BRAIN ABSCESS - IMAGING FINDINGS

Key point: Contrast enhanced imaging demonstrates a well-defined, thin walled, enhancing rim.
CT phases:
Early cerebritis: Mild patchy enhancement.
Late cerebritis: Irregular rim-enhancement.
Early capsule: Low density center with thin, distinct enhancing rim.
Late capsule: Shrinking cavity and thickening capsule.
MR phases:
Early cerebritis: Ill-defined hypo/iso T1 and hyper T2 signal.
Late cerebritis: Hypo T1 center, iso/hyper T1 rim, hyper T2 center, hypo T2 rim, and surrounding hyper T2 edema.
Early capsule: Hyper T1 center, hyper T1 rim, hypo T2 rim.
Late capsule: Cavity shrinks, capsule thickens, and edema lessens.

source: auntminnie.com