69 years, Male, status post craniotomy for GBM resection. Weakness. Evaluate for new infarct or another new lesion. Again seen are postsurgical changes of left parietal craniotomy for tumor resection. Again seen is nodular enhancement involving the anterior medial and anterior inferior aspects of the resection cavity including the left parietal and posterior frontal lobes which appears more prominent than on prior. There is restricted diffusion surrounding the postoperative resection cavity compatible with cytotoxic edema/infarct which shows mild evolution. There is no new infarct elsewhere in the brain. There is also interval increase in FLAIR hyperintensity surrounding the resection cavity which has increased since postoperative study from 9/29/2015. Small extra-axial collection beneath the left parietal craniotomy is again seen with evolution in signal intensity of the blood products. There is no midline shift or herniation. No hydrocephalus.
Compared to postoperative MRI from 9/29/2015, there has been evolution of postoperative changes including of the small areas of cytotoxic edema/infarct surrounding the left parietal resection cavity. There is interval increase in nodular enhancement surrounding the resection cavity, particularly in its anterior medial and anterior inferior aspects, as well as increase in FLAIR hyperintensity surrounding the resection cavity. These changes may represent evolution of postsurgical changes and mildly worsened edema but early tumor progression cannot be excluded. Suggest close follow-up evaluation.