Diagnostic Role of Combined Electrocochleography and Pure-Tone Audiometry Monitoring During Dehydrating Test in Ménière's Disease: A Case Series

Objectives: To evaluate the diagnostic role of combined electrocochleography and pure-tone audiometry monitoring during dehydrating test in Ménière's disease and consider its suitability as a diagnostic tool to differentiate those patients with unclear differential diagnosis and therefore identify those with clear endolymphatic hydrops responsive to dehydrating test. To study the efficacy of dehydrating therapy on vertiginous symptoms and hearing loss in patients with Ménière's disease. Study design: Prospective case series. Settings: University hospital, secondary referral center. Patients: Thirty patients, 20 women and 10 men, age range of 25 to 75 years, matching the criteria for definite Ménière's disease according to the Barany Society classification. Intervention: Diagnostic. During an active phase of the disease, electrocochleography and pure-tone audiometry were performed, and repeated at 30th, 45th, and 60th minutes after intramuscular injection of 40 mg furosemide and 40 mg methylprednisolone. Main outcome measure: Data related to symptoms, electrocochleography, and pure-tone audiometry during the dehydrating test were collected at different times and statistically analyzed. Results: After the administration of dehydrating therapy, we observed that both summating potential and action potential ratio and summating potential and action potential area ratio were normalized in 21 of 30 subjects. Furthermore, pure-tone audiometry thresholds improved significantly. An improvement of ear fullness was also observed, whereas tinnitus unchangeably persisted. Conclusions: The monitoring of the electrocochleography and pure-tone audiometry thresholds during dehydrating tests with furosemide and methylprednisolone could allow to detect an improvement of instrumental features and clinical symptoms related to endolymphatic hydrops, and therefore, it could be used as a diagnostic tool in the identification of those patients affected by Ménière's disease with unclear differential diagnosis.