Acute low-tone sensorineural hearing loss without vertigo.

OBJECTIVE

To study the pathophysiological features of acute low-tone sensorineural hearing loss without vertigo (ALHL) and its correlation with Meniere's disease.

DESIGN

Retrospective review of medical charts of patients with ALHL.

SETTING

University hospital clinic.

PARTICIPANTS

Eighty consecutive patients with ALHL, including 45 patients whose conditions were followed up for more than 3 years (average, 5 years 2 months; range, 3 years 3 months to 8 years).

OUTCOME MEASURES: Age and sex distributions and results of audiological and neuro-otological tests, initial outcome, recurrence rates, and differences between patients with and without recurrence.

RESULTS

About 75% (62/80) of the patients were between the ages of 30 and 60 years and the female-male ratio was 2:6. Positive glycerol test results were found in 74% (26/35) of patients and abnormally increased negative summating potential/action potential ratio in 63% (50/80). No abnormalities were found on neuro-otological tests. Hearing loss improved within 3 months in 84% (67/80) of the patients. Of 45 patients followed up for more than 3 years, 28 (62%) showed no evidence of recurrence, 12 (27%) developed cochlear Meniere's disease, and five (11%) developed classic Meniere's disease. No significant differences were found at the first examination between patients with and without recurrence.

CONCLUSIONS

These results suggest that ALHL may be caused by endolymphatic hydrops confined to the cochlea and that ALHL does not always lead to cochlear or classic Meniere's disease.