[Diagnostic value of brainstem auditory evoked potentials (author's transl)].

The present work is an evaluation of brainstem auditory evoked potentials (BAEP) as a tool for neurological diagnosis. Filtered alternate clicks with monaural stimulation and ipsilateral recording between the vertex and the ipsilateral mastoid have been used. Normative data of the laboratory established in 50 normal subjects, mean age 35 years, and criteria for interpretation are given. 155 patients had or were suspected of having multiple sclerosis. In definite multiple sclerosis (33 patients), BAEP were abnormal in 67 p. 100 of the cases, among them the 4 patients with an internuclear ophtalmoplegia. In probable multiple sclerosis (54 patients) BAEP were abnormal in 41 p. 100 of the cases and in possible multiple sclerosis (68 patients) there were 19 p. 100 with abnormalities. Results show that BAEP are clearly a useful tool for diagnosis in progressive paraplegia, in optic neuritis, and in cases in which symptoms and signs lead to discuss posterior fossa tumours. In 66 patients with suspected or proved tumours (acoustic neurinomas excluded) and in 25 patients with vascular disease, the contribution of BAEP to neurological diagnosis is of unequal interest. In some cases BAEP only confirmed the data of the clinical examination. When tumours were diagnosed with the CT scan, BAEP could help in pointing out the accurate relation of the tumour with the brainstem and the auditory pathways. In 36 patients the contribution of BAEP was important in establishing the rostral extension of bulbocervical tumours or, mainly, in indicating the presence or absence of infiltrating brainstem tumours which were not clearly apparent on the CT scan.