基于LYSO正电子发射乳腺断层成像系统探测器的设计与评估  

Design and evaluation of positron emission mammography based on LYSO

作　　者：胡均松[1] 邓明亮[1] 王新增[1] 汪梦蝶[1] 刘懿龙[1] 胡广书[1] 张辉[1] 

机构地区：[1]清华大学医学院生物医学工程系,北京100084

出　　处：《核技术》2013年第10期44-51,共8页Nuclear Techniques

摘　　要：本文介绍了一种平板正电子发射乳腺断层成像系统的探测器设计与评估方法。该探测器的闪烁晶体材料为LYSO,晶体阵列包含22×74个晶条,晶条的中心间距为2 mm,晶体厚度为10 mm,探测器有效成像面积为44 mm×148.56 mm,晶体阵列被耦合在3个并排的H8500上。该探测器由两个平行相对的探头构成,两侧探头相距17.4 cm。其中一侧探测器晶体单元的能量分辨率为10.54%–19.84%,平均能量分辨率为13.34%。另一侧探测器晶体单元的能量分辨率为11.75%–33.72%,平均能量分辨率为14.17%。该探测器符合事件的时间分辨率为2.6 ns,有效符合事件计数率约为21×103s 1。探测器在长轴和短轴的图像空间分辨率分别为1.14 mm和1.20 mm。测试结果表明,该探测器与设计预期相符,为早期乳腺癌的检测提供了可能。Background： Developing a style of special imaging device, such as positron emission mammography, is very important for early-stage breast cancer detection and cure. Purpose： The aim is to design planar detectors for positron emission mammography. Methods： The detector was segmented into a pixilated array consisting of 22×74 elements. Its crystal pitch and crystal cross section are 2 mm and 1.88 mm×1.88 ram, respectively. The effective area is 44 mm^2 148.56 mm. The array is coupled to 3 Hamamatsu H8500 position sensitive photomultiplier tubes in neck and neck way. Results： For left detector head, its energy resolution ranged from 10.54% to 19.84% full width of maximum （FWHM）, with a mean of 13.34%. For right head, its energy resolution ranged from 11.75% to 33.72% FWHM, with a mean of 14.17%. Coincidence timing resolution for the detector pair is measured to be 2.6 ns FWHM. Effective prompt event rate is 21 × 103 s-1. The image spatial resolutions in X and Y direction are 1.14 mm and 1.20 mm, respectively. Conclusion： The results show that the planar detectors of positron emission mammography are suitable for detecting early-stage breast cancer.

关 键 词：正电子发射乳腺断层成像 硅酸钇镥闪烁晶体 位置灵敏光电倍增管 均衡电荷分配电路 探测器 

分 类 号：TL81[核科学技术—核技术及应用]