There is a large extra-axial right occipitoparietal convexity T1 and T2 isointense solidly enhancing tumour. There is trans osseous invasion of the overlying right paramedian parietal bone with extracranial subgaleal tumour extension. There is a focal area of flair hyperintensity in the parietal white matter anterior and inferior to the lesion. The lesion is very close to the right lateral wall of the posterior third of the superior sagittal sinus with focal invasion of the right side of the sinus; the sinus is narrowed but not definitely occluded. MR venogram was not performed on this occasion. Within the central aspect of the lesion there are punctate areas of susceptibility corresponding to the calcification noted on the CT scan.
There is no other intracranial mass lesions. There is no signal alteration in the brain parenchyma.
IMPRESSION:
There is extra-axial right parieto-occipital convexity solidly enhancing tumour with transosseous invasion; the imaging appearances are most probably of a meningioma. Haemangiopericytoma can also be considered but the presence of calcification is atypical, and generally haemangiopericyytomas destroy bone rather than 'pass through it'.