EXPRESS: Diagnostic Accuracy of Noninvasive Translesional Pressure Ratio Based on Magnetic Resonance Imaging for Intracranial Atherosclerotic Stenosis: A Validation Study
Validation study demonstrates that vessel wall MRI accurately measures translesional pressure ratios in symptomatic ICAS, highlighting its potential as a noninvasive hemodynamic biomarker.
Key Points
To develop and validate a noninvasive, MRI-derived translesional pressure ratio framework to assess hemodynamic impairment in intracranial atherosclerotic stenosis.
Enrolled 42 patients with symptomatic intracranial atherosclerotic stenosis (mean stenosis, 75.3% ± 7.8%) who underwent invasive pressure-wire assessment.
Reconstructed vascular geometries for computational fluid dynamics using either time-of-flight MRA (TOF-PR) or high-resolution vessel wall imaging (VWI-PR), paired with phase-contrast MRA boundary conditions.
Evaluated correlation and agreement between MRI-derived pressure ratios and wire-based measurements using Pearson/Spearman analysis and Bland-Altman plots across stenosis severities.
VWI-PR demonstrated a strong correlation (r = 0.87, P < 0.001) and tight agreement (mean difference, 0.002 ± 0.09) with invasive wire-based pressure ratios across all stenosis grades.
TOF-PR exhibited a weaker correlation (r = 0.37, P = 0.016), poorer agreement (mean difference, -0.17 ± 0.25), and systematically underestimated translesional pressure ratios in severe stenosis.