Misdiagnosis of otosclerosis in a patient with enlarged vestibular aqueduct syndrome: a case report

A Large Vestibular Aqueduct With Conductive Hearing Loss as the Only Manifestation

Conductive hearing loss is a common clinical condition caused by disorders of the middle and external ear. Here, we report a case of conductive hearing loss with complete tympanic membranes. Clinical examinations revealed no external and middle ear lesions, but high-resolution temporal bone computed tomography revealed enlarged vestibular aqueducts. Detailed audiological tests and follow-up results indicate that the exclusive air-bone gap is the outcome of inner ear malformation but not middle ear lesions, preventing the need for tympanic assessment.

Unilateral Enlarged Vestibular Aqueduct Syndrome and Bilateral Endolymphatic Hydrops

Enlarged vestibular aqueduct (EVA) syndrome is a common congenital inner ear malformation characterized by a vestibular aqueduct with a diameter larger than 1.5 mm, mixed or sensorineural hearing loss that ranges from mild to profound, and vestibular disorders that may be present with a range from mild imbalance to episodic objective vertigo. In our study, we present the case of a patient with unilateral enlarged vestibular aqueduct and bilateral endolymphatic hydrops (EH). EH was confirmed through anamnestic history and audiological exams; EVA was diagnosed using high-resolution CT scans and MRI images. Therapy included intratympanic infusion of corticosteroids with a significant hearing improvement, more evident in the ear contralateral to EVA. Although most probably unrelated, EVA and EH may present with similar symptoms and therefore the diagnostic workup should always include the proper steps to perform a correct diagnosis. Association between progression of hearing loss and head trauma in patients with a diagnosis of EVA syndrome is still uncertain; however, these individuals should be advised to avoid activities that increase intracranial pressure to prevent further hearing deterioration. Intratympanic treatment with steroids is a safe and well-tolerated procedure that has demonstrated its efficacy in hearing, tinnitus, and vertigo control in EH.

Enlarged vestibular aqueduct syndrome mimicking otosclerosis in adults

INTRODUCTION

An enlarged vestibular aqueduct (EVA) results in hearing loss which is often progressive and heterogenous, the long-term natural history of which is not well understood. Patients born before the era of newborn hearing screening can present as adults with previously undiagnosed EVA.

METHODS

A retrospective chart review of patients seen at a tertiary adult academic otologic clinic from 2004 to 2012 were reviewed and cases of EVA were identified.

RESULTS

Adult EVA was found to present with a mixed progressive hearing loss with absent stapedial reflexes.

CONCLUSION

Enlarged vestibular aqueduct abnormality can present in adulthood and mimic other more common pathology such as otosclerosis.