Diagnostic value of vestibular-evoked myogenic potentials in Ménière's disease and vestibular migraine.

Overlaps can be seen between vestibular migraine (VM) Ménière's Disease (MD) and diagnosis is difficult if hearing is normal. We aimed to investigate the sacculo-collic pathway in VM patients, MD patients, and healthy controls to define the diagnostic role of cervical VEMP (cVEMP). VEMP testing in response to 500 Hz and 1000 Hz air-conducted tone burst (TB) stimulation was studied prospectively in 22 subjects with definite VM (according to Bárány nomenclature), 30 subjects with unilateral definite MD, and 18 volunteers matched healthy controls. In VM subjects, response rate, p13 and n23 latencies were similar to healthy controls, but peak-to-peak amplitudes were bilaterally reduced at 500 Hz TBs (p= 0.005). cVEMP differentiated MD patients from VM and healthy controls with asymmetrically reduced amplitudes on affected ears with low response rates at 500 Hz TBs, and alteration of frequency dependent responses at 500 and 1000 Hz TBs. These findings suggest that cVEMP can be used as a diagnostic test to differentiate MD from VM. On the other hand, VEMP responses are symmetrically reduced on both sides in VM patients, suggesting that otolith organs might be affected by migraine-induced ischemia.