43 year-old right-handed male with recurrent GBM, WHO grade IV, IDH1 R132H mut, ATRX wt, s/p outside resection on 3/7/2016; compare to prior MRI on 4/28/16; currently s/p 2 cycles of IDO immunotherapy plus TMZ There are post-surgical findings of a right-sided craniotomy with removal of a right inferior parietal lobule and adjacent temporal lobe mass. The resection cavity is CSF signal intensity with surrounding siderosis appearing less prominent compared to prior exam. There is a small linear focus of enhancement along the superior aspect of the resection cavity, which may represent granulation tissue or a vessel. There are multiple scattered tiny enhancing nodules along the resection cavity appearing similar to prior exam. The previously described more heterogeneous prominence along the inferolateral aspect of the resection cavity appears decreased in thickness, with the hypo-enhancing central component no longer visualized.There are more conspicuous nodules now noted along the posterior aspect of the right thalamus extending laterally to the resection cavity, which do not demonstrate increased perfusion. However, on coronal images which are the best direct comparison, there is now a triangular-shaped area of enhancement along the lateral aspect of the unroofed portion of the right lateral ventricle, which demonstrates hyperperfusion and appears more confluent and conspicuous on this exam. This appears band-like on axial images, with increased extent of associated FLAIR hyperintensity. Additional areas of new linear enhancement along the right posterior body of the corpus callosum with extension along the right fornix as well as the left splenium/ependymal surface and right occipital horn lateral ependymal surface are also noted and demonstrate corresponding hyperperfusion and FLAIR hyperintensity. There is also ill-defined enhancement along the right splenium with mild hyperperfusion and FLAIR hyperintensity.There are bilateral extra-axial collections with the right collection appearing similar in size, measuring up to 9 mm. The left-sided collection appears nearly resolved with heterogeneous areas of increased susceptibility and diffusion restriction suggestive of residual blood products. Interval more focal blood products are also noted within the left paramedian anterior frontal and left posterior parietal subdural space measuring up to 6 mm in greatest thickness.There is redemonstration of an arachnoid cyst within the left middle cranial fossa measuring approximately 70 x 39 mm in AP and transverse dimensions (series 301, image 10). The cyst is still slightly T1 hyperintense with respect to CSF, but more homogeneously hyperintense on FLAIR. A definite fluid-blood level is no longer visualized. There is no associated diffusion restriction.There is no evidence of acute infarct. There is no midline shift or herniation. The major cerebral flow voids are intact.
1. Post-surgical findings of a right-sided craniotomy for prior resection of a right inferior parietotemporal lobe mass. There are multiple areas of stable scattered nodular enhancement along the margins of the resection cavity, with a few additional progressed or new nodular areas of enhancement extending from the margins some of which demonstrate hyperperfusion, including involvement of portions of the corpus callosum as well as scattered ependymal surfaces along the lateral ventricular margins. Findings are suspicious for tumor progression.2. Ill-defined nodular enhancement which appears progressed along the posterior aspect of the right thalamus, and does not demonstrate hyperperfusion.3. Previously described more heterogeneous prominence along the inferolateral aspect of the resection cavity appears decreased in prominence, likely evolved post-operative changes.4. Bilateral extra-axial collections appearing improved from prior exam. The right-sided collection is essentially stable, while the left-sided collection is nearly resolved except for a few areas of interval although non-acute more focal blood products, as detailed above.5. Interval expected evolution of blood products in left middle cranial fossa arachnoid cyst.