A sharply circumscribed 3.9 x 4.7 x 3.7 cm left posterior inferior frontal mass approaches CSF signal on most sequences, with areas of ill-defined incomplete flair suppression. The presence of marked diffusion restriction in the lesion is characteristic of an epidermoid.
Mass effect effaces and displaces superiorly and to the right the left frontal horn, and causes subfalcine herniation of the left inferior frontal parenchyma. The mass extends posteriorly to the level of the foramen of Monro, which is partially effaced but not obstructed. Faint linear enhancement about the periphery of the mass.
Minimal surrounding gliosis or oedema.
A few small T2 hyperintense white matter foci compatible with mild age-related change chronic small vessel ischaemia. No parenchymal susceptibility artefact. No further mass lesion or pathological contrast enhancement. No hydrocephalus.
Conclusion: Large left frontal epidermoid.