Vector analysis of brain-stem auditory evoked potentials in patients with multiple sclerosis and subtentorial tumors.

Vector analysis of BAEPs was done in 10 patients with posterior fossa tumors and 14 patients with MS. Latency abnormalities were found in both groups without significant differences. However, deviations of wave V vectors from its normal orientation were observed in tumor cases, correlated with tumor size and latency increase. It is concluded that vector deviations may indicate distortion of auditory pathways in the brain-stem.