[Value of auditory evoked potentials and electrocochleography in the diagnosis of small acoustic neuromas. Our experience on 131 cases].

The auditory brainstem responses, in a series of 131 patients with surgically confirmed acoustic neuroma, are reported. Six groups have been individualized according to the value of the I-V interpeak latency, the synchronisation of the waveform shape and the need to perform an electrocochleography. If we exclude the sixteen cases of profoundly deafness, or cophosis, where ABR and ECoG don't permit the recording of waves, the electrophysiological investigations allowed to provide the diagnosis of retrocochlear lesion in 115 patients, for a rate of 98.26%. This high degree of sensitivity favorably with data reported in literature, and supports the reliability of this method for detection of acoustic neuroma. According to these results, our diagnosis workup of a patient suspected of having an acoustic neuroma, presenting normal ABR findings, is presented.