Nonmodel-based Dynamic Contrast-enhanced Magnetic Resonance Imaging for the Assessment of High versus Low Risk Carotid Atherosclerosis

• Main Author: MacLean, David Bailey
• Other Authors: Mikulis, David J.
• Language: en_ca
• Published: 2011
• Subjects: Dynamic Contrast-Enhanced MRI; Stroke; Atherosclerosis; Carotid Artery; Nonmodel-Based; Semi-Quantitative; 0574; 0564
• Online Access: http://hdl.handle.net/1807/31326

Background: Parameters of carotid atherosclerosis dynamic contrast-enhanced MRI (DCE-MRI) are associated with stroke risk indices, but studies have only evaluated symptomatic arteries. I hypothesized that DCE-MRI parameters are different between carotid atherosclerotic plaques at high and low risk for precipitating ischemic stroke. Methods: High and low risk carotid plaques undergoing nonmodel-based DCE-MRI (n=18) were compared using two independent schema: 1) clinical standard (high risk defined as ipsilateral stroke/TIA <1 week old or stenosis >70%); 2) MRI standard (high risk defined as presence of intraplaque hemorrhage [IPH]). Results: IPH-positive plaques (n=9) exhibited greater area under the curve, early and late enhancement rate, and peak enhancement than IPH-negative plaques (n=9) (p<0.05 for all). High (n=8) and low (n=7) risk plaques defined by clinical criteria were not differentiated by any DCE-MRI parameters. Conclusions: Nonmodel-based DCE-MRI discriminates high versus low risk carotid plaque based on the presence of IPH, but not by clinical criteria.