Cervical Vestibular Evoked Myogenic Potentials in Cerebellar Lesions

Introduction: Reports about cervical vestibular evoked myogenic potentials (cVEMPs) in central nervous system lesions are scarce. Our experience with cerebellar lesions is still evolving, with only a few cases published. The purpose of this article is to present our cVEMP findings of 3 cases with cerebellar lesions. Materials and Methods: cVEMPs were performed using unilateral 120-dB peak SPL intensity 1 kHz tone air-conducted sound stimulation with contralateral masking noise, with recording from the tonically active sternocleidomastoid muscle. Results: Brain MRI scans showed a small focal lesion in the right middle cerebellar peduncle in our first case, 2 foci in the right middle cerebellar peduncle and cerebellar hemisphere in our second case, and lesions in the right superior and inferior cerebellar peduncles near the fourth ventricle in our final case. All cVEMPs were normal. Discussion: cVEMPs seem to be unaffected by at least certain cerebellar peduncle and hemispheric lesions. Although an abnormal cVEMP result may suggest noncerebellar dysfunction, further work is needed, as the lesions reported may not be interrupting the known cerebellovestibular pathways. Normal cVEMP responses may also or otherwise be due to affected vestibular nuclei influenced by the above cerebellar lesions not being part of the cVEMP pathway.