Atherosclerotic aortic component quantification by noninvasive magnetic resonance imaging: an in vivo study in rabbits.

Abstract OBJECTIVES We sought to demonstrate the ability that noninvasive in vivo magnetic resonance imaging (MRI) has to quantify the different components within atherosclerotic plaque. BACKGROUND Atherosclerotic plaque composition plays a critical role in both lesion stability and subsequent thrombogenicity. Noninvasive MRI is a promising tool for the characterization of plaque composition. METHODS Thoracic and abdominal aortic atherosclerotic lesions were induced in rabbits (n = 5). Nine months later, MRI was performed in a 1.5T system. Fast spin-echo sequences (proton density-weighted and T2-weighted [T2W] images) were obtained (in-plane resolution: 350 × 350 microns, slice thickness: 3 mm). Magnetic resonance images were correlated with matched histopathological sections (n = 108). RESULTS A significant correlation (p 1 = 39.1, p = 0.016). CONCLUSIONS In vivo noninvasive high resolution MRI accurately quantifies fibrotic and lipidic components of atherosclerosis in this model. This may permit the serial analysis of therapeutic strategies on atherosclerotic plaque stabilization.