NEMA NU 2 performance tests for scanners with intrinsic radioactivity.
NEMA NU 2 performance tests for scanners with intrinsic radioactivity.
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针对具有内在放射性的扫描仪的 NEMA NU 2 性能测试。
DOI：
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发表时间：
2004
影响因子：
9.3
通讯作者：
B. Bendriem
中科院分区：
文献类型：
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作者：
C. Watson;M. Casey;L. Eriksson;T. Mulnix;Doug Adams;B. Bendriem
氧化硅酸镥（LSO）基PET扫描仪的性能测试不能严格按照美国国家电气制造商协会（NEMA） NU 2标准进行，因为LSO晶体闪烁体材料存在本征放射性。这种背景辐射主要引起随机的巧合事件，但也引起少数真正的巧合，这些巧合不能从这种扫描仪的测量中消除，因此必须在数据分析中加以纠正。目前的NU 2标准没有考虑到这些背景，因此在基于lso的机器上可能导致错误的结果。然而，标准的意图可以通过对获取和处理程序的适当修改来满足。在本文中，我们建议对NEMA规范进行某些更改，以适应这类扫描仪。这些变化主要影响灵敏度、散点、随机和计数损失的估计。利用这些改进的程序，可以准确地测量基于lso的系统的NU 2性能。
Performance tests on lutetium oxyorthosilicate (LSO)-based PET scanners cannot be conducted strictly according to the National Electrical Manufacturers Association (NEMA) NU 2 standards because of the presence of intrinsic radioactivity within the LSO crystal scintillator material. This background radiation gives rise mainly to random coincidence events but also to a small number of true coincidences, which cannot be eliminated from measurements on such scanners and must therefore be corrected for in the data analysis. The current NU 2 standards do not take account of these backgrounds and hence can lead to erroneous results on LSO-based machines. Nevertheless, the intent of the standards can be met with appropriate modifications to the acquisition and processing procedures. In this paper, we propose certain changes to the NEMA specifications to accommodate this class of scanners. These changes affect mainly the estimation of sensitivity, scatter, randoms, and count losses. Using these modified procedures, the NU 2 performance of LSO-based systems can accurately be measured.