title: A diagnostic test for Ménière's Disease and Cochlear Hydrops: impaired high-pass noise masking of auditory brainstem responses.
abstract: OBJECTIVE
  Endolymphatic hydrops in patients diagnosed with Ménière's disease causes changes in the response properties of the basilar membrane that lead to impaired high-pass noise masking of auditory brainstem responses to clicks.
  
  
  BACKGROUND
  Ménière's disease is defined as the idiopathic syndrome of endolymphatic (cochlear) hydrops, which is an abnormal increase in the volume of cochlear fluid (endolymph) in the inner ear. Accurate detection and diagnosis are important but difficult because of the lack of sufficiently sensitive tests.
  
  
  METHODS
  Two populations were compared: (1) 38 non-Ménière's normal-hearing subjects; and (2) 23 patients who, at the time of testing, continued to have at least three of the four hallmark symptoms (i.e., tinnitus, vertigo, fluctuating hearing loss, and fullness) used in the diagnosis of Ménière's disease. Auditory brainstem responses to clicks presented ipsilaterally with masking noise that was high-pass filtered at various frequencies were recorded.
  
  
  RESULTS
  In the Ménière's patients, the masking noise is insufficient such that an undermasked Wave V is still present at a latency similar to that of Wave V in the response to the clicks alone. In the control non-Ménière's normal-hearing subjects, this undermasked component was either absent or significantly delayed because of the masking noise. The difference in the delays between these populations is such that the distributions do not overlap, resulting in 100% sensitivity and 100% specificity.
  
  
  CONCLUSIONS
  This test is able to distinguish objectively active Ménière's disease in individuals and may show promise for tracking changes in the severity of the disease caused by progression or treatment.
authors: Electrophysiology Department, House Ear Institute, Los Angeles, California 90057, USA.
authors: Manuel
authors: M
authors: Don
authors: Betty
authors: B
authors: Kwong
authors: Chiemi
authors: C
authors: Tanaka
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D015834:Cochlear Diseases / Q000175:diagnosis*; D018159:Endolymphatic Hydrops / Q000175:diagnosis*; D016057:Evoked Potentials, Auditory, Brain Stem; D005260:Female; D006801:Humans; D008297:Male; D008575:Meniere Disease / Q000175:diagnosis*; D008875:Middle Aged; D009622:Noise; D010470:Perceptual Masking; D012680:Sensitivity and Specificity