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Introduction: Vascular remodeling is a compensatory enlargement of the vessel wall in response to atherosclerotic plaque growth. We aimed to investigate the association between intraplaque hemorrhage (IPH), vascular remodeling, and luminal dimensions in recently symptomatic patients with mild to moderate carotid artery stenosis in which the differences in plaque size were taken into account. Materials and Methods: We assessed vessel dimensions on MRI of the symptomatic carotid artery in 164 patients from the Plaque At RISK study. This study included patients with recent ischemic neurological event and ipsilateral carotid artery stenosis <70%. The cross section with the largest wall area (WA) in the internal carotid artery (ICA) was selected for analysis. On this cross section, the following parameters were determined: WA, total vessel area (TVA), and lumen area (LA). Vascular remodeling was quantified as the remodeling ratio (RR) and was calculated as TVA at this position divided by the TVA in an unaffected distal portion of the ipsilateral ICA. Adjustment for WA was performed to correct for plaque size. Results: Plaques with IPH had a larger WA (0.56 vs. 0.46 cm2; p < 0.001), a smaller LA (0.17 vs. 0.22 cm2; p = 0.03), and a higher RR (2.0 vs. 1.9; p = 0.03) than plaques without IPH. After adjustment for WA, plaques containing IPH had a smaller LA (B = −0.052, p = 0.01) than plaques without IPH, but the RR was not different. Conclusion: After correcting for plaque size, plaques containing IPH had a smaller LA than plaques without IPH. However, RR was not different. [ABSTRACT FROM AUTHOR]

Background: Patients with a recent ischemic stroke have a higher risk of recurrent stroke compared to (ocular) transient ischemic attack (TIA) patients. Plaque microvasculature is considered as a feature of plaque vulnerability and can be quantified with carotid dynamic contrast-enhanced MRI (DCE-MRI). The purpose of this cross-sectional study was to explore the association between plaque microvasculature and the type of recent cerebrovascular events in symptomatic patients with mild-to-moderate carotid stenosis. Methods: A total of 87 symptomatic patients with a recent stroke (n = 35) or (ocular) TIA (n = 52) underwent carotid DCE-MRI examination. Plaque microvasculature was studied in the vessel wall and adventitia using DCEMRI and the pharmacokinetic modeling parameter Ktrans. Statistical analysis was performed with logistic regression, correcting for associated clinical risk factors. Results: The 75th percentile adventitial (OR 1.97, 95% CI 1.18-3.29) Ktrans was significantly associated with a recent ischemic stroke compared to (ocular) TIA in multivariate analysis, while clinical risk factors were not significantly associated with the type of event. Conclusions: This study indicates a positive association of leaky plaque microvasculature with a recent ischemic stroke compared to (ocular) TIA. Prospective longitudinal studies are needed to investigate whether Ktrans or other plaque characteristics may serve as an imaging marker for predicting (the type of) future cerebrovascular events. [ABSTRACT FROM AUTHOR]

Background: In addition to stenosis grading, magnetic resonance imaging (MRI) may provide valuable information about plaque ‘status’, e.g. hyperintense vulnerable carotid plaque, associated with higher morbidity and mortality. In the present study, we investigated the prevalence, clinical and radiological correlates of hyperintense carotid plaques on T1-weighted turbo-field echo (T1w-TFE) MRI in patients with ischemic symptoms. Methods: A total of 153 patients presenting with transient ischemic attack or ischemic infarct, studied with contrast-enhanced magnetic resonance angiography (CEMRA), were retrospectively examined. Stenosis grade was obtained from CEMRA images, presence or absence of hyperintense carotid plaque from T1w-TFE MRI. Stenosis grade and baseline characteristics were compared between patients with and without a hyperintense plaque. Results: Twenty-eight patients (18%) showed one or more hyperintense internal carotid (ICA) plaques. Hyperintense plaques were found in patients with <50% stenosis (6 of 158 ICAs), 50–70% stenosis (4 of 11), >70% stenosis (14 of 74) and carotid occlusion (4 of 28). Presence of hyperintense plaque was associated with older age (70 vs. 62 years; p < 0.05), higher prevalence of cardiac disease (61 vs. 28%; p < 0.01), ischemic infarct as presenting symptom (37 vs. 14%; p < 0.01), ischemic cerebral lesions on MRI (63 vs. 32%; p < 0.01), and the ICA on the patients’ symptomatic side (70 vs. 42%; p < 0.01). Conclusions: More than one third of patients with 50–70% stenosis present with a hyperintense plaque. This subgroup of patients could in the future possibly benefit from more aggressive medicinal therapy or revascularization. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]