一种改善γ相机边缘定位结果的组合型定位算法

目的 提出一种有效解决在SPECT定位算法中提高图像边缘定位精度的新方法,以解决研制的小动物成像系统中存在的边缘图像畸变问题.方法 在系统分析几种常见的定位算法的基础上,提出一种组合型算法,在探测器平面的边缘区域采用一种特殊定位算法,而在非边缘区域采用基于最大似然的定位算法.结果 本方法在边缘区域的定位效果优于二维最大似然定位算法.结论 这种方法可以在实际系统中使用,以有效解决探测器边缘位置信息的畸变问题,达到提高投影图像定位精确度的目的.

A combined algorithm for improving the positioning result at the edge of γ camera

Objective To implement a combined method for the small animal CT-SPECT system to correct the distortion at the edge of the image, and to improve the positioning results. Methods At the edge of the scanner, a special estimator was used, and in the center of the scanner, maximum likelihood (ML) based method was used. Results Experiments showed that the positioning result of this method was better than those of two-dimensional ML. Conclusion The combined estimator can be used in reality to correct the distortion, and acquire more accurate projection data for SPECT.