Abstract
Objective: Contrast enhancement is a vital feature of the intracranial atherosclerotic plaque on high-resolution magnetic resonance imaging (HRMRI), but its clinical significance is still unclear. We aimed to quantitatively assess plaque enhancement patterns in the middle cerebral artery (MCA) atherosclerotic plaque.Methods: We conducted a cross-sectional study by prospectively recruiting stroke or transient ischemic attack patients with >30% of MCA stenosis of either side. All patients underwent contrast-enhanced HRMRI scans. Enrolled patients were classified into acute phase (<4 weeks), subacute phase (4–12 weeks) and chronic phase (>12 weeks) groups based on the time interval from stroke onset to imaging scan. Plaque enhancement index was calculated for each MCA lesion at the maximal narrowing site.Results: We identified a total of 89 MCA plaques [53 (60%) symptomatic and 36 (40%) asymptomatic; 57 (64%) acute, 18 (20%) subacute and 14 (16%) chronic] in 58 patients on HRMRI. Among the acute lesions, symptomatic plaques had a significantly stronger plaque enhancement than asymptomatic plaques (symptomatic vs. asymptomatic: 38.9 ± 18.2 vs. 18.2 ± 16.2, p < 0.001). Among the symptomatic lesions, plaque enhancement diminished with increasing time after stroke onset (38.9 ± 18.2, 22.0 ± 22.8, and 5.0 ± 10.1 for acute, subacute, and chronic phase, respectively; p = 0.001).Conclusion: Plaque enhancement in the acute atherosclerotic plaque is closely related to recent ischemic events. In symptomatic atherosclerosis, plaque enhancement regresses over time after ischemic stroke, which may offer the potential to monitor the plaque activity in intracranial atherosclerosis using HRMRI.
Highlights
Intracranial atherosclerotic disease (ICAD) is a leading cause of ischemic stroke, especially among Asian stroke patients [1, 2]
In addition to lumen stenosis that has long been used as an imaging standard for risk-stratifying patients, pathological studies reveal that some other plaque features, such as large lipid core, increased neovascularization, and plaque inflammation, contribute to plaque instability and thromboembolic events [3, 4], highlighting the importance of visualizing the plaque components to predict future vascular events
We aimed to investigate whether the strength of plaque enhancement in middle cerebral artery (MCA) atherosclerosis changes after the onset of ischemic stroke
Summary
Intracranial atherosclerotic disease (ICAD) is a leading cause of ischemic stroke, especially among Asian stroke patients [1, 2]. The challenge for current imaging modalities is to detect the presence of intracranial atherosclerotic plaque and to clarify the high-risk lesions that are vulnerable to thrombosis. Several clinical studies have been done to validate the utility of HRMRI in characterizing imaging features of high-risk intracranial atherosclerotic lesions, including plaque distribution, intraplaque hemorrhage (IPH), patterns of arterial remodeling [7,8,9,10,11]. A few studies demonstrated that the strength of contrast enhancement in symptomatic plaques decreased with increasing time after ischemic stroke [22, 23], but the sample size is relatively small to draw a firm conclusion. We aimed to investigate whether the strength of plaque enhancement in middle cerebral artery (MCA) atherosclerosis changes after the onset of ischemic stroke
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
