Thursday, May 17, 2012

Cerebral Ring Enhancing Lesions: Differential Diagnosis #15

Today's Daily Diff concerns cerebral ring enhancing lesions. The differential for this finding is fairly broad, and can have a significant impact on patient management. Having a brain metastasis is quite different from a resolving hematoma, no? To keep the various entities in mind, think of the phrase DR MAGIC. This is non-sensical, but if you see such a lesion, perhaps think of Magic Johnson having a Toxoplasma abscess, and um, he's a doctor now for some reason...

DiseaseNotes
DDemyelinating disease
RRadiation necrosisOften incomplete C-shaped ring
MMetastasesThick, nodular wall
AAbscessMarked restriction on DWI; thin wall
GGliomaThick, irregular wall if GBM
IInfarctBasal ganglia
CContusionResolving

Some people add L to the end of the mnemonic for lymphoma as well. Another entity to keep in mind, especially in certain patient populations, is neurocysticercosis, especially if there are other calcified lesions present.

Abscess
Source: Radiopaedia