OCULAR AND CERVICAL VESTIBULAR EVOKED MYOGENIC POTENTIALS IN MULTIPLE SCLEROSIS PATIENTS

Multiple sclerosis (MS) is a serious, debilitating disease of the central nervous system, and is a leading cause of disability at a young age. The purpose of this study is to evaluate the vestibular system in patients with MS, by using ocular vestibular evoked myogenic potentials (oVEMPs) and cervical vestibular evoked myogenic potentials (cVEMPs). Twenty-five patients diagnosed with MS and 25 healthy controls participated in the study. The main duration of the disease of the patients was 12.3 +/- 9.2 years and the median score of EDSS was 2.5. Thirty-six percent of all patients had brainstem lesions evident on MRI scans. In 24% of all patients vestibular symptoms were observed. All patients had bilateral cVEMP and oVEMP responses. No significant differences between left and right side mean values of the examined subjects (patients and controls) for all parameters of cVEMP and oVEMP responses were detected. No significant differences between oVEMP parameters of MS patients and controls were observed. The relative amplitudes of cVEMPs were significantly lower than those in the healthy controls. Compared to healthy controls, the patients with MS showed prolonged mean latencies for cVEMPs for p13 and n23 waves, but significant differences between the two groups were not observed. Significant positive correlations between the severity of disability (evaluated by EDSS), and the latencies of p13 and n23 waves, and negative correlations between disability and relative amplitudes of cVEMPs of MS patients were found. The VEMP tests are reliable, non-invasive, objective, and easy-to-use for detecting subclinical lesions of the vestibular neuronal paths, and can be helpful in the diagnosis and follow-up of patients with MS.