Pilocytic astrocytoma of the cerebellopontine angle in a child presenting with auditory neuropathy spectrum disorder.

Auditory neuropathy spectrum disorder (ANSD) is a clinical syndrome with hearing loss characterized by measurable otoacoustic emissions (OAEs) and absent or abnormal brain stem evoked response audiometry findings (BERA) (1,2). Routine magnetic resonance imaging (MRI) has been advocated in children with ANSD because cochlear, neural, or central abnormalities are observed in up to 64% of affected cases (2). In the two largest reported imaging series comprising a combined total of 221 children, developmental malformations, such as cochlear nerve deficiency or hindbrain malformations, were predominantly observed, suggesting a benign origin of ASND in general. Bilateral ANSD cases are approximately 4 times more frequently associated with intracranial abnormalities compared with unilateral cases (2). In contrast, unilateral ANSD should remind the reader of tumor growth in the cerebellopontine angle (CPA), as previously reported in a single case (3) and with the presented case below.