[Transtympanic electrocochleography in Menière's disease].

In order to examine the usefulness of the electrocochleography (ECoG) in the diagnosis of Menière's disease and establish the diagnostic criteria in Chinese, transtympanic ECoG was performed on 18 normal ears, 22 Menière's ears and 14 ears with cochlear type sensorineural hearing loss other than Menière's disease. Although the Menière's ears had larger mean summating potential (SP) than the normal ears, the difference between both groups was not statistically significant. The mean amplitude and latency of the action potential (AP) in Menière's ears decreased and elongated significantly, but neither was sensitive enough in diagnosing Menière's disease. The SP/AP amplitude ratio not only made significant difference among 3 groups, but also had good diagnostic sensitivity (59.1%) and specificity (92%) in diagnosing Menière's disease while using the 95% upper confidence limit of the normative data (i.e., 34%). The SP/AP amplitude ratio of Menière's ears tended to increase while the mean hearing level of 4-8 KHz deteriorated. Also, abnormal enlargement of the SP/AP amplitude ratio in Menière's disease tended to be the result of decreased AP amplitude.