部分容积效应对双探头符合探测图像的影响  

Influence of partial volume effect on dual-head coincidence FDG images

作　　者：耿建华[1] 陈盛祖[1] 陈英茂[2] 朱继庆[1] 曹秀华[1] 赵卫强[1] 

机构地区：[1]中国医学科学院,中国协和医科大学肿瘤医院核医学科,北京100021 [2]解放军总医院核医学科

出　　处：《中华核医学杂志》2003年第4期247-249,共3页Chinese Journal of Nuclear Medicine

摘　　要：目的　探讨双探头符合探测 (DHC)图像中热灶的部分容积效应。方法　双探头符合探测设备 :GEHawkeye。模型 :东芝AZ 6 18ECT模型。核素 :1 8F 脱氧葡萄糖 (FDG) ,活度为 2 0 4～ 15MBq ,分 18次扫描。图像重建 :OSEM ,Hanning后滤波。由模型热灶区的重建数据确定热灶的恢复系数及半高宽 ,分析部分容积效应。结果　①恢复系数随热灶增大而减小 ;②同一热灶的恢复系数随感兴趣区增大而减小 ;③热灶恢复系数随其实际放射性浓度增高而降低 ;④热灶半高宽随其实际放射性浓度增加而展宽。结论　DHC图像的部分容积效应随病灶减小和病灶放射性浓度增加而增强。Objective To investigate the partial volume effect (PVE) on the dual-head coincidence (DHC) FDG images. Methods Eighteen times of emission scanning were performed with different levels of radioactive concentration, 4.33～58.38 kBq/ml (total radioactivity 15～204 MBq) on a cylindrical phantom using DHC system (GE Millennium VG Hawkeye). The images were reconstructed using OSEM algorithm with post filter Hanning (cutoff frequency, 0.6). Results The results showed the hot lesion recovery coefficient decreased with the escalation of the lesion size, the region of interest drawn and the true radioactive concentration; and their full width at half maximum increased with the escalation of the radioactive concentration. Conclusion PVE is related to the radioactive concentration as well as the size of the lesion; it increases along with the escalation of the radioactive concentration and the decrement in the lesion size.

关 键 词：双探头符合探测图像 部分容积效应 模型 肿瘤 放射疗法 热灶 

分 类 号：R817[医药卫生—影像医学与核医学]