Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, 8091 Zurich, Switzerland.
Int J Cardiovasc Imaging. 2013 Jun;29(5):1129-35. doi: 10.1007/s10554-012-0173-7. Epub 2013 Jan 18.
To systematically investigate into the relationships between luminal enhancement, convolution kernel, plaque density, and stenosis severity in coronary computed tomography (CT) angiography. A coronary phantom including 63 stenoses (stenosis severity, 10-90%; plaque densities, -100 to 1,000 HU) was loaded with increasing solutions of contrast material (luminal enhancement, 0-700 HU) and scanned in an anthropomorphic chest. CT data was acquired with prospective triggering using 64-section dual-source CT; reconstructions were performed with soft-tissue (B26f) and sharp convolution kernels (B46f). Two blinded and independent readers quantitatively assessed luminal diameter and CT number of plaque using electronic calipers. Measurement bias between phantom dimensions and CT measurements were calculated. Multivariate linear regression models identified predictors of bias. Inter- and intra-reader agreements of luminal diameter and CT number measurements were excellent (ICCs > 0.91, p < 0.01, each). Measurement bias of luminal diameter and plaque density was significantly (p < 0.01, each) lower (-12% and 58 HU, respectively) with B46f as opposed to B26f, especially in plaque densities >200 HU. Measurement bias was significantly (p < 0.01, each) correlated (ρ = 0.37-55 and ρ = -0.70-85) with the differences between luminal enhancement and plaque density. In multivariate models, bias of luminal diameter assessment with CT was correlated with plaque density (β = 0.09, p < 0.05). Convolution kernel (β = -0.29 and -0.38), stenosis severity (β = -0.45 and -0.38), and luminal enhancement (β = -0.11 and -0.29) represented independent (p < 0.05,each) predictors of measurement bias of luminal diameter and plaque number, respectively. Significant independent relationships exist between luminal enhancement, convolution kernel, plaque density, and luminal diameter, which have to be taken into account when performing, evaluating, and interpreting coronary CT angiography.
为了系统地研究冠状动脉计算机断层扫描（CT）血管造影中管腔增强、卷积核、斑块密度和狭窄严重程度之间的关系。一个冠状动脉体模包含 63 个狭窄（狭窄严重程度 10-90%；斑块密度-100 到 1000 HU），用不同浓度的造影剂溶液（管腔增强 0-700 HU）进行加载，并在拟人胸部进行扫描。使用 64 层双源 CT 进行前瞻性触发采集 CT 数据；使用软组织（B26f）和锐化卷积核（B46f）进行重建。两名盲法和独立的读者使用电子卡尺定量评估斑块的管腔直径和 CT 数。计算体模尺寸与 CT 测量值之间的测量偏差。多元线性回归模型确定了偏差的预测因素。管腔直径和 CT 数测量的读者间和读者内一致性均非常好（ICC > 0.91，p < 0.01，均）。使用 B46f 与 B26f 相比，管腔直径和斑块密度的测量偏差（p < 0.01，均）显著降低（分别为-12%和 58 HU），尤其是在斑块密度>200 HU 时。测量偏差与管腔增强和斑块密度之间的差异显著相关（ρ = 0.37-55 和 ρ = -0.70-85）（p < 0.01，均）。多元模型中，CT 评估的管腔直径的偏差与斑块密度相关（β = 0.09，p < 0.05）。卷积核（β = -0.29 和 -0.38）、狭窄严重程度（β = -0.45 和 -0.38）和管腔增强（β = -0.11 和 -0.29）分别是管腔直径和斑块数量测量偏差的独立预测因素（p < 0.05，均）。管腔增强、卷积核、斑块密度和管腔直径之间存在显著的独立关系，在进行、评估和解释冠状动脉 CT 血管造影时必须考虑这些关系。
