A prospective study was carried out to establish the utility of Auditory Middle Latency Response (AMLR) in the evaluation of patients with relapsing- remitting multiple sclerosis. Twenty subjects were evaluated with the multimodal battery of auditory, visual and somatosensory evoked potentials, AMLR, and motor evoked potential by transcraneal magnetic stimulation. The results showed the following abnormalities: 60 % in the AMLR, (only 50 % of them with clinical symptoms), 25% in the auditory brainstem response, 85 % in the visual response and 90 % in somatosensorial and motor potentials. We found significant differences between the auditory tests and the rest of the electrophysiological techniques (rate comparison, p<.05). Those differences disappeared when auditory tests were considered together. There was a significant association between anatomical and functional tests in the evaluation of the auditory pathway, and a positive correlation between the absolute latency of Na, Pa, and Pb components and the temporal course of the disease. The results suggest the convenience of including AMLR in the battery of evoked potentials for the study of relapsing- remitting multiple sclerosis patients.
