Anaplastic oligodendroglioma, WHO grade III status post treatment: surveillance. There are postoperative findings related to subtotal right frontal tumor resection, with a 5 mm wide extra-axial residual fluid collection anteriorly. There is interval increase in size of heterogeneously enhancing tumor with punctate foci of susceptibility effect along the resection cavity margins, which measures up to approximately 35 mm in thickness. There is also increased extensive surrounding non-enhancing confluent T2 hyperintensity with up to approximately 10 mm of midline shift to the left, as well as subfalcine herniation and partial effacement of the right lateral ventricle. There is no acute territorial infarct. The major cerebral flow voids are intact. The orbits are grossly unremarkable.
Postoperative findings related to subtotal right frontal tumor resection with interval increase in size of tumor along the surgical margins, as well as the extensive surrounding edema and/or non-enhancing tumor infiltration with approximately 10 mm of midline shift.