title: A proposed method to comprehensively define outcomes in acoustic tumor patients undergoing CyberKnife management.
abstract: BACKGROUND
  Vestibular assessment in patients with acoustic tumor (so-called vestibular schwannoma, VS) via ocular vestibular-evoked myogenic potential (oVEMP) and cervical VEMP (cVEMP) tests are not often discussed in the neurosurgical literature.
  
  
  OBJECTIVE
  This study conducted physiological and morphological assessments for VS patients before and after CyberKnife radiosurgery.
  
  
  METHODS
  Twenty patients with unilateral VS underwent a battery of tests comprising facial nerve function test, audiometry, and caloric, oVEMP and cVEMP tests before and 2 years after CyberKnife treatment at a mean dosage of 18 Gy in 3 fractions.
  
  
  RESULTS
  The abnormal percentages of caloric, oVEMP and cVEMP tests did not significantly differ before and after Cyberknife treatment, indicating that preservation of the superior and inferior vestibular nerves can be achieved after radiosurgery. Median tumor volumes, 1.49 cm3 before treatment versus 0.97 cm3 at 2 years after treatment, differed significantly.
  
  
  CONCLUSIONS
  The use of oVEMP and cVEMP tests in VS patients before stereotactic radiosurgery may help to evaluate the tumor origin from the superior or inferior vestibular nerve. It takes a short time and costs less, and it would be practical to make this a routine examination in VS patients having stereotactic radiosurgery.
authors: Department of Otolaryngology, Neurosurgical Division, National Taiwan University Hospital, Taipei, Taiwan.
authors: Mei-Chun
authors: MC
authors: Lin
authors: Chang-Mu
authors: CM
authors: Chen
authors: Ham-Min
authors: HM
authors: Tseng
authors: Furen
authors: F
authors: Xiao
authors: Yi-Ho
authors: YH
authors: Young
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001299:Audiometry; D002150:Caloric Tests; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009464:Neuroma, Acoustic / Q000503:physiopathology / Q000601:surgery*; D017063:Outcome Assessment, Health Care; D016634:Radiosurgery / Q000295:instrumentation*; D016896:Treatment Outcome; D058585:Vestibular Evoked Myogenic Potentials / Q000502:physiology*; D014725:Vestibular Nerve / Q000503:physiopathology*