Epidermoid

There is a heterogeneous T1 hypointense, T2 hyperintense, non-enhancing lesion which demonstrates restricted diffusion centered in the left middle cranial fossa with adjacent post-surgical changes and extension into the temporal horn of the left lateral ventricle and the left lateral aspect of the suprasellar and prepontine cisterns. The mass incompletely suppresses on T2 FLAIR. Signal characteristics are classic for an epidermoid. Most epidermoids are intradural and commonly involve the basilar cisterns. They tend to follow the signal of CSF, but do not completely suppress on FLAIR. Diffusion restriction is the defining imaging feature. Treatment is with surgical resection.