Figure 5. Graphical representation of the 3 scenarios of lesion development and evolution according to status of the blood-brain barrier, phase rim, lesion volume, and lesion T1 hypointensity.

(i) Evolution of a fully centrifugal lesion: no shift to centripetal enhancement pattern; no phase rim at any time point. (ii) Evolution of a centrifugal lesion to a centripetal lesion with transient phase rim: disappearance of the phase rim during the follow-up. (iii) Evolution of a centrifugal lesion to a centripetal lesion with persistent phase rim: persistence of the phase rim after enhancement resolution and reduced lesion volume shrinkage and reduced T1 intensity over time in comparison with the other lesion types. Years from lesion onset, the pathological correlate of the persistent phase rim can be assessed at autopsy. BBB, blood-brain barrier; DCE, dynamic contrast enhancement imaging.