Transtympanic electrocochleography in evaluation of cochleovestibular disorders

We examined the electrocochleography (ECochG) parameters in patients suffering from Meniere's disease (n = 5) or other type of vertiginous disorder (n = 4). Fourteen ears were examined by introducing a needle electrode through the tympanic membrane to the promontorium. The summating potential (SP), action potential (AP) and the SP/AP ratio were measured from the alternating polarity click response, and the latency difference from the condensation and rarefaction click responses. These 2 patient groups differed from each other most clearly as to the audiometry results and the duration of symptoms. We also found differences in electrocochleographic results, especially in latency differences between the condensation and rarefaction click responses. Although the present material is small we conclude that transtympanic electrocochleography is a sensitive method to measure cochlear potentials, and might be a valuable addition in diagnosing patients suffering from various cochleovestibular disorders.