Bilateral vestibular failure is a rare condition characterized by severely reduced or absent function of both vestibular nerves. It is also called bilateral vestibular loss, bilateral vestibular weakness, or bilateral vestibulopathy.
The most common cause of bilateral vestibular failure is the usage of aminoglycoside antibiotics like gentmicin, tobramycin and streptomycin, which can damage the inner ears. Bilateral Meniere’s disease, autoimmune inner ear disease, and damage to the vestibular nerves from meningitis may also cause bilateral vestibulopathy but are uncommon. Some neurodegenerative diseases like multiple system atrophy, and CANVAS (Cerebellar Ataxia Neuropathy Vestibular Areflexia Syndrome) may also cause bilateral vestibular failure. Very rare causes include bilateral vestibular neuritis, superficial siderosis, syphilis, and bilateral vestibular schwannomas. In some, the cause is unknown (idiopathic).
Bilateral vestibular failure tends to occur in adults over age 60. Symptoms include imbalance, and oscillopsia or blurry vision with head movement. The diagnosis can be ascertained by the bedside examination of the vestibulo-ocular reflex, and confirmed with rotatory chair testing and caloric or video head impulse testing. Hearing loss may or may not accompany bilateral vestibular failure.
Unfortunately, bilateral vestibular failure appears to be a difficult condition to treat. Stopping any medications that are toxic to the vestibular apparatus is obvious. Vestibular therapy, and exercises that improve eye-head coordination (e.g. ping-pong, tennis, pickleball) can help improve the symptoms.