title: A meta-analysis of surgical treatment for vestibular schwannoma: is hospital volume related to preservation of facial function?
abstract: OBJECTIVE
  To investigate the relation between hospital volume and preservation ratios of facial function in surgery for vestibular schwannoma.
  
  
  METHODS
  A meta-analysis was conducted on current literature concerning preservation ratios of facial function after surgical resection of vestibular schwannoma. Studies reported by the House-Brackmann grading system for facial function were searched; all studies were published in English in peer-reviewed journals between 1992 and 2007.
  
  
  METHODS
  Articles had to report 1) patients who had surgery for vestibular schwannoma, 2) House-Brackmann grades for facial function, and 3) calendar time and number of procedures.
  
  
  METHODS
  Standard methods for meta-analysis were adapted.
  
  
  RESULTS
  Data were pooled by weighing studies according to their accuracy. Results were sorted for low-, moderate-, and high-volume hospitals. Linear relations were quantified by metaregression analysis (n = 5,560).
  
  
  CONCLUSIONS
  Findings of this meta-analysis suggest that there is a linear relation between hospital volume and preservation ratio of facial function. The concentration of surgical treatment might be a consideration to optimize clinical outcome. Prospective and nationwide registration of surgical results might contribute to more definitive conclusions regarding outcome of vestibular schwannoma surgery.
authors: Department of Otorhinolaryngology, Leiden University Medical Center, Leiden, The Netherlands.
authors: Deniz
authors: D
authors: Hastan
authors: Jan P
authors: JP
authors: Vandenbroucke
authors: Andel G L
authors: AG
authors: van der Mey
mesh_terms: D005145:Face / Q000502:physiology*; D020220:Facial Nerve Injuries / Q000209:etiology; D006761:Hospitals / Q000706:statistics & numerical data*; D006801:Humans; D009464:Neuroma, Acoustic / Q000601:surgery*; D019635:Neurosurgical Procedures; D011183:Postoperative Complications; D012042:Registries; D016896:Treatment Outcome