Lesion site in idiopathic bilateral vestibulopathy: a galvanic vestibular-evoked myogenic potential study.
CONCLUSIONS
The result suggests that patients with idiopathic bilateral vestibulopathy may have nerve lesions when the inferior nerve system is affected, while the inferior vestibular nerve system may be spared.


OBJECTIVE
To clarify the lesion site in idiopathic bilateral vestibulopathy, an acquired bilateral vestibulopathy of unknown cause.


METHODS
Two 75-year-old males diagnosed with idiopathic bilateral vestibulopathy were enrolled. Both showed absent or highly decreased responses on the caloric test on both sides. They underwent vestibular-evoked myogenic potential (VEMP) testing by means of acoustical and electrical stimulation. As acoustic stimulation, 95 dB nHL clicks and short tone bursts (500 Hz) were presented, while 3 mA (1 ms) short-duration galvanic stimuli were presented as electrical stimulation. Responses were recorded on the sternocleidomastoid muscles.


RESULTS
Both patients showed unilateral absence of VEMPs with both acoustic and short-duration galvanic stimuli.
Fujimoto
Chisato
C
Department of Otolaryngology, University of Tokyo, Fujimi, Tokyo, Japan.
Iwasaki
Shinichi
S
Matsuzaki
Masaki
M
Murofushi
Toshihisa
T
D000161:Acoustic Stimulation; D000368:Aged; D001301:Audiometry, Pure-Tone; D004244:Dizziness / Q000175:diagnosis / Q000503:physiopathology; D004292:Dominance, Cerebral / Q000502:physiology*; D004558:Electric Stimulation; D019054:Evoked Potentials, Motor / Q000502:physiology*; D006801:Humans; D008297:Male; D009334:Neck Muscles / Q000294:innervation*; D011304:Presbycusis / Q000175:diagnosis / Q000503:physiopathology; D014012:Tinnitus; D014724:Vestibular Function Tests; D020338:Vestibular Neuronitis / Q000175:diagnosis* / Q000503:physiopathology