Hu B, Wang Y, Zealey W
Centre of Medical Radiation Physics, School of Engineering Physics, University of Wollongong, Sydney, Australia.
Australas Phys Eng Sci Med. 2009 Dec;32(4):226-32. doi: 10.1007/BF03179243.
A commercial Optical Stimulated Luminescence (OSL) dosimetry system developed by Landauer was tested to analyse the possibility of using OSL dosimetry for external beam radiotherapy planning checks. Experiments were performed to determine signal sensitivity, dose response range, beam type/energy dependency, reproducibility and linearity. Optical annealing processes to test OSL material reusability were also studied. In each case the measurements were converted into absorbed dose. The experimental results show that OSL dosimetry provides a wide dose response range, good linearity and reproducibility for the doses up to 800cGy. The OSL output is linear with dose up to 600cGy range showing a maximum deviation from linearity of 2.0% for the doses above 600cGy. The standard deviation in response of 20 dosimeters was 3.0%. After optical annealing using incandescent light, the readout intensity decreased by approximately 98% in the first 30 minutes. The readout intensity, I, decreased after repeated optical annealing as a power law, given by I infinity t (-1.3). This study concludes that OSL dosimetry can provide an alternative dosimetry technique for use in in-vivo dosimetry if rigorous measurement protocols are established.
对Landauer公司研发的一款商用光激发发光（OSL）剂量测定系统进行了测试，以分析将OSL剂量测定法用于外照射放疗计划检查的可能性。开展实验以确定信号灵敏度、剂量响应范围、射束类型/能量依赖性、再现性和线性。还研究了用于测试OSL材料可重复使用性的光退火过程。在每种情况下，测量结果都被转换为吸收剂量。实验结果表明，对于高达800cGy的剂量，OSL剂量测定法具有较宽的剂量响应范围、良好的线性和再现性。在高达600cGy的剂量范围内，OSL输出与剂量呈线性关系，对于高于600cGy的剂量，其与线性的最大偏差为2.0%。20个剂量计响应的标准偏差为3.0%。使用白炽灯进行光退火后，在前30分钟内读出强度下降了约98%。重复光退火后，读出强度I以幂律形式下降，即I∝t^(-1.3)。本研究得出结论，如果建立严格的测量方案，OSL剂量测定法可为体内剂量测定提供一种替代剂量测定技术。
