Three-dimensional Rotational Angiography Assessment of Symptomatic Intracranial Atherosclerotic Disease Plaque Evolution under Medical Treatment

Background Understanding how symptomatic intracranial atherosclerotic disease (sICAD) evolves and identifying high-risk lesion characteristics could improve risk stratification. Purpose To delineate the evolution patterns of plaque morphologic features and focal hemodynamics in sICAD and identify morphologic features and hemodynamics associated with plaque progression and recurrence of stroke and/or transient ischemic attack (TIA). Materials and Methods In this prospective, longitudinal study, participants with high-grade (60%-99% stenosis) sICAD confirmed at three-dimensional rotational angiography (3DRA) between August 2007 and December 2021 received guideline-based medical treatment, with follow-up evaluations at 1, 3, 6, and 12 months and every 6 months afterward. All participants underwent follow-up 3DRA at 1 year or upon stroke recurrence if earlier. The sICAD plaque morphologic features and focal hemodynamics were assessed and compared at baseline and follow-up 3DRA and using 3DRA-based computational fluid dynamics models. The primary outcome was a composite of relevant ischemic stroke or hard TIA recurrence and/or plaque progression in 3DRA at 1 year. Results Among 97 participants (median age, 62 years IQR, 56-68 years; 68 male), the primary outcome occurred in 26 (27%): 17 (18%) with relevant ischemic stroke and/or TIA recurrence and nine (9%) with plaque progression. Focal pressure and wall shear stress measures also changed over 1 year. Greater plaque thickness (adjusted odds ratio, 10.49 95% CI: 2.67, 41.20), smaller upstream plaque shoulder angulation (adjusted odds ratio, 0.97 95% CI: 0.95, 1.00), and maximum stenosis located distally (adjusted odds ratio, 3.81 95% CI: 1.19, 12.18) at baseline were independently associated with primary outcome. Higher and lower wall shear stress measures across the upstream and downstream plaque segments, respectively, at baseline were also associated with primary outcome. Conclusion Plaque morphologic features and focal hemodynamics evolved over time in participants with sICAD under medical treatment; thicker plaque, smaller upstream shoulder angulation, and skewed distal load were associated with lesion progression and recurrence of stroke and/or TIA. © The Author(s) 2026. Published by the Radiological Society of North America under a CC BY 4.0 license.