Sund Patrik, Båth Magnus, Kheddache Susanne, Månsson Lars Gunnar
Department of Radiation Physics, Göteborg University, 41345 Göteborg, Sweden.
Eur Radiol. 2004 Jan;14(1):48-58. doi: 10.1007/s00330-003-1971-z. Epub 2003 Oct 16.
A study was conducted to compare physical and clinical system performance in digital chest radiography. Four digital X-ray modalities, two storage-phosphor based systems and two generations of a CCD-based system, were evaluated in terms of both their imaging properties (determination of presampling MTF and DQE) and clinical image quality (grading of the reproduction of anatomical details of 23 healthy volunteers using both absolute and relative visual grading analysis). One of the two storage-phosphor systems performed best in both evaluations and the first generation of the CCD-based system was rated worst; however, the other two systems were ranked differently with the two methods. The newest CCD-based system yielded a higher clinical image quality than the second storage-phosphor system, although the latter presented a DQE substantially higher than the former. The results show that clinical performance cannot be predicted from determinations of DQE alone, and that a system with lower DQE, under the quantum-saturated conditions in chest radiography, can outperform a system with higher DQE if the image processing used on the former is more effective in presenting the information in the image to the radiologist.
开展了一项研究，以比较数字胸部X线摄影中的物理和临床系统性能。对四种数字X射线成像方式，即两种基于存储磷光体的系统和两代基于电荷耦合器件（CCD）的系统，在成像特性（预采样调制传递函数（MTF）和量子探测效率（DQE）的测定）和临床图像质量（使用绝对和相对视觉分级分析对23名健康志愿者的解剖细节再现进行分级）方面进行了评估。在两项评估中，两个基于存储磷光体的系统之一表现最佳，第一代基于CCD的系统评级最差；然而，另外两个系统在两种方法下的排名不同。最新的基于CCD的系统产生了比第二个基于存储磷光体的系统更高的临床图像质量，尽管后者的DQE明显高于前者。结果表明，仅通过DQE的测定无法预测临床性能，并且在胸部X线摄影的量子饱和条件下，如果用于前者的图像处理在向放射科医生呈现图像中的信息方面更有效，则DQE较低的系统可能优于DQE较高的系统。
