Female 26 years old with history of osteosarcoma of the right femur with pulmonary and right cerebellar mets s/p resection and CTX, evaluate tumor progression Exam is motion degraded limiting evaluation for small lesions. Again seen are posttreatment changes including right occipital craniotomy for right cerebellar lesion resection. Compared to multiple prior studies dating back to 7/8/2015, there is increase in nodular enhancement along the posterior margin of the resection cavity, which involves the craniotomy defect and measures approximately 19 mm AP x 6 mm transverse x 8 mm CC dimension. The cystic component of the resection cavity demonstrates decreased size/collapse, which is consistent with expected evolution of post-surgical changes. No new focus of parenchymal edema or new enhancing lesions are identified within the limitations of the motion degraded study. Subtle T2/FLAIR signal surrounding the resection bed suggestive of gliotic changes as well as foci of susceptibility suggestive of remote post-surgical blood products.There is no evidence of acute intracranial hemorrhage or restricted diffusion to suggest acute infarct. The ventricles and basal cisterns are normal in size and configuration. There is no midline shift or herniation. The major cerebral flow voids are intact. The orbits, skull, paranasal sinuses, and scalp soft tissues demonstrate no gross abnormality.
Slight increase in nodular enhancement along the posterior margin of the right cerebellar resection cavity. Given history of recent radiation, findings may represent post therapy changes or evolving postsurgical granulation tissue at the craniotomy bed. Recommend continued close attention on follow-up. No new lesions elsewhere in the brain parenchyma to definitively suggest progression.