Kleen M, Habler O, Messmer K
Institute for Surgical Research, Klinikum Grosshadern Marchioininistr. Munich, Germany.
Comput Methods Programs Biomed. 1997 Jun;53(2):81-6. doi: 10.1016/s0169-2607(97)01808-7.
The radioactive microsphere method for determination of regional organ blood flow is widely used in experimental studies. The measurement error of this method in part depends on balanced activities from the set of nuclides used. Achieving even distribution of half-life corrected activity is tedious due to the many calculations needed and is limited by minimal and maximal allowable amounts of microspheres per injection. In two experiments we showed that incorrect planning of microspheres numbers can lead to invalidation of results. Therefore, we developed a program that allows optimization of half-life corrected activities and tested it on an experimental series of 16 dogs. Despite large discrepancies of specific activities of nuclides, storage times and half-lives, balancing activities with the program succeeded: on the average, the accumulated gamma spectra consisted of 22.3 +/- 6.9 85Sr, 18.9 +/- 6.8 141Ce, 10.7 +/- 6.2 51Cr, 23.9 +/- 6.7 95Nb, 16.9 +/- 7.2 46Sc, and 7.3 +/- 2.7% 114mIn radiation, respectively.
放射性微球法用于测定局部器官血流量，在实验研究中被广泛应用。该方法的测量误差部分取决于所用核素组的活度平衡。由于需要进行大量计算，实现半衰期校正活度的均匀分布很繁琐，并且每次注射的微球最小和最大允许量也限制了其实现。在两项实验中，我们表明微球数量规划不当会导致结果无效。因此，我们开发了一个程序，可优化半衰期校正活度，并在16只狗的实验系列中对其进行了测试。尽管核素的比活度、储存时间和半衰期存在很大差异，但使用该程序成功实现了活度平衡：平均而言，累积伽马谱分别由22.3±6.9%的85Sr、18.9±6.8%的141Ce、10.7±6.2%的51Cr、23.9±6.7%的95Nb、16.9±7.2%的46Sc和7.3±2.7%的114mIn辐射组成。
