Barnes G T, Brezovich I A
Med Phys. 1979 May-Jun;6(3):197-204. doi: 10.1118/1.594562.
A scanning multiple slit assembly (SMSA) has been constructed for the purpose of reducing scatter in medical radiography. The SMSA consists of a series of long, narrow beam-defining slits above the patient that are aligned and synchronously moved with scatter-eliminating slots beneath the patient during an exposure. Evidence, based on measurements of the ratio of scattered-to-primary radiation imaged and radiographs of patients, is presented indicating that such a device is a practical and efficient method of reducing scatter and improving contrast compared to conventional grids. The design considerations and trade-offs associated with the choice of slit width, slit separation distance, and aft slot depth are discussed along with the effect of these parameters on the SMSA's performance. The various problems encountered in obtaining a uniform scan and the manner in which they were handled are also discussed.
为减少医学放射成像中的散射，构建了一种扫描多狭缝组件（SMSA）。该SMSA由位于患者上方的一系列长而窄的束流限定狭缝组成，在曝光期间，这些狭缝与患者下方的散射消除狭槽对齐并同步移动。基于对成像的散射辐射与原发射线的比率测量以及患者的X光片给出的证据表明，与传统格栅相比，这种装置是一种减少散射和提高对比度的实用且有效的方法。讨论了与狭缝宽度、狭缝间距和后狭槽深度的选择相关的设计考虑因素和权衡，以及这些参数对SMSA性能的影响。还讨论了在获得均匀扫描过程中遇到的各种问题以及处理这些问题的方式。
