What is the finding on contrast enhanced CT?
Multiple ring enhancing regions in the right frontal and temporal lobes.
What is the differential diagnosis for this appearance?
The wide differential diagnosis for cerebral ring enhancing lesions is summarised by the mnemonic MAGIC DR: Metastasis, Abscess, Glioma, Infarct, Contusion, Demyelination, Radiation necrosis.
Which do you favour in this patient?
The main considerations in this setting are cerebral abscesses (febrile patient, recent intervention with burhole), and subacute contusions.
Followup study performed some time after admission. Contrast was given due to clinical concern of possible ventriculitis.
The non contrast CT decreased volume and density of the multifocal haemorrhages, in keeping with expected temporal evolution. There are several regions of parenchymal hypoattenuation in the right frontal lobe, deep to the site of a bur hole.
Post contrast, these regions demonstrate thin rim enhancement with mild surrounding vasogenic oedema.