Vertigo and the enlarged vestibular aqueduct syndrome

An enlarged vestibular aqueduct (EVA) is one of the most commonly identifie d inner ear bony malformations in children with sensorineural hearing loss of unknown cause. Most previous reports have focused on hearing loss, but i ndividuals with EVA may also experience paroxysmal vertigo lasting minutes to hours. We report the clinical vestibular features and vestibular functio n testing of two children and one adult with EVA who had a history of senso rineural hearing loss and presented to our Neurotology Clinic for the evalu ation of episodic vertigo. All the patients had an antecedent history of pr ofound bilateral sensorineural hearing loss that had been present since ear ly childhood. The onset of vertigo was delayed into adulthood in one patien t. Episodes of vertigo could be triggered by minor head trauma or vigorous physical activity. Despite recurrent episodes of vertigo, vestibular functi on was normal or moderately impaired compared with the severe auditory defi cit. Careful analysis of temporal bone CT demonstrated EVA. Associated enla rgement of the membranous endolymphatic sac was evident on brain MRI. While hearing loss is a prominent symptom in patients with EVA, vestibular sympt oms may cause referral to a neurologist. Although hearing loss occurs early in childhood, vestibular symptoms can be delayed into adulthood, a finding not previously reported.