Kume Y, Doi K
Kurt Rossmann Laboratories for Radiologic Image Research, Department of Radiology, University of Chicago, Illinois 60637.
Med Phys. 1987 Sep-Oct;14(5):736-43. doi: 10.1118/1.596148.
We are developing a digital x-ray imaging system using a multiple slit assembly (MSA) and an image intensifier (II)-TV digital system. The advantage of this approach is that the scatter from an object and the veiling glare in the II-TV system can be reduced significantly while the x-ray utilization is maintained much better than that with a single slit-beam technique. The quality of reconstructed images is related to many parameters such as the slit width, the lead spacer, the number of image frames, and the reconstruction algorithm. In this study, reduction of scatter and veiling glare was measured quantitatively, and image artifacts were analyzed. It was found that the fraction of scatter and veiling glare can be reduced to approximately 0.01-0.1 by use of the MSA imaging technique, and that the magnitude of the fractions is strongly dependent upon the slit width and the lead spacer of the MSA used. The artifacts are caused by inaccuracies in the slit width, lead spacer, and scan motion, and by undersampling of image data. The overlap scanning technique was effective in reducing the magnitude of these artifacts in the reconstructed image.
我们正在开发一种使用多狭缝组件（MSA）和图像增强器（II）-电视数字系统的数字X射线成像系统。这种方法的优点是，在保持X射线利用率比单狭缝束技术好得多的同时，物体的散射和II-电视系统中的散射光晕可以显著减少。重建图像的质量与许多参数有关，如狭缝宽度、铅间隔物、图像帧数和重建算法。在本研究中，对散射和散射光晕的减少进行了定量测量，并对图像伪影进行了分析。结果发现，通过使用MSA成像技术，散射和散射光晕的比例可以降低到大约0.01-0.1，并且这些比例的大小强烈依赖于所使用的MSA的狭缝宽度和铅间隔物。这些伪影是由狭缝宽度、铅间隔物和扫描运动的不准确以及图像数据的欠采样引起的。重叠扫描技术有效地降低了重建图像中这些伪影的大小。
