Reason: Eval autoimmune vs neoplastic lesion. History: abnml brain MRI.. There is a heterogeneous left frontal lesion which exhibits high T2 signal and scattered areas of susceptibility. A small cyst within the lesion is unchanged. T2 abnormality extends across the genu of the corpus callosum and into the left temporal lobe, similar in extent to prior exams. There may be some very mild patchy nonmass-like enhancement within the lesion along with intrinsic T1 hyperintensity, all unchanged. Perfusion imaging shows areas of both elevated and diminished perfusion within the affected parenchyma. A left frontal burr hole is unchanged. 4 mm of left to right shift is unchanged. Mass effect with effacement of the left frontal horn appears similar to the prior exam. The major cerebral flow voids are intact. The orbits, skull, and scalp soft tissues are grossly unremarkable. Bilateral mucous retention cysts/polyps.
Heterogeneous, chronically injured parenchyma in the left frontal lobe is not significantly changed from prior exams.