Vestibular evoked myogenic potential in a child with multiple sclerosis

Abstract

Vestibular evoked myogenic potential (VEMP) is a short-latency electromyographic response elicited by acoustic stimuli and is recorded from tonically contracted neck muscles, particularly the sternocleidomastoid muscle (SCM). This potential is used to diagnose lesions of the saccule, inferior vestibular nerve, and vestibulospinal tract. Our case involved a 15-year-old girl whose chief complaints were dizziness and an eyeball abnormality. The left side stimulation showed waveform loss in the examination of VEMP. MRI revealed a T2WI hyperintense area in the left ventral and right dorsal parts of the pons, and a lesion was observed in the cerebral white matter during a follow-up examination. The regions examined in the VEMP test included the nuclei vestibulares, which is located in the dorsal part of the pons and medulla oblongata; the MRI findings for the same region did not concur with the results of the VEMP test. This VEMP test detected dysfunction of the vestibular nucleus or the vestibulospinal tract, which was thought to indicate a lesion that was undetectable by MRI.