Imaging diagnosis--intracranial epidermoid cyst in a Doberman Pinscher.

A 4-year-old Doberman Pinscher was evaluated for chronic progressive central vestibular disease and aggressiveness. A cyst-like lesion was identified in the region of the left cerebellopontine angle. The lesion was hypointense on T1-weighted and hyperintense on T2-weighted images. Differentials included an epidermoid or dermoid cyst, cystic neoplasm, and brain abscess. Hyperintensity on subsequent fluid-attenuated inversion recovery images excluded an arachnoid cyst. The histopathologic diagnosis was epidermoid cyst within the fourth ventricle.