Ocular and cervical vestibular evoked myogenic potentials in patients with multiple sclerosis.

OBJECTIVES The aim of this study was to evaluate latencies and corrected p13-n23 cervical vestibular evoked myogenic potentials (cVEMP) and n10-p13 ocular vestibular evoked myogenic potentials (oVEMP) amplitudes in patients with relapsing remitting multiple sclerosis (MS). METHODS This was a prospective, case-control study. Thirty patients with MS and 15 healthy controls were included. Cervical vestibular evoked myogenic potentials and oVEMP in response to acoustic clicks of 1 ms duration at the intensity of 130 dB SPL and the stimulation frequency of 1 Hz were studied. Signals were divided in segments of 120 ms duration (20 ms before the stimulus and 100 ms after the stimulus) and averaged. RESULTS In MS group, there was significant latencies prolongation of all sternocleidomastoid responses (p13 and n23) and n10 response of the ocular muscles. The sternocleidomastoid p13-n23 normalized amplitude was significantly higher in MS patients. Prolonged latencies were found in 57% and conduction block in 7% of patients in at least one sternocleidomastoid response in the MS group. Prolonged latencies were found in 30% and conduction block in 40% of patients in at least one ocular response in the MS group. When cVEMP and oVEMP are combined, 80% had pathological finding. When correlating brainstem clinical, brainstem MRI, and cVEMP findings, there was no statistical significance (brainstem clinical vs. cVEMP P = 0.1; brainstem MRI vs. cVEMP P = 0.82). When correlating brainstem clinical, brainstem MRI and oVEMP findings, there was a statistical significant correlation between brainstem clinical versus oVEMP, P = 0.02, whereas there was no statistical significance between brainstem MRI versus oVEMP (P = 0.38). CONCLUSIONS Combination of cVEMP and oVEMP in MS patients allows better estimation of brainstem lesions.