What is your differential?
Overall, these findings are compatible with a neoplastic process, most likely a high grade glioma (e.g. GBM). Proximity of the epicentre to the ventricle and presence of peripheral haemorrhage (hemosiderin capping) does raise the possibility of an ependymoma. Other possibilities include a bizarre cavernous malformation or metastasis.
What can be seen in the left anterior most cystic component (T2)?
A fluid fluid level with the dependent portion demonstrating signal drop out in keeping with blood products.
There is a large left frontal mixed cystic/solid lesion, measuring approximately 4x4x5cm in perpendicular dimensions, with intralesional haemorrhage and fluid level which may indicate areas of necrosis. Large surrounding vasogenic edema involving the contralateral hemisphere, and significant mass effect causing almost 2cm midline shift, obstructing the monro foramina resulting moderate non-communicating hydrocephalus.
The epicenter of the mass demonstrates diffusion restriction. There is no evidence of an increased rCBV. MRS demonstrates significantly increased choline and lactate/lipid peak with substantial decrease in NAA (not shown).