Characteristics of Atherosclerotic Plaques and Stroke Mechanism in Patients with Border-Zone Infarcts: A High-resolution Magnetic Resonance Imaging Study

Abstract

BackgroundRelatively little is known about the plaque characteristics of border-zone infarcts and how they differ between cortical border-zone (CBZ) and internal border-zone (IBZ) infarcts. MethodsWe conducted a prospective observational cohort study of patients of intracranial atherosclerotic disease who underwent high-resolution magnetic resonance imaging (HR-MRI) examination. Individuals with border-zone infarcts in the middle cerebral artery (MCA) territory, detected by diffusion-weighted imaging, were enrolled. Plaque morphological and compositional parameters of both IBZ and CBZ groups were compared. Independent predictors were identified using a binary logistic regression model, and the sensitivity and specificity of the model were assessed using a receiver operating characteristic curve. Kaplan-Meier survival analysis further explored differences in stroke recurrence between BZ patients with mono or dual antiplatelet therapy. ResultsWe reviewed 101 symptomatic patients with border-zone infarcts (BZ) within the MCA territory in the study. Out of the patients meeting the imaging eligibility criteria, we detected 34 cases with isolated IBZ, 23 cases with isolated CBZ, and 6 cases with both IBZ and CBZ infarcts. Those with IBZ infarcts had a higher plaque burden than those without (p<0.001), and those with CBZ infarcts exhibited a complicated plaque less frequently than those without (37.9% vs 67.6%, p=0.018). In those with isolated IBZ or CBZ infarcts, plaque burden was independently associated with isolated IBZ infarcts (odd ratio=1.08; 95% CI, 1.02-1.15; p=0.023). During the median follow-up period of 37 (27, 50) months, 13.8% of patients receiving early dual antiplatelet treatment and 30.4% of those on single antiplatelet therapy experienced stroke recurrence (p=0.182). ConclusionsIntracranial atherosclerotic plaque morphology and composition differ between patients with IBZ and those with CBZ infarcts. Higher plaque burden is more associated with IBZ infarcts.