Regional Cerebral Blood Flow Patterns on ASL in Subacute Sclerosing Panencephalitis: Quantitative Analysis and...

Area of Science:

• Neuroimaging
• Neuroinflammation
• Radiology

Background:

• Subacute sclerosing panencephalitis (SSPE) is a fatal neuroinflammatory disease.
• Conventional MRI shows structural damage but misses early hemodynamic changes.
• Measles virus persistence causes chronic inflammation and network dysfunction in SSPE.

Purpose of the Study:

• To characterize regional perfusion patterns in SSPE using arterial spin labeling (ASL).
• To define qualitative perfusion phenotypes in SSPE.
• To examine the association of perfusion patterns with clinical severity and disease stage.

Main Methods:

• Retrospective case-control study of 33 SSPE patients and 8 controls using 3T MRI with ASL.
• Cerebellar-normalized perfusion ratios (CNRs) computed across 8 regions.
• Correlations assessed with Neurological Disability Index (NDI), Barthel Index, and illness duration.

Main Results:

• Significantly elevated CNRs in SSPE patients compared to controls in 6/8 regions.
• Basal ganglia hyperperfusion was the dominant ASL pattern, showing a dissociation from structural MRI findings.
• Deep grey matter CNRs correlated with neurological severity (NDI) but not illness duration.

Conclusions:

• ASL-derived CNRs indicate regionally specific hyperperfusion in SSPE, reflecting active neuroinflammation.
• ASL may detect hemodynamic alterations before structural injury is evident on MRI.
• ASL may track disease activity intensity rather than chronological extent in SSPE.