Improved Diagnosis of Pulmonary Emphysema Using In Vivo Dark-Field Radiography
Improved Diagnosis of Pulmonary Emphysema Using In Vivo Dark-Field Radiography
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DOI：
10.1097/rli.0000000000000067
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发表时间：
2014-10-01
影响因子：
6.7
通讯作者：
Yildirim, Ali Oe.
中科院分区：
文献类型：
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作者：
Meinel, Felix G.;Yaroshenko, Andre;Yildirim, Ali Oe.
目的：本研究的目的是评估最近开发的基于光栅的 X 射线暗视野摄影方法是否可以提高体内肺气肿的诊断。材料和方法：使用气管内滴注猪胰腺弹性蛋白酶在雌性 C57BL/6N 小鼠中诱导肺气肿，并通过体内肺功能测试、组织病理学和定量形态测定法证实。小鼠被麻醉，但在成像过程中呼吸自由。实验使用原型小动物 X 射线暗场扫描仪进行，该扫描仪在 35 kV（峰值）下运行，10 个光栅步骤中每个步骤的曝光时间为 5 秒。视觉上比较图像。为了定量比较信号特征，将感兴趣区域放置在每个肺的上、中、下区域。进行接收器操作特征统计，以比较透射和暗场信号强度以及组合参数“归一化散射”区分健康和肺气肿肺的有效性。结果：健康小鼠和肺气肿小鼠之间的暗场图像存在明显的视觉差异。肺气肿小鼠和对照小鼠之间的 X 射线暗场信号和归一化散射的定量测量有显着差异，并且表现出良好的一致性与肺功能测试和定量组织学相比，归一化散射显示出比单独的暗视野（AUC，0.90；P = 0.01）或传输信号（AUC，0.69；P < 0.001）显着更高的辨别能力，可以很好地区分健康和肺气肿的肺区域。在小鼠模型中，X 射线暗场放射成像在体内技术上是可行的，并且在诊断肺气肿方面比传统的基于透射的 X 射线成像有了显着的改进。
Objectives: The purpose of this study was to assess whether the recently developed method of grating-based x-ray dark-field radiography can improve the diagnosis of pulmonary emphysema in vivo.Materials and Methods: Pulmonary emphysema was induced in female C57BL/6N mice using endotracheal instillation of porcine pancreatic elastase and confirmed by in vivo pulmonary function tests, histopathology, and quantitative morphometry. The mice were anesthetized but breathing freely during imaging. Experiments were performed using a prototype small-animal x-ray dark-field scanner that was operated at 35 kilovolt (peak) with an exposure time of 5 seconds for each of the 10 grating steps. Images were compared visually. For quantitative comparison of signal characteristics, regions of interest were placed in the upper, middle, and lower zones of each lung. Receiver-operating-characteristic statistics were performed to compare the effectiveness of transmission and dark-field signal intensities and the combined parameter "normalized scatter'' to differentiate between healthy and emphysematous lungs.Results: A clear visual difference between healthy and emphysematous mice was found for the dark-field images. Quantitative measurements of x-ray dark-field signal and normalized scatter were significantly different between the mice with pulmonary emphysema and the control mice and showed good agreement with pulmonary function tests and quantitative histology. The normalized scatter showed a significantly higher discriminatory power (area under the receiver-operating-characteristic curve [AUC], 0.99) than dark-field (AUC, 0.90; P = 0.01) or transmission signal (AUC, 0.69; P < 0.001) alone did, allowing for an excellent discrimination of healthy and emphysematous lung regions.Conclusions: In a murine model, x-ray dark-field radiography is technically feasible in vivo and represents a substantial improvement over conventional transmission-based x-ray imaging for the diagnosis of pulmonary emphysema.