Diagnostic significance of electrocochleogram and auditory evoked brainstem response in totally or subtotally deaf patients.

This paper examined the use of ECoG and ABR in 7 patients with totally or subtotally deaf ears. The patients included one with cortical deafness, one with psychogenic deafness, one with intrapontine hemorrhage, and 4 with acoustic neuroma. In patients with substantial hearing loss, ECoG should be performed first if retrocochlear disorders are suspected since results may be obtained even in the absence of other auditory evoked potentials. Simultaneous ABR measurements can be effective when localizing retrocochlear lesions. ECoG can also help to determine the need for preserving hearing during surgery for retrocochlear lesions by indicating the degree of cochlear function.