Improved image quality utilizing dual plate computed radiography.
Improved image quality utilizing dual plate computed radiography.
复制标题
利用双板计算机射线照相术提高图像质量。
DOI：
10.1259/0007-1285-68-806-182
复制
发表时间：
1995
期刊：
影响因子：
--
通讯作者：
A. Cowen
中科院分区：
文献类型：
--
作者：
A. Workman;A. Cowen
提出了一种利用双底片曝光提高计算机放射成像（CR）图像质量的方法。使用两个CR成像板来增加从光束中吸收的x射线量子的比例。空间配准和组合的图像从两个板导致图像具有改进的信噪比特性。采用互相关技术对前后板图像进行空间配准。测量了单片和双片组合图像的调制传递函数和噪声功率谱。结果表明，与单片图像相比，双片组合图像的探测量子效率（DQE）可能提高约60%。在高空间频率下，DQE的改进取决于两幅图像的配准精度。成像性能的实际改进是使用对比度细节测试片来测量的。采用计算机化方法测量不同尺寸的图像细节信噪比。结果表明，与单板相比，双板排列成像细节的信噪比提高了21%。这表明，在相同的曝光水平下，这种技术可以显著提高图像质量。另外，这种技术可以减少曝光，同时保持与单版系统相同的图像质量。
A method of improving image quality in computed radiography (CR) using dual plate exposure has been developed. Two CR image plates are used to increase the fraction of X-ray quanta absorbed from the beam. Spatial registration and combination of images from the two plates leads to an image with improved signal-to-noise ratio characteristics. A cross correlation technique is used to register spatially the images from the front and rear plates. The modulation transfer function and noise power spectrum were measured for the single plate and combined dual plate images. Results indicate a potential increase of approximately 60% in the detective quantum efficiency (DQE) of the dual plate combined image compared with the single plate image. The improvement of DQE at high spatial frequencies is dependent on the accuracy of the registration of the two images. The actual improvement in imaging performance was measured using a contrast detail test piece. A computerized method was used to measure the imaged detail signal-to-noise ratio of the details of different dimension. Results indicate an improvement of 21% in the signal-to-noise ratio of the details imaged with the dual plate arrangement compared with the single plate. This indicates that this technique can result in a significant increase in image quality for the same exposure level. Alternatively this technique could allow reduction in exposure while maintaining the same image quality achievable with the single plate system.