title: Vestibular evoked myogenic potentials to sound and vibration: characteristics in vestibular migraine that enable separation from Meniere's disease.
abstract: OBJECTIVE
  It can be difficult to distinguish vestibular migraine (VM) from Menière's disease (MD) in its early stages. Using vestibular-evoked myogenic potentials (VEMPs), we sought to identify test parameters that would help discriminate between these two vestibular disorders.
  
  
  METHODS
  We first recorded ocular and cervical VEMPs (oVEMP/cVEMP) to air-conducted clicks and bone-conducted vibration in 30 control participants, 30 participants with clinically definite VM and 30 participants with clinically probable VM. Results were compared with a group of 60 MD patients from a previous study. oVEMPs and cVEMPs were then recorded at octave frequencies of 250 Hz to 2000 Hz in 20 controls and 20 participants each with clinically definite VM and MD. Inter-aural amplitude asymmetry ratios and amplitude frequency ratios were compared between groups.
  
  
  RESULTS
  For click, tendon-hammer-tap and minishaker-tap VEMPs, there were no significant differences in reflex amplitudes or symmetry between controls, definite VM and probable VM. Compared with MD patients, participants with VM had significantly fewer reflex abnormalities for click-cVEMP, click-oVEMPs and minitap-cVEMPs. The ratio of cVEMP amplitude generated by tone bursts at a frequency of 0.5 kHz to that generated by 1 kHz was significantly lower for MD affected ears than for VM or controls ears. cVEMP asymmetry ratios for 0.5 kHz tone bursts were significantly higher for MD than VM.
  
  
  CONCLUSIONS
  The 0.5/1 kHz frequency ratio, 0.5 kHz asymmetry ratio and caloric test combined, separated MD from VM with a sensitivity of 90.0% and specificity of 70.0%.
authors.affiliation: University of Sydney, Australia.
authors.forename: Rachael L
authors.initials: RL
authors.lastname: Taylor
authors.forename: Alessandro S
authors.initials: AS
authors.lastname: Zagami
authors.forename: William Pr
authors.initials: WP
authors.lastname: Gibson
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Black
authors.forename: Shaun Rd
authors.initials: SR
authors.lastname: Watson
authors.forename: Michael G
authors.initials: MG
authors.lastname: Halmagyi
authors.forename: Miriam S
authors.initials: MS
authors.lastname: Welgampola
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008575:Meniere Disease / Q000150:complications / Q000175:diagnosis*; D008881:Migraine Disorders / Q000150:complications / Q000175:diagnosis*; D013016:Sound; D014717:Vertigo / Q000175:diagnosis / Q000209:etiology; D058585:Vestibular Evoked Myogenic Potentials / Q000502:physiology*; D014732:Vibration