title: Cost-effective analysis of unilateral vestibular weakness investigation.
abstract: OBJECTIVE
  To evaluate the cost-effectiveness of obtaining a magnetic resonance imaging (MRI) in patients with abnormal electronystagmography (ENG) or videonystagmography (VNG) results.
  
  
  METHODS
  Retrospective chart review.
  
  
  METHODS
  Academic specialty center.
  
  
  METHODS
  Patients presenting with vertigo between January 1, 2010, and August 30, 2013.
  
  
  METHODS
  Patients who fit the following abnormal criteria were included in the study: unilateral caloric weakness (≥20%), abnormal ocular motor testing, and nystagmus on positional testing. Patients with abnormal findings who then underwent MRI with gadolinium were evaluated.
  
  
  RESULTS
  Of the 1,996 charts reviewed, there were 1,358 patients who met the inclusion criteria. The average age of these patients was 62 years (12-94 yr). The male:female ratio was approximately 1:2. Of the 1,358 patients, 253 received an MRI with the following pathologies: four vestibular schwannomas, three subcortical/periventricular white matter changes suspicious for demyelinating disease, four acute cerebellar/posterior circulation infarct, two vertebral artery narrowing, one pseudomeningocele of internal auditory canal, and two white matter changes indicative of migraines. The positive detection rate on MRI was 5.5% based on MRI findings of treatable pathologies causing vertigo. Average cost of an MRI is $1,200, thereby making the average cost of identifying a patient with a positive MRI finding $15,180.
  
  
  CONCLUSIONS
  In our study, those patients with a positive MRI had a constellation of symptoms and findings (asymmetric sensorineural hearing loss, tinnitus, vertigo, and abnormal ENG/VNG). Cost-effectiveness can be improved by ordering an MRI only when clinical examination and VNG point toward a central pathology. Clinical examination and appropriate testing should be factored when considering the cost-effectiveness of obtaining an MRI in patients with abnormal ENG/VNG findings.
authors.affiliation: *Department of Otolaryngology-Head and Neck Surgery, New York Eye and Ear Infirmary, New York; and †New York Medical College, Valhalla, New York, U.S.A.
authors.forename: Michele M
authors.initials: MM
authors.lastname: Gandolfi
authors.forename: Erin K
authors.initials: EK
authors.lastname: Reilly
authors.forename: Jessica
authors.initials: J
authors.lastname: Galatioto
authors.forename: Randy B
authors.initials: RB
authors.lastname: Judson
authors.forename: Ana H
authors.initials: AH
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D003362:Cost-Benefit Analysis; D004584:Electronystagmography / Q000191:economics*; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis* / Q000191:economics; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000191:economics*; D008297:Male; D008875:Middle Aged; D009464:Neuroma, Acoustic / Q000175:diagnosis* / Q000191:economics; D012189:Retrospective Studies; D014012:Tinnitus / Q000175:diagnosis* / Q000191:economics; D014717:Vertigo / Q000175:diagnosis* / Q000191:economics / Q000209:etiology; D055815:Young Adult