MRI
There are least four focal regions of signal abnormality. The largest region of signal abnormality involves the bilateral anterior frontal lobes in a near symmetric pattern. The cortex appears essentially spared with enhancement centred on the juxtacortical and subcortical white matter. Multiple punctate regions of haemorrhage are seen embedded within the frontal lobe abnormality. CBV is not elevated. MRS demonstrates elevation of choline and lactate (not shown).
The other abnormal regions of T2 FLAIR hyperintensity and enhancement are very similar in imaging characteristics and also appear to involve the juxtacortical white matter including the left anterior temporal lobe, right mesial temporal lobe and right parietal lobe/postcentral gyrus. These regions are not clearly connected by T2 FLAIR signal change. No extra-axial abnormality. Ventricles and basal cisterns are normal in appearance.
Conclusion:
Overall, in the absence of significant prior illness/immunosuppression/ immune reconstitution, findings are most compatible with an acute monophasic demyelinating disease - acute disseminated encephalomyelitis (ADEM) or (given the haemorrhages) acute haemorrhagic leukoencephalitis.
Given CBV and ADC features, mulitcentric glioma or lymphoma are thought much less likely.