Validation of computed tomographic lung densitometry for monitoring emphysema in α1-antitrypsin deficiency
Validation of computed tomographic lung densitometry for monitoring emphysema in α1-antitrypsin deficiency
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DOI：
10.1136/thx.2005.054890
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发表时间：
2006-06-01
期刊：
影响因子：
10
通讯作者：
Stockley, R. A.
中科院分区：
文献类型：
--
作者：
Parr, D. G.;Stoel, B. C.;Stockley, R. A.
背景：从计算机断层扫描图像得出的肺密度测定提供了非侵入性量化肺气肿的机会，但不能应用病理标准来验证其在纵向监测研究中的用途。因此，1 秒用力呼气量 (FEV1) 仍然是判断新方法的标准。在两项针对 α(1)-抗胰蛋白酶缺乏症 (PiZ) 受试者的研究中，我们将密度测定法的进展（第 15 个百分位点和体素指数，阈值 -950 Hounsfield 单位）与疾病阶段和 FEV1 下降联系起来。方法：在一项对 74 名受试者进行的为期 2 年的研究中，根据根据 GOLD 指南中采用的 FEV1 标准。在具有扩展数据的受试者亚组 (n = 34) 的第二项研究中，对 3 年内每年进行的测量进行汇总统计，密度测量的进展速率与 FEV1 下降相关。结果：百分位点的进展在广泛的疾病严重程度中是一致的，但体素指数进展随疾病阶段而变化 (p = 0.004)。在第二项研究中，FEV1 下降与肺密度测量进展相关（百分位点：r(S) = 0.527，p = 0.001；体素指数：r(S) = 20.398，p = 0.012）。结论：第 15 个百分位点是比体素指数更一致的衡量各种生理损伤的肺密度损失的指标。然而，这两种方法都适用于以肺气肿为主要结果目标的纵向和介入研究。
Background: Lung densitometry derived from computed tomographic images offers an opportunity to quantify emphysema non-invasively, but a pathological standard cannot be applied to validate its use in longitudinal monitoring studies. Consequently, forced expiratory volume in 1 second (FEV1) remains the standard against which new methods must be judged. We related progression of densitometry (15th percentile point and voxel index, threshold -950 Hounsfield units) to disease stage and FEV1 decline in two studies of subjects with alpha(1)-antitrypsin deficiency (PiZ).Methods: Consistency of progression, measured using densitometry and FEV1, was assessed in relation to disease stage in a 2 year study of 74 subjects grouped according to the FEV1 criteria employed in the GOLD guidelines. In the second study of a subgroup of subjects with extended data (n = 34), summary statistics were applied to measurements performed annually over 3 years and the rate of progression of densitometry was related to FEV1 decline.Results: The progression of percentile point was consistent across a wide spectrum of disease severity, but voxel index progression varied in association with disease stage (p = 0.004). In the second study, FEV1 decline correlated with progression of lung densitometry ( percentile point: r(S) = 0.527, p = 0.001; voxel index: r(S) = 20.398, p = 0.012).Conclusions: 15th percentile point is a more consistent measure of lung density loss across a wide range of physiological impairment than voxel index. However, both methods are valid for use in longitudinal and interventional studies in which emphysema is the major outcome target.