64层MDCT评价冠脉粥样硬化斑块的准确性:与IVUS对照研究

目的:评价64层MDCT在判断冠脉粥样硬化斑块性质及测量血管大小、斑块负担的应用价值。方法:14例患者经MDCT显示的位于冠脉近、中段的粥样硬化斑块作为研究对象,在斑块的最大层面测量斑块的CT值,根据CT值将斑块分类。并测量、计算最小管腔面积、血管外膜面积,斑块面积、斑块负荷。以IVUS为金标准,分别计算MDCT判断斑块性质的敏感性、特异性及各类斑块的平均CT值,并对血管测量进行统计学分析。结果:14例患者粥样硬化斑块25个,软斑块11个,纤维斑块7个,钙化斑块7个,平均CT值分别为49±32HU,93±23HU,1138±350HU。MDCT对脂质、纤维和钙化斑块诊断的敏感性和特异性分别为90.9%和92.9%;85.7%和94.4%;100%和100%。MDCT测量的管腔面积、血管面积、斑块面积、斑块负荷高于IVUS测量的结果,但两者之间没有统计学差异。结论:64层MDCT是一种准确无创的诊断和测量冠脉粥样硬化斑块的工具。

The accuracy of assessing coronary atherosclerotic plaque by 64-slice spiral CT: comparison with IVUS

Objective：To assess the value of 64-slice spiral CT in demonstrating coronary atherosclerotic plaque composition and quantification of plaque burden by comparison with intravascular ultrasound（IVUS）.Methods：Fourteen patients with atherosclerotic plaques on the proximal or middle segments of coronary artery demonstrated by MDCT were included.IVUS was performed after CT examination within a week.Coronary arteries were reconstructed using MIP and MPR and the cross-sectional images perpendicular to the long axis of coronary artery were obtained.The CT values of the plaques were measured.The plaques were classified as soft,fibrotic and calcified plaques according to CT values.The minimum lumen area（MLA）,external elastic membrane cross sectional area（EEM CSA） were measured and plaque area,plaque burden were calculated.The composition of plaques were confirmed by IVUS and the MLA,EEM CSA,plaque area,plaque burden measured or calculated by MDCT were compared with IVUS.The sensitivity and specificity of classifying plaques types by MDCT were assessed and average CT value of every type plaque was acquired.Results：Total 25 plaques were included in this study. The average CT value was 49±32 HU in 11 soft plaques,93±23 HU in 7 fibrotic plaques,1138±350 HU in 7 calcified plaques.The sensitivity and specificity of MDCT were 90.9% and 92.9% for identifying soft plaques,85.7% and 94.4% for fibrotic plaques,100% and 100% for calcified plaques.Vessel area,lumen area,plaque area and plaque burden measured or calculated by MDCT（16.2±5.1 mm2,6.58±4.1 mm2,9.61±3.8 mm2,60±18%） were higher than those by IVUS（14.5±4.8 mm2,6.28±4.3 mm2,8.22±3.6 mm2,58.5±20.1%）,but there was no statistical difference.Conclusion：64-slices MDCT is an accurate and noninvasive tool for assessment of coronary atherosclerotic plaque composition and quantification of plaque burden.