title: Anal Sphincter Augmentation Using Biological Material.
abstract: BACKGROUND
  The aim of this review is to provide an overview of the use of biological materials in the augmentation of the anal sphincter either as part of an overlapping sphincter repair (OSR) or anal bulking procedure.
  
  
  METHODS
  A systematic search of PubMed was conducted using the search terms "anal bulking agents," "anal sphincter repair," or "overlapping sphincter repair." Five studies using biological material as part of an overlapping sphincter repair (OSR) or as an anal bulking agent were identified.
  
  
  RESULTS
  122 patients underwent anal bulking with a biological material. Anorectal physiology was conducted in 27 patients and demonstrated deterioration in maximum resting pressure, and no significant change in maximum squeeze increment. Quality of life scores (QoLs) demonstrated improvements at 6 weeks and 6 months, but this had deteriorated at 12 months of follow up. Biological material was used in 23 patients to carry out an anal encirclement procedure. Improvements in QoLs were observed in patients undergoing OSR as well as anal encirclement using biological material. Incontinence episodes decreased to an average of one per week from 8 to 10 preoperatively.
  
  
  CONCLUSIONS
  Sphincter encirclement with biological material has demonstrated improvements in continence and QoLs in the short term compared to traditional repair alone. Long-term studies are necessary to determine if this effect is sustained. As an anal bulking agent the benefits are short-term.
authors.affiliation: Exeter Surgical Health Services Research Unit (HeSRU), Royal Devon and Exeter Hospital , Exeter , UK.
authors.forename: Nasra N
authors.initials: NN
authors.lastname: Alam
authors.affiliation: Exeter Surgical Health Services Research Unit (HeSRU), Royal Devon and Exeter Hospital , Exeter , UK.
authors.forename: Sunil K
authors.initials: SK
authors.lastname: Narang
authors.affiliation: Department of Surgery, Center for Minimally Invasive Surgery, Academic Teaching Hospital of Charité Medical School, Vivantes Hospital , Berlin , Germany.
authors.forename: Ferdinand
authors.initials: F
authors.lastname: Köckerling
authors.affiliation: Exeter Surgical Health Services Research Unit (HeSRU), Royal Devon and Exeter Hospital , Exeter , UK.
authors.forename: Ian R
authors.initials: IR
authors.lastname: Daniels
authors.affiliation: Exeter Surgical Health Services Research Unit (HeSRU), Royal Devon and Exeter Hospital , Exeter , UK.
authors.forename: Neil J
authors.initials: NJ
authors.lastname: Smart
keywords: anal bulking; anal encirclement; anal sphincter repair; biological material; fecal incontinence; overlapping sphincter repair