Brainstem representation of vestibular evoked muscle potentials

Vestibular evoked muscle potentials (VEMPs) are caused by a short-latency reflex recorded from averaged electromyography from the sternocleidomastoid muscle evoked by intense auditory clicks stimulating the sacculus. Besides peripheral vestibulopathy, abnormal VEMPs can be caused by lesions of the brainstem. 29 patients with brainstem infarcts were prospectively analyzed using VEMPs and MR imaging to evaluate the brainstem representation of the VEMP reflex. 12 patients showed unilaterally abnormal VEMPs, 10 patients had normal VEMPs. 7 patients with unspecific bilaterally absent VEMPs were not analyzed. Individu…