A Robust Emphysema Severity Measure Based on Disease Subtypes
A Robust Emphysema Severity Measure Based on Disease Subtypes
复制标题
DOI：
10.1016/j.acra.2015.12.021
复制
发表时间：
2016-04-01
影响因子：
4.8
通讯作者：
Estepar, Raul San Jose
中科院分区：
文献类型：
--
作者：
Harmouche, Rola;Ross, James C.;Estepar, Raul San Jose
理论基础和目的：我们提出了一种新的单一指标，用于量化肺气肿严重程度，其基础是聚集了吸烟者肺实质中明显的多个计算机断层扫描特征。我们的目标是证明这一单一指数提供了对当前肺气肿标准测量的补充信息，肺气肿百分比(低密度面积百分比[LAA%])，并可能在其与临床相关结果的相关性方面更好。材料和方法：我们算法的输入是对多种肺气肿亚型(正常组织；全小叶；隔旁；以及轻度、中度和重度小叶中心型肺气肿)的客观评估。我们将降维技术应用于肺气肿的数量，以找到使这些亚型的方差最大化的空间。然后，从缩小的空间的参数化导出单个肺气肿严重程度指数，并在来自COPD基因研究的8914名受试者的大型横断面队列中探索该测量的临床实用性。结果：严重程度指数与LAA%之间存在统计学意义的关联。慢性阻塞性肺疾病越严重(阻塞性肺疾病全球主动性越高)的受试者往往有更高的CT严重程度指数。最后，严重程度指数与临床结果，如肺功能，并提供了比LAA%更强的相关性。结论：该方法提供了一个单一的临床相关指数，可以评估肺气肿的严重程度，并提供了补充更常用的LAA%的信息。
Rationale and Objectives: We propose a novel single index for the quantification of emphysema severity based on an aggregation of multiple computed tomographic features evident in the lung parenchyma of smokers. Our goal was to demonstrate that this single index provides complementary information to the current standard measure of emphysema, percent emphysema (percent low attenuation areas [LAA%]), and may be superior in its association with clinically relevant outcomes.Materials and Methods: The inputs to our algorithm were objective assessments of multiple emphysema subtypes (normal tissue; panlobular; paraseptal; and mild, moderate, and severe centrilobular emphysema). We applied dimensionality reduction techniques to the emphysema quantities to find a space that maximizes the variance of these subtypes. A single emphysema severity index was then derived from a parametrization of the reduced space, and the clinical utility of the measure was explored in a large cross-sectional cohort of 8914 subjects from the COPDGene Study.Results: There was a statistically significant association between the severity index and the LAA%. Subjects with more severe chronic obstructive pulmonary disease (higher Global initiative for Obstructive Lung Disease stage) tended to have a higher computed tomography severity index. Finally, the severity index was associated with clinical outcomes such as lung function and provided a stronger association to these measures than the LAA%.Conclusions: The method provides a single clinically relevant index that can assess the severity of emphysema and that provides information that is complimentary to the more commonly used LAA%.