title: Meniere's disease: prevalence of contralateral ear involvement.
abstract: OBJECTIVE
  Determine the prevalence and time interval for conversion from unilateral to bilateral involvement in Meniere's disease and cochlear hydrops.
  
  
  METHODS
  Retrospective chart review in a tertiary otologic referral center.
  
  
  METHODS
  232 patients diagnosed with Meniere's Disease (n=186) or cochlear hydrops (n=46) between 1959 and 2001, who visited the clinic over a five-year period between 1997-2001 and have at least 2 audiograms more than 12 months apart.
  
  
  METHODS
  Prevalence of cochlear hydrops relative to Meniere's Disease, rate of progression from unilateral to bilateral involvement; interval between unilateral onset of symptoms and bilateral involvement; and rate of progression from cochlear hydrops to Meniere's disease.
  
  
  RESULTS
  Initial diagnosis was Meniere's disease in 71% and cochlear hydrops in 29% of all 950 hydropic patients presenting between 1997 and 2001. In the study sample, Meniere's disease was bilateral at presentation in 11%; an additional 12% (14% of unilaterals) became bilateral during the follow-up period. At presentation, 6.5% of cochlear hydrops patients were bilateral, with another 26% becoming bilateral. Conversion from cochlear hydrops to Meniere's disease occurred in 33% and some of these are included among the bilateral. The average time interval for conversion from unilateral to bilateral Meniere's was 7.6 years (SD=7.0 years).
  
  
  CONCLUSIONS
  Most otologists are aware of the potential for contralateral ear involvement and conversion from cochlear hydrops to Meniere's disease after diagnosis. These changes are significant, require long-term follow-up for detection, and may necessitate further treatment. Patients should be counseled regarding this potential when interventions are considered, especially with respect to ablative treatments.
authors.affiliation: House Clinic and House Ear Institute, Clinical Studies Department, Los Angeles, CA 90057, USA. jhouse@hei.org
authors.forename: John W
authors.initials: JW
authors.lastname: House
authors.forename: Joni K
authors.initials: JK
authors.lastname: Doherty
authors.forename: Laurel M
authors.initials: LM
authors.lastname: Fisher
authors.forename: M Jennifer
authors.initials: MJ
authors.lastname: Derebery
authors.forename: Karen I
authors.initials: KI
authors.lastname: Berliner
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018450:Disease Progression; D018159:Endolymphatic Hydrops / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology; D005260:Female; D006312:Hearing Loss, Bilateral / Q000175:diagnosis; D006801:Humans; D008297:Male; D008575:Meniere Disease / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D008875:Middle Aged; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D014717:Vertigo / Q000175:diagnosis