Dynamic chest radiography for pulmonary function diagnosis: A validation study using 4D extended cardiac-torso (XCAT) phantom
Dynamic chest radiography for pulmonary function diagnosis: A validation study using 4D extended cardiac-torso (XCAT) phantom
复制标题
用于肺功能诊断的动态胸片：使用 4D 扩展心脏躯干 (XCAT) 模型的验证研究
DOI：
10.1117/12.2512332
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Kensaku Mori
中科院分区：
文献类型：
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作者：
Rie Tanaka;Ehsan Samei;William Paul Segars;Ehsan Abadi;Holger Roth;Hirohisa Oda;Kensaku Mori
本研究旨在研究使用4D扩展心脏躯干（XCAT）体模（具有用户定义的地面真实值）进行动态胸部X射线摄影时截留空气的检测性能。生成心率正常、缓慢用力呼吸和横膈膜运动的成年男性（身高和体重第50百分位）的XCAT体模。将空气球插入右肺以模拟肺气肿。使用X射线模拟器在10秒的整个呼吸周期内创建XCAT体模的连续胸片。在呼吸期间平移的每个网格状区域中测量像素值的呼吸变化，然后将与完全呼出图像的差异描绘为颜色映射图像，将较高的X射线透明度（增加的空气）表示为较高的颜色强度。使用各种尺寸的空气球，每个肺野和隔膜后面的检测性能进行了研究。结果表明，随着空气球大小的增加，呼吸像素值的变化减小，这取决于肺野。在彩色映射图像中，空气球被描绘为颜色缺陷，然而，那些在隔膜后面的是不可检测的。较小尺寸的采样将空气球描绘为岛状颜色缺陷，而较大尺寸的采样产生有限的信号。我们证实，动态胸部X线摄影能够检测到被困空气作为区域减少的变化，在呼吸过程中的像素值。减少率可以被定义为空气球前后的剩余正常组织的函数。
This study was performed to investigate the detection performance of trapped air in dynamic chest radiography using 4D extended cardiac-torso (XCAT) phantom with a user-defined ground truth. An XCAT phantom of an adult male (50th percentile in height and weight) with a normal heart rate, slow-forced breathing, and diaphragm motion was generated. An air sphere was inserted into the right lung to simulate emphysema. An X-ray simulator was used to create sequential chest radiographs of the XCAT phantom over a whole respiratory cycle covering a period of 10 seconds. Respiratory changes in pixel value were measured in each grid-like region translating during respiration, and differences from a fully exhaled image were then depicted as color-mapping images, representing higher X-ray translucency (increased air) as higher color intensities. The detection performance was investigated using various sizes of air spheres, for each lung field and behind the diaphragm. In the results, respiratory changes in pixel value were decreased as the size of air sphere increased, depending on the lung fields. In color-mapping images, air spheres were depicted as color defects, however, those behind the diaphragm were not detectable. Smaller size sampling depicted the air spheres as island color defects, while larger ones yielded a limited signal. We confirmed that dynamic chest radiography was able to detect trapped air as regionally-reduced changes in pixel value during respiration. The reduction rate could be defined as a function of residual normal tissue in front and behind air spheres.