目的 研究联合应用18F-FDG PET CT和MRI在颈动脉粥样硬化斑块评价的 应用价值。方法 选取我院2016年2月至 2018年2月80例颈动脉粥样硬化斑块患者 为研究对象，均在2周内接受18F-FDG PET CT和MRI检查，在斑块周围勾画感兴趣区 (ROI)，获取标准化摄取值(SUV)，计算 靶-本底比值(TBR)；观察纤维帽完整性 及厚度，将斑块分为无纤维帽、厚纤维 帽、薄纤维帽、纤维帽碎裂；根据斑块 成分分组，包括胶原组、钙化组、脂质 组、出血组。结果 80例颈动脉粥样硬化 斑块患者，剔除图像质量不佳的7名患 者，累计扫描1930层，大部分斑块处于 颈动脉分叉处周围。根据纤维帽厚度分 组，无纤维帽1065层，厚纤维帽547层， 薄纤维帽202层，纤维帽破裂116层；根 据斑块成分分组，胶原236层，钙化796 层，脂质730层，出血168层。纤维帽破 裂组TBR显著高于其他三组(P＜0.05)， 薄纤维帽组TBR显著高于厚纤维帽组与无 纤维帽组(P＜0.05)，厚纤维帽组TBR显 著高于无纤维帽组(P＜0.05)。出血组 TBR显著高于脂质组、钙化组、胶原组(P ＜0.05)，脂质组TBR显著高于钙化组、 胶原组(P＜0.05)。结论 MRI可对纤维帽 及斑块成分进行定性评估，18F-FDG PET CT可反映斑块的炎症活动程度，二者联 合对颈动脉粥样硬化斑块的稳定性具有 重要提示作用。

Objective To study the value of 18F-FDG PET CT combined with MRI in the evaluation of carotid atherosclerotic plaque. Methods A total of eighty patients with carotid atherosclerotic plaques who were admitted to the hospital during the period from February 2016 to February 2018 were selected as study subjects. All patients were examined with 18F-FDG PET CT and MRI within 2 weeks. The region of interest (ROI) was drawn around the plaque to obtain the standardized uptake value (SUV), and the target-to-background ratio (TBR) was calculated. The integrity and thickness of fibrous cap were observed, and plaques were divide into non-fibrous cap, thick fibrous cap, thin fibrous cap and ruptured fibrous cap. They were grouped according to the composition of plaques, including collagen group, calcification group, lipid group and bleeding group. Results Of the 80 patients with carotid atherosclerotic plaques, 7 patients with poor image quality were excluded. A total of 1930 layers were scanned. Most of the plaques were located around the bifurcation of the carotid artery. There are 1065 layers without fibrous cap, 547 layers with thick fibrous caps, 202 layers with thin fibrous caps, and the other 116 layers with ruptured fibrous caps. Grouping according to the composition of plaques showed that there were 236 layers of collagen, 796 layers of calcification, 730 layers of lipidsand 168 layers of bleeding. The TBR in the fibrous cap rupture group was significantly higher than that in the other three groups (P<0.05). The TBR in the thin fibrous cap group was higher than the thick fibrous cap group, and higher than the nonfibrous cap group (P<0.05). The TBR in the bleeding group was significantly higher than that in the lipid group, calcification group or collagen group (P<0.05). The TBR in the lipid group was significantly higher than that in the calcification group or the collagen group (P<0.05). Conclusion MRI can evaluate the fibrous cap and composition of plaques qualitatively. 18F-FDG PET CT can reflect the degree of inflammatory activity of the plaque. The combined use of the two methods plays an important role in evaluating the stability of carotid atherosclerotic plaques.