7.0T MRI及Micro-PET无创检测小鼠动脉粥样硬化

Objective To explore the feasibility of detecting atherosclerosis with 7.0T MR and Micro-PET. Methods Ten 46-week-old ApoE-/-mice with high lipid diet for 6 months were selected to establish atherosclerosis models. Among them, 5 mice underwent MRI before and 12 h, 24 h, 36 h after injection of SPIO, respectively, and the other 5 mice were injected with 18F-fluorodeoxyglucose (18F-FDG) through tail vein and observed with Micro-PET after 1 h, 2 h and 3 h. The specimens of abdominal aorta were taken for pathologic examination. Results Atherosclerotic plaques were observed in all animals with 7.0T MRI after 6 months high lipid diet. Thirty-six hours after the injection of SPIO, the high signal rings were thinner and the lumen of blood vessels were wider than those before injection on T2WI. Radioactive concentration was observed in abdominal aorta and both sides of iliac artery 3 h after the injection of 18F-fluorodeoxyglucose (18F-FDG). Pathological examination showed the formation of atherosclerotic plaques and the aggregation of the macrophages. Conclusion 7.0T MRI and Micro-PET can be used to observe the macrophage-rich plaque and to judge the vulnerability of plaque, thus provide theoretical basis for early detection, diagnosis and treatment of atherosclerosis.