Brainstem auditory evoked potentials in patients with multi-infarct dementia and dementia of the Alzheimer type.

Brainstem auditory evoked potentials (BAEPs) were recorded in 25 patients with multi-infarct dementia (MID) (mean age 71.2 years), 16 patients with dementia of the Alzheimer type (DAT) (mean age 70.6 years), and 34 normal subjects (mean age 69.1 years). Both MID and DAT patients showed significant prolonged interpeak latencies between waves I and V (I-V IPLs) compared to normal subjects (p less than .001 and p less than .01, respectively). In patients with MID, both I-III IPLs and III-V IPLs were significantly longer than those of normal subjects (p less than .01 and p less than .01 respectively). On the other hand, only III-V IPLs were significantly prolonged in patients with DAT (p less than .01). There were no significant differences between MID and DAT with regard to any of the IPLs. Present results suggest that the brainstem lesions are located in the auditory pathways in patients with MID and DAT. However, with BAEP measurements, we were not able to discriminate between patients with MID and DAT.