Abstract TMP9: Flair Vascular Hyperintensities as Imaging Biomarker in Pediatric Arterial Ischemic Stroke

Abstract

Background: FLAIR vascular hyperintensities (FVH) are high signal intensities on MRI resulting from sluggish flow through collateral vessels in patients with acute arterial ischemic stroke (AIS). Data from adults suggest they may be a marker of penumbra. In this first investigation of FVH in children, I measured the prevalence and identified risk factors for FVH in pediatric patients with AIS. Methods: Retrospective review of patients prospectively enrolled in the CHOP Stroke Registry from 2006-2022. Patients with AIS age 29 days to 18 years with MRI within 72 hours of last known well were included. Children with pre-existing strokes, vasculopathy, prior brain surgery, radiation, or vascular compression from intracranial mass were excluded. MRIs were assessed by a blinded reviewer and adjudicated by a neuroradiologist for presence of LVO, FVH score, modASPECTS score, and AIS lesion volume. Clinical data were abstracted from chart review. Independent sample t-test compared FVH score and LVO presence. Pearson's correlation assessed the relationship between total FVH score and age, stroke size, modASPECTS, and pedNIHSS scores. Multivariable logistic regression evaluated predictors of significant FVH (score >= 3) and included time to MRI, large vessel occlusion, modASPECTS, pedNIHSS, stroke size, and age as independent variables. Results: 83 patients met inclusion criteria. Median time to MRI was 26 hours (95% CI 26-33). FVH were present in 45 patients (54%). Mean FVH score was higher in patients with LVO (5.22 ± 0.64) compared to those without (1.21 ± 0.24; p = 0.00). There was a positive correlation between total FVH score and age (p < 0.05), stroke size (p < 0.0001), modASPECTS (p < 0.0000), and pedNIHSS (p < 0.0002). In the multivariate logistic regression, only older age (OR 1.50, 95% CI 1.12-2.01, p < 0.006) and presence of LVO (OR 0.002, 95% CI 4.85x10 -5 -0.08, p<0.001) were associated with significantly increased odds of high FVH burden. Conclusions: FVH are prevalent in children with AIS, with higher burden in older children. Similar to adults, large vessel occlusion and larger infarct size are associated with higher FVH burden. Further study is needed on whether FVH could be used to identify patients who would benefit from reperfusion therapies.