Intra-axial, cortically based lesion at the left frontal lobe demonstrates heterogeneous hypointensity on T1 and hyperintensity on T2-weighted sequences with a small central area of signal suppression on FLAIR sequences. Internal susceptibility artefact corresponds with curvilinear calcification seen on previous CT. MR spectroscopy demonstrates a reversed choline:creatinine ratio decreased NAA and increased myoinositol. Several vessels traverse the lesion, and this is also seen on perfusion sequences, although there is no contrast enhancement otherwise.
Orbital roof fractures are better seen on previous CT, associated with periorbital oedema.
Conclusion:
Left frontal lobe mass is favoured to represent oligodendroglioma given its size, presence of calcification and traversing vessels, and central cystic changes. Other differentials include dysembryoplastic neuroepithelial tumour or low-grade astrocytoma.