title: Utility of cVEMPs in bilateral superior canal dehiscence syndrome.
abstract: OBJECTIVE
  To determine the utility of cervical vestibular evoked myogenic potential (cVEMP) thresholds in the surgical management of bilateral superior canal dehiscence syndrome (SCDS).
  
  
  METHODS
  Retrospective review.
  
  
  METHODS
  We identified patients who underwent surgical treatment for SCDS from our database of 147 patients diagnosed with superior canal dehiscence (SCD) between 2000 and 2011 at our institution. The diagnosis of SCDS was based on clinical signs and symptoms, audiometric and cVEMP testing, and high-resolution computed tomography.
  
  
  RESULTS
  We identified 38 patients who underwent SCD surgery in 40 ears (2 bilateral). In seven patients with bilateral SCD, the more symptomatic ear had lower cVEMP thresholds, a larger air bone gap and a lateralizing tuning fork. In 13 patients with perioperative cVEMP testing, thresholds increased in 12 patients following primary repair, and no threshold shift was seen in one patient with persistence of symptoms after revision surgery. Audiometric data showed a significant mean decrease of the low-frequency air-bone gap and a mild (high-frequency) bone conduction loss after surgical repair.
  
  
  CONCLUSIONS
  We found that, 1) preoperative cVEMP thresholds, the magnitude of the air-bone gap and tuning-fork testing are important to confirm the worse ear in patients with bilateral SCD, 2) elevation of cVEMP thresholds following surgery correlates with improvement of symptoms and underscores the importance of postoperative testing in patients with bilateral disease or recurrence of symptoms and, 3) SCD plugging is associated with a partial closure of the air-bone gap and a mild (high-frequency) sensorineural hearing loss.
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, University Medical Center, Utrecht, The Netherlands.
authors.forename: Marlien E F
authors.initials: ME
authors.lastname: Niesten
authors.forename: Michael J
authors.initials: MJ
authors.lastname: McKenna
authors.forename: Barbara S
authors.initials: BS
authors.lastname: Herrmann
authors.forename: Wilko
authors.initials: W
authors.lastname: Grolman
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D001299:Audiometry; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012665:Semicircular Canals / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery*; D013577:Syndrome; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D058585:Vestibular Evoked Myogenic Potentials