Multivariate Compensation of Quantitative Pulmonary Emphysema Metric Variation From Low-Dose, Whole-Lung CT Scans
Multivariate Compensation of Quantitative Pulmonary Emphysema Metric Variation From Low-Dose, Whole-Lung CT Scans
复制标题
DOI：
10.2214/ajr.11.6444
复制
发表时间：
2011-09-01
影响因子：
5
通讯作者：
Yankelevitz, David F.
中科院分区：
文献类型：
--
作者：
Keller, Brad M.;Reeves, Anthony P.;Yankelevitz, David F.
OBJECTIVE.肺气肿是一种以肺泡囊壁破坏为特征的肺部疾病。全肺CT肺气肿的几种定量密度测量已被提出用于评估疾病的严重程度和进展。然而，这些定量测量的一个问题是在肺气肿的纵向研究中观察到的大的扫描间变异性。为了解释和减少固有的测量变异性，这项工作实施和评估使用多变量随机效应模型校正纵向变化的肺气肿由于inspiration.MATERIALS和方法的密度测量分数。多元补偿的方法进行了验证，对三个最常见的肺气肿密度测量：肺气肿指数，直方图百分位数，分形维数。两个短间隔，零变化数据集，一个用于模型开发（n = 105）和一个用于验证（n = 106），回顾性地确定和使用，以确保所有的变化是由固有的测量变异性。模型应用后，测量一致性限降低42.40%，具有统计学显著性（F检验，p < 0.001），与未补偿度量方差相比，补偿肺气肿度量差异显示31-33%的方差。当训练的模型应用于第二个验证数据集时，补偿仍然有效。多变量补偿被认为是有用的，在减少扫描间测量变异性，并应适用于未来的纵向研究肺气肿。
OBJECTIVE. Emphysema is a disease of the lung characterized by the destruction of the alveolar sac walls. Several quantitative densitometric measures of emphysema from whole-lung CT have been proposed for evaluating disease severity and progression. However, a concern with these quantitative measures has been the large interscan variability observed during longitudinal studies of emphysema. To account for and reduce inherent measure variability, this work implements and evaluates the use of a multivariate random-effects model for correcting longitudinal variation in densitometric scores of emphysema due to inspiration.MATERIALS AND METHODS. The method of multivariate compensation was validated on three of the most commonly reported densitometric measures of emphysema: the emphysema index, histogram percentile, and fractal dimension. Two short-interval, zero-change datasets, one for model development (n = 105) and one for validation (n = 106), were retrospectively identified and used to ensure that all variation was caused by inherent measure variability.RESULTS. A statistically significant (F test, p < 0.001) reduction of 42.40% in measurement limits of agreement could be obtained after model application, with compensated emphysema metric differences showing 31-33% of the variance compared with uncompensated metric variance.CONCLUSION. Compensation was still effective when the trained model was applied to the second validation dataset. Multivariate compensation was found to be useful in reducing interscan measurement variability and should be applied to future longitudinal studies of emphysema.