Epidermoid of the lateral ventricle: evaluation with diffusion-weighted and diffusion tensor imaging.

We report of a large epidermoid tumor of the lateral ventricle in a 67-year-old man. Conventional imaging (CT, T1/T2, MRI) could not differentiate the tumor from the surrounding cerebral spinal fluid (CSF). On diffusion-weighted and diffusion anisotropy images the tumor was clearly seen as a hyperintense mass surrounded by hypointense CSF, highly suspected for epidermoid.