Molecular Function and Imaging Program and the National Cardiac PET Centre, Division of Cardiology, Department of Medicine, University of Ottawa Heart Institute, Ottawa, Ontario, Canada.
Stroke Prevention & Atherosclerosis Research Centre, Robarts Research Institute, Western University, London, Ontario, Canada.
Int J Cardiol. 2018 Nov 15;271:378-386. doi: 10.1016/j.ijcard.2018.05.057. Epub 2018 Jun 2.
[18F]-fluorodeoxyglucose (FDG) uptake imaged with positron emission tomography (PET) and computed tomography (CT) may serve as a biomarker of plaque inflammation. This study evaluated the relationship between carotid plaque FDG uptake and a) intraplaque expression of macrophage and macrophage-like cellular CD68 immunohistology; b) intraplaque inflammatory burden using leukocyte-sensitive CD45 immunohistology; c) symptomatic patient presentation; d) time from last cerebrovascular event.
54 patients scheduled for carotid endarterectomy underwent FDG PET/CT imaging. Maximum 18FDG uptake (SUV) and tissue-to-blood ratio (TBR) was measured for carotid plaques. Quantitative immunohistological analysis of macrophage-like cell expression (CD68) and leukocyte content (CD45) was performed.
FDG uptake was related to CD68 macrophage expression (TBR: r = 0.51, p < 0.001), and total-plaque leukocyte CD45 expression (TBR: r = 0.632, p = 0.009, p < 0.001). FDG TBR uptake in carotid plaque associated with patient symptoms was greater than asymptomatic plaque (3.58 ± 1.01 vs. 3.13 ± 1.10, p = 0.008). FDG uptake differed between an acuity threshold of <90 days and >90 days (SUV:3.15 ± 0.87 vs. 2.52 ± 0.45, p = 0.015).
In this CAIN cohort, FDG uptake imaged with PET/CT serves a surrogate marker of intraplaque inflammatory macrophage, macrophage-like cell and leukocyte burden. 18FDG uptake is greater in plaque associated with patient symptoms and those with recent cerebrovascular events. Future studies are needed to relate FDG uptake and disease progression.
正电子发射断层扫描（PET）和计算机断层扫描（CT）显示的[18F]-氟脱氧葡萄糖（FDG）摄取可作为斑块炎症的生物标志物。本研究评估了颈动脉斑块 FDG 摄取与以下因素之间的关系：a）斑块内巨噬细胞和巨噬细胞样细胞 CD68 免疫组化的表达；b）使用白细胞敏感的 CD45 免疫组化的斑块内炎症负担；c）有症状的患者表现；d）距上次脑血管事件的时间。
54 例拟行颈动脉内膜切除术的患者接受了 FDG PET/CT 成像。测量颈动脉斑块的最大 18FDG 摄取（SUV）和组织与血液比值（TBR）。对巨噬细胞样细胞表达（CD68）和白细胞含量（CD45）进行定量免疫组织化学分析。
FDG 摄取与 CD68 巨噬细胞表达（TBR：r=0.51，p<0.001）和总斑块白细胞 CD45 表达（TBR：r=0.632，p=0.009，p<0.001）相关。颈动脉斑块中 FDG TBR 摄取与患者症状相关，大于无症状斑块（3.58±1.01 比 3.13±1.10，p=0.008）。FDG 摄取在<90 天和>90 天的时间阈值之间存在差异（SUV：3.15±0.87 比 2.52±0.45，p=0.015）。
在本 CAIN 队列中，PET/CT 成像的 FDG 摄取可作为斑块内炎症性巨噬细胞、巨噬细胞样细胞和白细胞负担的替代标志物。与无症状斑块和近期发生脑血管事件的斑块相比，斑块中的 FDG 摄取更高。需要进一步的研究来评估 FDG 摄取与疾病进展的关系。
