MAGIC DR - a handy mnemonic used to remember the potential causes of a cerebral ring enhancing lesion.
M - Metastasis
A - Abscess
G - Glioblastoma multiforme
I - Infarct (subacute phase)
C - Contusion
D - Demyelinating disease (eg. tumefactive MS)
R - Radiation necrosis
An alternative is DR MAGIC of course, which is what you may like to call yourself if you can remember the list! Although you can’t possibly know by looking at the single images, for what it is worth, the above cases are; A = metastasis, B = abscess, C = radiation necrosis, D = GBM, E = demyelination, F = contusion.