Multicystic acoustic neuroma. Case report and differential diagnosis.

A rare case of a multicystic acoustic neuroma is reported. At computed tomography (CT) and magnetic resonance imaging (MRI) the tumor was found to cause hydrocephalus, and displacement of the brainstem. The multicystic character was revealed on CT, while MRI only showed the mass lesion and the common signal intensities for an acoustic neuroma. The differential diagnosis of a multicystic lesion in the cerebellopontine angle is discussed.