Measuring coronary calcium on CT images adjusted for attenuation differences
Measuring coronary calcium on CT images adjusted for attenuation differences
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DOI：
10.1148/radiol.2352040515
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发表时间：
2005-05-01
期刊：
影响因子：
19.7
通讯作者：
Detrano, R
中科院分区：
文献类型：
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作者：
Nelson, JC;Kronmal, RA;Detrano, R
目得：为了量化扫描仪和参与者的衰减值的变异性计算机断层扫描（CT）图像评估冠状动脉钙和定义一种方法标准化衰减值和校准calibratingcalciummeasurement.MATERIALS和METHODS：机构审查委员会的批准和参与者知情同意书，在所有的研究地点。开发了一种图像衰减调整方法，该方法涉及使用可用的校准体模数据来定义标准衰减值。该方法应用于两项基于人群的多中心研究的图像：年轻人冠状动脉风险发展研究（3041名参与者）和动脉粥样硬化多种族研究（6814名参与者）。为了量化衰减的变异性，使用方差分析技术来比较研究中心之间标准化躯干体模区域的CT数，并开发了参与者特定校准体模衰减值的多元线性回归模型，其中包括参与者年龄、种族、性别、体重指数（BMI）、吸烟状态和研究中心作为协变量。为了评估校准方法对钙测量值的影响，计算了未校正和衰减校正钙测量值之间的Pearson相关系数。多变量模型被用来检查性别，种族，体重指数，吸烟状况，未调整的分数，和网站上的Agatston评分adjustment.RESULTS的效果：平均衰减值（CT数字）的标准校准体模下扫描参与者根据扫描仪和参与者的体重指数显着变化（P <0.001）。Siemens多探测器行CT扫描仪的值最低（110.0 HU），其次是GE-Imatron电子束（116.0 HU）和GE LightSpeed多探测器行扫描仪（121.5 HU）。病态肥胖（BMI，>= 40.0 kg/m2）参与者的数值也较低（108.9 HU），其次是肥胖（BMI，30.0-39.9 kg/m2）（114.8 HU），超重（BMI，25.0-29.9 kg/m2）（118.5 HU）和正常体重或体重不足（BMI，
PURPOSE: To quantify scanner and participant variability in attenuation values for computed tomographic (CT) images assessed for coronary calcium and define a method for standardizing attenuation values and calibrating calcium measurements.MATERIALS AND METHODS: Institutional review board approval and participant informed consent were obtained at all study sites. An image attenuation adjustment method involving the use of available calibration phantom data to define standard attenuation values was developed. The method was applied to images from two population-based multicenter studies: the Coronary Artery Risk Development in Young Adults study (3041 participants) and the Multi-Ethnic Study of Atherosclerosis (6814 participants). To quantify the variability in attenuation, analysis of variance techniques were used to compare the CT numbers of standardized torso phantom regions across study sites, and multivariate linear regression models of participant-specific calibration phantom attenuation values that included participant age, race, sex, body mass index (BMI), smoking status, and site as covariates were developed. To assess the effect of the calibration method on calcium measurements, Pearson correlation coefficients between unadjusted and attenuation-adjusted calcium measurements were computed. Multivariate models were used to examine the effect of sex, race, BMI, smoking status, unadjusted score, and site on Agatston score adjustments.RESULTS: Mean attenuation values (CT numbers) of a standard calibration phantom scanned beneath participants varied significantly according to scanner and participant BMI (P < .001 for both). Values were lowest for Siemens multi-detector row CT scanners (110.0 HU), followed by GE-Imatron electron-beam (116.0 HU) and GE LightSpeed multi-detector row scanners (121.5 HU). Values were also lower for morbidly obese (BMI, >= 40.0 kg/m(2)) participants (108.9 HU), followed by obese (BMI, 30.0-39.9 kg/m(2)) (114.8 HU), overweight (BMI, 25.0-29.9 kg/m(2)) (118.5 HU), and normal-weight or underweight (BMI,