title: Hearing preservation surgery for cochlear implantation: a meta-analysis.
abstract: OBJECTIVE
  To examine the results of hearing preservation in cochlear implantation surgery to identify surgical technical factors, electrode array design factors, and steroid usage, which predicts greater low-frequency hearing preservation.
  
  
  METHODS
  A thorough search of Medline and Pubmed of English studies from January 1, 1995, to January 1, 2013, was performed using the key words "electric and acoustic hearing" or "hybrid cochlear implant" or "EAS cochlear implant" or "partial deafness cochlear implant" or "bimodal hearing cochlear implant" or "hearing preservation cochlear implant."
  
  
  METHODS
  The meta-analysis was conducted according to the PRISMA statement. Only articles in English were included. Studies were included if hearing preservation was the primary end point. A final number of 24 studies met the inclusion criteria.
  
  
  METHODS
  Patient populations were analyzed as intention to treat. Data were extracted from raw audiograms where possible. Data were excluded if not all explanatory variables were present or if variable values were ambiguous.
  
  
  RESULTS
  The weighted least-squares regression method was used to determine the predictive power of each explanatory variable across all studies.
  
  
  CONCLUSIONS
  In this meta-analysis, the following are associated with better hearing preservation: cochleostomy over the round window approach, posterior tympanotomy over the suprameatal approach, a slow electrode array insertion technique over insertion of less than 30 seconds, a soft tissue cochleostomy seal over a fibrin glue only seal and the use of postoperative systemic steroids. Longer electrode arrays, topical steroid use, and lubricant use for electrode array insertion did not give an advantage.
authors.affiliation: *Department of Otolaryngology, Head and Neck Surgery, Stanford University Hospital and Clinics, Stanford, California; and †Section of Otolaryngology-Head and Neck Surgery, University of Chicago Medical Center, Chicago, Illinois, U.S.A.; ‡Ear Sciences Centre, School of Surgery, The University of Western Australia, Perth, Western Australia, Australia; §Department of Statistics, Stanford University, Stanford, California, U.S.A.; and ∥Ear Science Institute Australia, Perth, Western Australia, Australia.
authors.forename: Peter Luke
authors.initials: PL
authors.lastname: Santa Maria
authors.forename: Michael Brian
authors.initials: MB
authors.lastname: Gluth
authors.forename: Yongqing
authors.initials: Y
authors.lastname: Yuan
authors.forename: Marcus David
authors.initials: MD
authors.lastname: Atlas
authors.forename: Nikolas H
authors.initials: NH
authors.lastname: Blevins
mesh_terms: D019929:Cochlear Implantation / Q000379:methods*; D003054:Cochlear Implants; D006309:Hearing / Q000502:physiology*; D034381:Hearing Loss / Q000503:physiopathology / Q000601:surgery*; D006320:Hearing Tests; D006801:Humans; D011184:Postoperative Period