Veldkamp Wouter J H, Kroft Lucia J M, Mertens Bart J A, Geleijns Jacob
Department of Radiology, C2S, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands.
Radiology. 2005 Jun;235(3):857-66. doi: 10.1148/radiol.2353031919. Epub 2005 Apr 21.
To evaluate the image quality and performance of a chest digital radiography system and to compare this with the image quality and performance of advanced multiple-beam equalization radiography (AMBER) and Bucky screen-film radiography systems.
The chest digital radiography system is a digital charge-coupled device (CCD) chest imaging unit that uses slot-scan technology. A contrast-detail test object was used in combination with a phantom that simulates the primary and scatter transmission for the lungs and mediastinum. Twelve phantom images were obtained with each modality (ie, CCD digital radiography and AMBER and Bucky screen-film radiography) and were judged by six observers. CCD digital radiography soft-copy reading was compared with AMBER hard-copy reading. To measure image quality, contrast-detail curves were constructed from the observer data. The Wilcoxon signed rank test was used for statistical analysis.
For the lung configuration, contrast-detail curves showed lower threshold depth for hard-copy images obtained with CCD digital radiography than for those obtained with Bucky screen-film radiography. For hard-copy images, the difference between contrast-detail curves for CCD digital radiography and those for Bucky screen-film radiography was statistically significant (P < .006). No significant difference was found between CCD digital radiography and AMBER for hard-copy images obtained in either the lung or mediastinum configuration. For the lung configuration, a lower threshold depth was observed for CCD digital radiography soft-copy reading than for AMBER hard-copy reading, with significantly different contrast-detail curves for CCD digital radiography soft copy and AMBER hard copy (P < .006). No significant difference was found between either system for the mediastinum configuration.
Contrast-detail curves indicate that image quality for the CCD chest system provides a digital alternative to AMBER and Bucky screen-film radiography.
评估胸部数字X线摄影系统的图像质量和性能，并将其与先进的多束均衡X线摄影（AMBER）和滤线器屏-片X线摄影系统的图像质量和性能进行比较。
胸部数字X线摄影系统是一种采用狭缝扫描技术的数字电荷耦合器件（CCD）胸部成像单元。将对比细节测试物体与模拟肺部和纵隔的一次及散射传输的体模相结合使用。每种成像方式（即CCD数字X线摄影、AMBER和滤线器屏-片X线摄影）均获取12张体模图像，并由6名观察者进行评判。将CCD数字X线摄影的软拷贝阅读与AMBER的硬拷贝阅读进行比较。为测量图像质量，根据观察者数据构建对比细节曲线。采用Wilcoxon符号秩检验进行统计分析。
对于肺部结构，对比细节曲线显示，与滤线器屏-片X线摄影获得的硬拷贝图像相比，CCD数字X线摄影获得的硬拷贝图像的阈值深度更低。对于硬拷贝图像，CCD数字X线摄影与滤线器屏-片X线摄影的对比细节曲线之间的差异具有统计学意义（P <.006）。在肺部或纵隔结构中获得的硬拷贝图像，CCD数字X线摄影与AMBER之间未发现显著差异。对于肺部结构，观察到CCD数字X线摄影软拷贝阅读的阈值深度低于AMBER硬拷贝阅读，CCD数字X线摄影软拷贝与AMBER硬拷贝的对比细节曲线存在显著差异（P <.006）。对于纵隔结构，两种系统之间均未发现显著差异。
对比细节曲线表明，CCD胸部系统的图像质量为AMBER和滤线器屏-片X线摄影提供了一种数字替代方案。
