Quantification and 3D reconstruction of atherosclerotic plaque components in apolipoprotein E knockout mice using ex vivo high-resolution MRI.

Journal article

OBJECTIVE: To investigate the ability of high-resolution MRI to determine composition and microanatomy of atherosclerosis in mouse aortic root and brachiocephalic artery. METHODS AND RESULTS: Aortic root and brachiocephalic arteries of apolipoprotein E knockout (apoE-/-) mice fed Western diet for 10, 20, or 30 weeks were imaged ex vivo (11.7 T; 3D multiecho sequence; resolution 47x47x62.5 microm). Using semiautomated histogram-based methods, MRI accurately quantified lipid-rich/necrotic areas in the aortic root (r2=0.84; P<0.001) and brachiocephalic artery (r2=0.90; P<0.001) compared with histology. Similarly, cell-rich caps in aortic roots, quantified by MRI and histology, correlated closely (r2=0.74; P<0.001). Reconstruction of segmented brachiocephalic arteries in 3D provided unique insights into plaque microanatomy and enabled volumetric quantification of plaque and lipid-rich/necrotic core. Between 10 and 30 weeks, 3D measurement identified an 11.6-fold increase in plaque volume (versus 4.1-fold for 2D) and a 21.3-fold increase in plaque lipid-rich/necrotic core volume (versus 6.4-fold for 2D), indicating superior power of 3D quantification. CONCLUSIONS: Ex-vivo high-resolution 3D MRI accurately quantified lipid-rich/necrotic core and cell-rich cap areas in atherosclerotic lesions in apoE-/- mice. Reconstruction and volumetric quantification of segmented brachiocephalic arteries demonstrated greater sensitivity in detecting changes in plaque size and lipid composition over time than 2D analysis.

Authors: McAteer, M; Schneider, J; Clarke, K; Neubauer, S; Channon, K

• Publication status: Published
• Journal: Arteriosclerosis, thrombosis, and vascular biology
• Volume: 24
• Issue: 12
• Pages: 2384-2390
• Publication date: 2004-12-01
• DOI: 10.1161/01.atv.0000146811.19029.fb
• EISSN: 1524-4636
• ISSN: 1079-5642
• Language: English
• Keywords: Lipid Metabolism; Animals; Apolipoproteins E; Mice, Inbred C57BL; Magnetic Resonance Imaging; Brachiocephalic Trunk; Aorta; Necrosis; Mice, Knockout; Imaging, Three-Dimensional; Arteriosclerosis; Reproducibility of Results; Mice