Follow-up of brain abnormality that was nonspecific by a previous biopsy. The well-circumscribed lesion involving the left caudate head and the anterior part of the left globus pallidus as well as the intervening anterior limb remains unchanged since July 2015 in size and continues to show relatively angular margins. It is more homogeneously T2-hyperintense and heterogeneously T1-hypointense. The associated contrast enhancement on the medial, subependymal aspect of the lesion is decreased but is associated with mild linear focal diffusion restriction. The remainder of the involved left dorsal striatum is atrophic and there continues to be ex vacuo enlargement of the adjacent portions of the left lateral ventricle. Associated susceptibility effect remains minimal with also a small adjacent traversing vessel. Otherwise, there is no acute infarct, acute hemorrhage or mass-effect. The remainder of the CSF-containing spaces remains normal size. There is no brain herniation.Multiple small T2-hyperintense lesions are present in a subcortical distribution in the left cerebral hemisphere, and to lesser extent the right cerebral hemisphere. The corpus callosum is spared as well as the posterior fossa structures.The major intracranial vascular flow voids are preserved. There is minimal fluid intensity in the left mastoid air cells and trace sphenoethmoid mucosal thickening.
1.The left dorsal striatum lesion shows less contrast enhancement and probably more cavitation. It continues to show volume loss rather than mass-effect and is well-circumscribed with angular margins. This may reflect slow evolution of an inflammatory lesion but the findings are nonspecific otherwise.2.Few subcortical white-matter lesions involving both cerebral hemispheres, more pronounced on the left, are nonspecific but might be ischemic in nature. 