MC散射校正后的快速噪声抑制方法研究  

Fast Noise Suppression Method After Monte Carlo Based Scatter Correction for Cone-Beam CT

作　　者：李银[1] 徐圆[1] 齐宏亮[1] 李斌[1] 吴书裕[1] 周凌宏[1] 

机构地区：[1]南方医科大学生物医学工程学院医疗仪器研究所,广州510515

出　　处：《核电子学与探测技术》2015年第9期861-866,共6页Nuclear Electronics & Detection Technology

基　　金：国家自然科学基金(81301940;81428019);国家科技支撑计划(2015BAI01B10)资助

摘　　要：对于散射校正后的噪声抑制,提出一种基于泊松分布的投影平滑去噪方法。分别对真实机器数据以及仿真数据进行了实验,实验所用数据为一组骨盆(Pelvis)模体的CBCT投影,分辨率为512×385×656,体素大小为0.097 656 2×0.097 656 2×0.25 cm3。在仿真实验中,信噪比(SNR)从去噪前的19.8 d B提升至26.8 d B,同时均方根误差(RMSE)从去噪前的50.7降为22.5。在真实机器数据实验中,均方根误差(RMSE)从去噪前的64.1降至58.2。最后,实验中包括去散射以及去噪在内的整个过程保持在40 s之内完成。To restrain the noise after scattering correction, we get smooth objective function based on Poisson dis- tribution and statistics. Experiments of the real data and simulation data were performed separately in our meth- od. The phantom used in our experiments is a group of the CBCT projection of Pelvis. The resolution is 512 × 385 ×656,and the voxel is 0. 097 656 2 ×0.097 656 2 ×0.25 cm3. In the simulation case,the result shows that our method improves the SNR from 19.8 to 26.8 dB, and reduces RMSE from 50.7 to 22.5. In the real pa- tient case, our method reduces RMSE from 64.1 to 58.2. It should be noticed that the whole computation time in the process of our method is less than 40 s, which makes it possible to apply our method in clinical practice.

关 键 词：锥形束CT 噪声抑制 散射校正 蒙特卡洛方法 

分 类 号：TN911.73[电子电信—通信与信息系统]