Presentation
Right hearing loss.
Patient Data
A large, well-defined extra-axial mass at the right cerebellopontine angle enlarges the porus acusticus with intracanalicular extension. It elicits a low signal on T1, heterogeneous high signal on T2 and FLAIR with cystic areas of high signal. The postcontrast sequences show a heterogeneous enhancement of the solid component.
A mass effect is noted on the right middle cerebellar peduncle, brainstem, 4th ventricle and the cisternal portion of the trigeminal nerve, and the cerebellar hemisphere with mild dilatation of the 3rd and lateral ventricles.
Case Discussion
MRI features most consistent with acoustic neuroma of right CPA with intracanalicular extension, compressing the middle cerebellar peduncle, brainstem, cerebellar hemisphere, cisternal portion of the trigeminal nerve, and 4th ventricle with a mild secondary obstructive hydrocephalus.