The Value Of ¹⁸F-FDG PET/CT In Evaluating The Stability Of Atherosclerotic Plaques

Objective:The sensitivity of PET/CT to in-vivo inflammation are adopted to evaluate the effect of atorvastatin on the stability of atherosclerotic plaques,and explore the possibility of evaluating the stability of atherosclerotic plaques and the efficacy of atorvastatin in stabilizing atherosclerotic plaques.Research methods:Twenty New Zealand male white rabbits were randomly divided into the atorvastatin intervention group?10 rabbits?and the control group?10 rabbits?by drawing lots.Both groups were fed a high-fat diet and atherosclerosis animal model was made 2 weeks later,and the high-fat diet was continued to the 20th week after surgery,in which the atorvastatin intervention group was given daily atorvastatin gavage.Hs-CRP and MMP-9 were tested twice at week 3 and 20,respectively.At week 20,the surviving animals underwent ¹⁸F-FDG PET/CT scans to measure SUV and SUVmax of the aorta segment.After that,experimental rabbits were sacrificed,and the aortic pathological specimens were made to measure the plaque area and the thickness of the plaque fibrous cap in the arterial segment.Macrophage density and apoptosis index were calculated by immunohistochemistry.Through statistical analysis,intra-group and inter-group comparison of each index was conducted,and correlation analysis was conducted.Results:1.At week 20,hs-CRP?4.58±0.51?and MMP-9?43.93±2.16?in the atorvastatin intervention group were significantly lower than those in the control group?5.87±0.66?and MMP-9?50.77±2.32?,with statistically significant differences.2.PET/CT images showed that both groups of experimental animals had irregular aortic wall and varying degrees of stenosis in the lumen in CTA.In PET images,local radioactive uptake of aorta was seen in both groups.Compared with the two groups,the control group showed obvious eccentric filling defect,and the stenosis of the lumen was more serious,theradioactive uptake was more significant.3.At week 20,SUVmean?0.59±0.15?and SUVmax?0.68±0.20?in the atorvastatin intervention were significantly lower than those in the control group?0.68±0.20?and SUVmax?0.81±0.27?,with statistically significant differences.4.At week 20,the plaque fibrous cap thickness?0.36±0.24?in the atorvastatin intervention group was significantly greater than that in the control group?2.96±0.37?,and the difference was statistically significant.5.At week 20,plaque area?0.36±0.24?,macrophage density?4.34±1.54?and apoptosis index?0.21±0.13?of the atorvastatin intervention group were significantly lower than those of the control group,with statistically significant differences.6.The area of corresponding arterial plaque was positively correlated with SUVmean?r=0.27,P<0.05?and SUVmax?r=0.43,P<0.01?.7.Fiber cap thickness of the plaque was negatively correlated with SUVmean?r=-0.38,P<0.05?and SUVmax?r=-0.47,P<0.01?.8.The density of macrophages in plaques was positively correlated with SUVmean?r=0.52,P<0.01?and SUVmax?r=0.51,P<0.01?.9.Apoptosis index in plaque was positively correlated with SUVmean?r=0.46,P<0.01?and SUVmax?r=0.39,P<0.01?.Conclusion:.1.¹⁸F-FDG PET/CT can be used to evaluate the stability of atherosclerotic plaques.2.Through ¹⁸F-FDG PET/CT,it can be observed that atorvastatin can reduce the area of atherosclerotic plaques and stabilize vulnerable plaques.¹⁸F-FDG PET/CT can evaluate the effect of atorvastatin on the stability of atherosclerotic plaques and the efficacy of atorvastatin.3.Atorvastatin has anti-apoptotic effect.