title: Endoscopic skull base reconstruction of large dural defects: a systematic review of published evidence.
abstract: OBJECTIVE
  Systematically review the outcomes of endoscopic endonasal techniques to reconstruct large skull base defects (ESBR). Such surgical innovation is likely to be reported in case series, retrospective cohorts, or case-control studies rather than higher level evidence.
  
  
  METHODS
  Systematic review and meta-analysis.
  
  
  METHODS
  Embase (1980-December 7, 2010) and MEDLINE (1950-November 14, 2010) were searched using a search strategy designed to include any publication on endoscopic endonasal reconstruction of the skull base. A title search selected those articles relevant to the clinical or basic science of an endoscopic approach. A subsequent abstract search selected articles of any defect other than simple cerebrospinal fluid (CSF) fistula, sella only, meningoceles, or simple case reports. The articles selected were subject to full-text review to extract data on perioperative outcomes for ESBR. Surgical technique was used for subgroup analysis.
  
  
  RESULTS
  There were 4,770 articles selected initially, and full-text analysis produced 38 studies with extractable data regarding ESBR. Of these articles, 12 described a vascularized reconstruction, 17 described free graft, and nine were mixed reconstructions. Three had mixed data in clearly defined patient groups that could be used for meta-analysis. The overall CSF leak rate was 11.5% (70/609). This was represented as a 15.6% leak rate (51/326) for free grafts and a 6.7% leak rate (19/283) for the vascularized reconstructions (χ(2)  = 11.88, P = .001).
  
  
  CONCLUSIONS
  Current evidence suggests that ESBR with vascularized tissue is associated with a lower rate of CSF leaks compared to free tissue graft and is similar to reported closure rates in open surgical repair.
authors.affiliation: Department of Otolaryngology and Skull Base Surgery, St. Vincent's Hospital, Sydney, New South Wales, Australia. richard@richardharvey.com.au.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Harvey
authors.forename: Priscilla
authors.initials: P
authors.lastname: Parmar
authors.forename: Raymond
authors.initials: R
authors.lastname: Sacks
authors.forename: Adam M
authors.initials: AM
authors.lastname: Zanation
mesh_terms: D002559:Cerebrospinal Fluid Rhinorrhea / Q000209:etiology / Q000601:surgery*; D004388:Dura Mater / Q000601:surgery*; D004724:Endoscopy / Q000379:methods*; D006801:Humans; D009296:Nasal Cavity; D019651:Plastic Surgery Procedures / Q000379:methods*; D019291:Skull Base / Q000601:surgery*; D013524:Surgical Flaps