Multiple intracranial masses with pronounced surrounding vasogenic oedema are again identified. The masses themselves are isointense or mildly hyperintense to cortex on FLAIR and T2-weighted imaging, in contrast to the surrounding markedly T2 hyperintense vasogenic oedema.
The more rounded lesions include: Left lentiform nucleus. Left infralateral thalamus. Left superomedial thalamus. Left posteromedial temporal lobe. Right corona radiata . Right posterior frontal subcortical. Left superior frontal gyrus contains at least two small cortical lesions with subjacent vasogenic oedema.
On the CT performed yesterday these rounded lesions were centrally iso to hypodense with peripheral enhancement. The left thalamic lesion demonstrates internal marked ADC reduction of non-enhancing content which raises the possibility of abscess. Linear diffusion restriction related the right corona radiata and right posterior frontal cortical abnormality appears to correspond to locations demonstrating enhancement on CT.
In addition, there is cortical expansion with pronounced subjacent vasogenic oedema throughout the right occipital lobe, where thick leptomeningeal enhancement was documented on recent CT. A region of right frontal vasogenic oedema and cortical signal abnormality was also associated with leptomeningeal rather than rounded focal enhancement on recent CT. There is no midline shift or uncal herniation. No tonsillar herniation. No hydrocephalus.
Multiple intraparenchymal masses and areas of leptomeningeal abnormality with associated vasogenic oedema, corresponding to the areas of thin walled peripherally enhancing masses in leptomeningeal enhancement on recent CT. In the context of immunosuppression, atypical infection (including toxoplasmosis and fungus) is favoured over metastasis. The left thalamic lesion and to a lesser extent left lentiform nucleus lesion demonstrates internal ADC reduction corresponding to non-enhancing content, which raises suspicion for cerebral abscess.