82 years, Female, metastatic non-small lung cancer status post SRS to the left frontal lesion. Evaluate for interval growth vs necrosis and also the left parietal focus. Unchanged size of left frontal lobe enhancing lesion measuring 15 x 15 x 14 mm, although with increased thickness of the rind of peripheral enhancement and decreased extent of central enhancement. There is now also associated restricted diffusion. There is adjacent T2 hyperintense vasogenic edema, which is decreased in extent especially cranially with overall decreased gyral/parenchymal enhancement. There are no new enhancing lesions. There is no midline shift or herniation. There is a small focus of likely chronic hemosiderin within the superior right frontal lobe. The ventricles are within normal limits in size and configuration. Several foci of nonspecific T2/FLAIR hyperintensity are seen in the bilateral subcortical and periventricular white matter, similar to prior. Left occipital white matter T2/FLAIR hyperintense focus has resolved. A left cortical parietal focus of enhancement adjacent to the intraparietal sulcus is no longer appreciated. Major flow-voids are preservedThere is fluid within the left mastoid air cells.
Given unchanged overall size of the enhancing left frontal lobe lesion and significantly decreased extent of surrounding white matter FLAIR hyperintensity and parenchymal expansion, although with slight increased thickness of the lesion's enhancing rim and new diffusion restriction, finding is favored to relate evolving post-treatment changes.Previously seen left parietal cortical punctate focus of enhancement has resolved.