: S
authors.lastname: Barbeiro
authors.affiliation: Department of Gastroenterology, Centro Hospitalar de Leiria, Leiria, Portugal.
authors.forename: Catarina
authors.initials: C
authors.lastname: Atalaia-Martins
authors.affiliation: Department of Gastroenterology, Centro Hospitalar de Leiria, Leiria, Portugal.
authors.forename: Pedro
authors.initials: P
authors.lastname: Marcos
authors.affiliation: Department of Gastroenterology, Centro Hospitalar de Leiria, Leiria, Portugal.
authors.forename: Cláudia
authors.initials: C
authors.lastname: Gonçalves
authors.affiliation: Department of Gastroenterology, Centro Hospitalar de Leiria, Leiria, Portugal.
authors.forename: Manuela
authors.initials: M
authors.lastname: Canhoto
authors.affiliation: Department of Gastroenterology, Centro Hospitalar de Leiria, Leiria, Portugal.
authors.forename: Bruno
authors.initials: B
authors.lastname: Arroja
authors.affiliation: Department of Gastroenterology, Centro Hospitalar de Leiria, Leiria, Portugal.
authors.forename: Filipe
authors.initials: F
authors.lastname: Silva
authors.affiliation: Department of Gastroenterology, Centro Hospitalar de Leiria, Leiria, Portugal.
authors.forename: Isabel
authors.initials: I
authors.lastname: Cotrim
authors.affiliation: Department of Gastroenterology, Centro Hospitalar de Leiria, Leiria, Portugal.
authors.forename: Liliana
authors.initials: L
authors.lastname: Eliseu
authors.affiliation: Department of Gastroenterology, Centro Hospitalar de Leiria, Leiria, Portugal.
authors.forename: Antonieta
authors.initials: A
authors.lastname: Santos
authors.affiliation: Department of Gastroenterology, Centro Hospitalar de Leiria, Leiria, Portugal.
authors.forename: Helena
authors.initials: H
authors.lastname: Vasconcelos
keywords: Botulinum toxin; Chronic anal fissure; chemical sphincterotomy; efficacy; long-term outcome; safety