Brain tumor. Status post resection. Evaluate extent of resection. The dural based, parasagittal right parietal mass has been near completely resected. There is small residual contrast enhancing tissue within the involved posterior segment of the superior sagittal sinus. There is also minimal, nodular contrast enhancing tissue is questioned in the adjacent dura over the right parietal convexity laterally and along the falx posteriorly. A small filling defect has developed in the superior sagittal sinus just anterior to the invaded segment and likely represents a small thrombus. Heterogeneous T1 shortening in the surgical bed reflects the blood products. Mild diffusion restriction along the resection cavity margin is consistent with cytotoxic edema with additional areas corresponding to blood products. The T2 hyperintensity surrounding the treatment surgical bed (vasogenic edema) has not significantly changed compared to the preoperative examination. The associated mass effect is stable or minimally improved with mild midline shift and mass effect on the right lateral ventricle but no uncal herniation.An extra-axial collection underlying the craniotomy flap has a maximum thickness of 11 mm (on sagittal images) causes mild mass effect on the underlying right perirolandic area. A small, thin right frontal subdural collection has a maximum thickness of 4 mm (on axial images) and causes no significant mass effect.The mastoid air cells and the paranasal sinuses are clear. The orbits are normal.
Expected postsurgical changes of right parietal parasagittal meningioma resection. There has been near total tumor resection with small residual enhancement within the invaded posterior superior sagittal sinus compatible with residual tumor. Minimal nodularity along the right parietal convexity dura and along the posterior falx may represent minimal residual tumor as well and can be assessed on follow-up studies.