Atypical manifestation of vestibular schwannoma

Abstract

Introduction Vestibular schwannoma (also known as acoustic neuroma) is a benign tumor whose cells are derived from Schwann sheaths, which commonly occurs from the vestibular portion of the eighth cranial nerve. Furthermore, vestibular schwannomas account for ∼8% of intracranial tumors in adults and 80 to 90% of tumors of the cerebellopontine angle. Its symptoms are varied, but what stands out most is a unilateral sensorineural hearing loss, with a low index of speech recognition. Objective Describe an atypical manifestation of vestibular schwannoma. Case Report The 46-year-old woman had vertigo and binaural hearing loss and fullness, with ear, nose, and throat examination suggestive of cochlear injury. After 6 months, the patient developed worsening of symptoms and onset of right unilateral tinnitus. In further exams the signs of cochlear damage remained, except for the vestibular test (hyporeflexia). Magnetic resonance imaging showed an expansive lesion in the right cerebellopontine angle. Discussion This report warns about the atypical manifestations of vestibular schwannoma, which must always be remembered in investigating and diagnosing hearing loss.

Keywords: acoustic; dizziness; hearing loss; neuroma.

Fig. 1

Magnetic resonance imaging showing lesion occupying the entire length of the right internal auditory canal (5 × 6 × 14 mm) with lateral margin establishing contact with the bottom of the canal and labyrinth without extension.