Clinical usefulness of extratympanic electrocochleography in the diagnosis of Ménière's disease

Objective: Electrocochleography has been introduced to aid the diagnosis of endolymphatic hydrops. The aim of this study was to evaluate the clinical effectiveness of extratympanic electrocochleography in the diagnosis of Ménière's disease. Study Design: The medical records of patients diagnosed as having Ménière's disease at the department of otolaryngology were reviewed retrospectively. Thirty-seven healthy ears were included to calculate the upper level of the 95th percentile range of the extratympanic electrocochleography variables. Setting: Tertiary referral university hospital. Patients: One hundred fifty-eight patients (97 women and 61 men) diagnosed as having Ménière's disease without previous treatments were included. A retrospective analysis of their medical records, electrocochleographic results, audiograms, and follow-up records was performed. The mean age was 48.6 years. Main Outcome Measures: The upper level of the 95th percentile range of the extratympanic electrocochleography variables of normal subjects were calculated. Electrocochleography recording results were compared with the diagnostic scale and stage, presence of fluctuating hearing loss, and duration of symptoms. Results: The 95% upper limit for baseline summating potential and action potential ratio was 0.34. Sensitivity and specificity of electrocochleography in the diagnosis of Ménière's disease were 71% and 96%, respectively. The results statistically correlated with the Ménière's current diagnostic criteria and did not correlate with the stage of disease, presence of fluctuating hearing loss, or duration of symptoms. Conclusion: Extratympanic electrocochleography may play an important role, especially in patients with less definite symptoms, but the diagnosis should also be anchored in the patient's clinical history, symptoms, and audiogram.