title: How much of the internal sphincter may be divided during lateral sphincterotomy for chronic anal fissure in women? Morphologic and functional evaluation after sphincterotomy.
abstract: BACKGROUND
  Sphincterotomy is used to treat chronic anal fissure, but the length of the sphincterotomy is associated with incontinence.
  
  
  OBJECTIVE
  We used 3-dimensional anal ultrasonography to determine the proportion of the internal anal sphincter that may be divided during lateral internal sphincterotomy in women without predisposing them to a high risk of fecal incontinence.
  
  
  METHODS
  This was a prospective, observational cohort study conducted at a tertiary-care hospital.
  
  
  METHODS
  Women treated for chronic anal fissure with high anal resting pressure and no symptoms of fecal incontinence were selected. Asymptomatic women recruited from different departments of the same hospital served as controls to provide reference values for anal canal measurements.
  
  
  METHODS
  Patients underwent a standardized technique of lateral internal sphincterotomy.
  
  
  METHODS
  Three-dimensional ultrasonography was used to measure sphincter lengths. Continence was assessed with the Cleveland Clinic Florida (Wexner) score. The relationship between the extent of the surgically divided portion of the internal anal sphincter and the continence score was evaluated.
  
  
  RESULTS
  Successful healing was achieved in all patients within 2 months. Follow-up continence scores were significantly correlated with the extent of sphincter division. The proportion of patients with a continence score of 0 was significantly greater in patients in whom sphincter division was less than 25% in comparison with patients with a division of 25% or more. Anal canal and sphincter lengths in patients after sphincterotomy did not significantly differ from those in asymptomatic women.
  
  
  CONCLUSIONS
  The study is limited by its nonrandomized nature and the lack of preoperative ultrasound assessment.
  
  
  CONCLUSIONS
  Based on data from this study, the safe extent of division is less than 25% of the total sphincter length, which in women corresponds to less than 1 cm.
authors.affiliation: Department of Surgery, School of Medicine of the Federal University of Ceará, Fortaleza, Ceará, Brazil. smregadas@hospitalsaocarlos.com.br
authors.forename: Sthela Maria
authors.initials: SM
authors.lastname: Murad-Regadas
authors.forename: Graziela Olivia da Silva
authors.initials: GO
authors.lastname: Fernandes
authors.forename: Francisco Sergio Pinheiro
authors.initials: FS
authors.lastname: Regadas
authors.forename: Lusmar Veras
authors.initials: LV
authors.lastname: Rodrigues
authors.forename: Jacyara de Jesus Rosa
authors.initials: Jde J
authors.lastname: Pereira
authors.forename: Francisco Sergio Pinheiro
authors.initials: FS
authors.lastname: Regadas Filho
authors.forename: Iris Daiana
authors.initials: ID
authors.lastname: Dealcanfreitas
authors.forename: Erico de Carvalho
authors.initials: Ede C
authors.lastname: Holanda
mesh_terms: D000328:Adult; D000368:Aged; D001003:Anal Canal / Q000000981:diagnostic imaging / Q000601:surgery*; D002908:Chronic Disease; D015331:Cohort Studies; D005242:Fecal Incontinence / Q000453:epidemiology* / Q000517:prevention & control; D005260:Female; D005401:Fissure in Ano / Q000601:surgery*; D006801:Humans; D008365:Manometry; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology*; D011446:Prospective Studies; D016896:Treatment Outcome; D014463:Ultrasonography; D055815:Young Adult