Department of Interventional Cardiology, Cardiovascular Hospital and Claude Bernard University, INSERM Research Unit 886 and CREATIS Research Unit associated to CNRS (UMR 5515), B.P Lyon-Monchat, 69394, Lyon Cedex 03, France.
Int J Cardiovasc Imaging. 2010 Apr;26(4):373-83. doi: 10.1007/s10554-009-9562-y. Epub 2010 Jan 6.
The present study investigated whether IVUS could serve as a reliable reference in validating MDCT characterization of coronary plaque against a histological gold standard. Twenty-one specimens were postmortem human coronary arteries. Coronary cross-sections were imaged by 40 MHz IVUS and by 64-slice MDCT and characterized histologically as presenting calcified, fibrous or lipid-rich plaques. Plaque composition was analyzed visually and intra-plaque MDCT attenuation was measured in Hounsfield Units (HU). 83 atherosclerotic plaques were identified. IVUS failed to characterize calcified plaque accurately, with a positive predictive value (ppv) of 75% versus 100% for MDCT. Lipid-rich plaque was even less accurately characterized, with ppv of 60 and 68% for IVUS and MDCT respectively. Mean MDCT attenuation was 966 +/- 473 HU for calcified plaque, 83 +/- 35 HU for fibrous plaque and 70.92 HU +/- 41 HU for lipid-rich plaque. No significant difference in mean MDCT attenuation was found between fibrous and lipid-rich plaques (P = 0.276). In vivo validation of MDCT against an IVUS reference thus appears to be an unsuitable and unreliable approach: 40 MHz IVUS suffers from acoustic ambiguities in plaque characterization, and 64-slice MDCT fails to analyze plaque morphology and components accurately.
本研究旨在探讨 IVUS 是否可作为验证 MDCT 对冠状动脉斑块特征描述与组织学金标准一致性的可靠参考。21 个标本为人死后的冠状动脉。采用 40MHz 的 IVUS 和 64 层 MDCT 对冠状动脉横截面进行成像，并进行组织学特征描述，表现为钙化、纤维或富含脂质的斑块。通过目测对斑块成分进行分析，并以亨氏单位（HU）测量斑块内 MDCT 衰减。共识别出 83 个动脉粥样硬化斑块。IVUS 未能准确地对钙化斑块进行特征描述，其阳性预测值（PPV）为 75%，而 MDCT 为 100%。富含脂质的斑块特征描述更不准确，IVUS 和 MDCT 的 PPV 分别为 60%和 68%。钙化斑块的 MDCT 平均衰减值为 966±473HU，纤维斑块为 83±35HU，富含脂质的斑块为 70.92HU±41HU。纤维斑块和富含脂质斑块之间的 MDCT 平均衰减值无显著差异（P=0.276）。因此，MDCT 与 IVUS 参考值的体内验证似乎是一种不适当且不可靠的方法：40MHz 的 IVUS 在斑块特征描述方面存在声学模糊性，而 64 层 MDCT 无法准确分析斑块形态和成分。
