The status of the contralateral ear in established unilateral Menière's disease

To determine the incidence of measurable audiometric changes in the contralateral ear and clinical bilateral Menière's disease in individuals with longstanding established unilateral Menière's disease.

Analysis of data in an ongoing prospective study.

One hundred and one patients who were treated with intratympanic gentamicin installation for disabling unilateral Menière's disease were followed up for a minimum of 2 years. The mean follow-up time between the initial diagnosis to the last audiogram conducted was 12 +/- 7 (range 2-45) years, and the mean follow-up between the first and last audiograms conducted in our clinic was 5 +/- 3 (range 2-15) years. The incidence of Menière's disease (clinical diagnosis) as compared with audiometric changes in the contralateral ear was analyzed.

Compared with several published reports, the development of bilateral Menière's disease in our series within the described observation period was much lower (5%). The incidence of contralateral isolated hearing loss in the low frequencies was 16% (average threshold of .25 and .5 kHz of 25 dB or more). The time interval between the initial diagnosis and the onset of contralateral findings ranged from 0 to 26 years.

In our experience, individuals with disabling longstanding unilateral disease are not likely to develop bilateral disease. However, a small but significant percentage of patients have audiometric changes in the low frequencies of the contralateral ear (.25, .5 kHz).