Characterization of WMH penumbra and lesion progression using baseline and longitudinal WMH layer analysis with FLAIR and PCASL

Motivation: Characterization of the structural and functional changes along WMH lesion and penumbra could provide pivotal information about the mechanism of WMH development and progression. Goal(s): To characterize WMH penumbra and WMH lesion progression using baseline and longitudinal WMH layer analysis using FLAIR and PCASL MRI Approach: MRI FLAIR and PCASL were analyzed between baseline and follow-up acquisitions. Results: FLAIR showed significance in all tested layers (p=0.0001 to 0.0005). CBF with PVC improved sensitivity to WMH progression in layers 4 and 5 (p=0.0055,0.0066). New WMH instances occurred predominantly by expansion from the baseline (94.92±5.80 % of new WMH) Impact: Both FLAIR and pCASL CBF reveal the WMH progression. New WMH formation was shown to occur primarily by expansion from existing WMH. The WMH layer characterization may help elucidate the mechanics of the WMH progression.