联合应用无创影像学技术预警颈动脉不稳定斑块的相关研究

目的应用高分辨率动态对比增强磁共振成像(DCE-MRI),正电子发射断层显像(PET)技术检测患者颈动脉粥样硬化斑块,比较不同斑块成分之间的炎性程度,为早期预警颈动脉粥样硬化提供临床依据。方法选取颈动脉超声下斑块厚度>2mm的患者41例,分别行DCE-MRI和PET检查。以DCE-MRI图像分析结果,依照粥样硬化斑块表面纤维帽(无纤维帽、厚纤维帽、薄纤维帽、纤维帽破裂)或斑块内血管成分(钙化、胶原、脂质、出血),分析不同斑块性质影像学区别。以DCE-MRI为向导标记PET斑块位置,计算局部放射性活度标准化靶-本底比值(TBR),将DCE-MRI及PET对比研究,比较不同成分斑块间炎性反应程度,以鉴别不稳定斑块。结果不同斑块表面纤维帽中:纤维帽破裂TBRmax值最高,无纤维帽TBRmax值最低,两者比较差异有统计学意义(P<0.01);不同斑块成分中TBRmax值由大到小排列为:斑块出血、富含脂质坏死核、斑块胶原、斑块钙化,除斑块胶原与斑块钙化比较无显著差异外,其他斑块血管成分间差异均有统计学意义(P<0.01)。结论 DCE-MRI和PET无创检查技术联合应用,可以用于颈动脉粥样硬化的早期诊断与评估。

Application of noninvasive imaging technics in detection of unstable carotid plaques

Objective To study the application of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)and positron emission tomography(PET)in detection of carotid atherosclerotic plaques,which could provide clinical basis for carotid atherosclerosis early warning by comparing inflammatooy reactions in different plaques.Methods Forty-one patients with their carotid intima-media thickness(IMT)>2mm who underwent DCE-MRI and PET were included in this study.The different findings of DCE-MRI and PET were analyzed,such as fiber caps on the surface of atherosclerotic plaques and vascular compositions in plaques.The location of plaques was marked by DCE-MRI and the standard target background ratio(TBR)was calculated.The inflammation reactions in different plaques were compared and the unstable plaques were identified.Results The TBR value was significantly higher in the patients with ruptured fiber caps than in those with intact fiber caps.The TBR value was the highest in bleeding plaque followed by in lipid plaque,collagen plaque,and calcified plaque.No significant difference was found in the TBR value among other plaues except for collagen plaque and calcified plaque.Conclusion DCE-MRI and PET can be used in early diagnosis of carotid atherosclerosis.