Archambault Louis, Arsenault Jean, Gingras Luc, Sam Beddar A, Roy René, Beaulieu Luc
Département de Radio-Oncologie et Centre de Recherche en Cancérologie, Hôtel-Dieu de Québec, 11 côte du palais, Québec, Québec G1R 2J6, Canada, and Département de Physique, de Génie Physique et d'Optique, Université Laval, Québec, Québec Canada.
Department of Radiation Physics, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030.
Med Phys. 2005 Jul;32(7Part1):2271-2278. doi: 10.1118/1.1943807.
Scintillation dosimetry is a promising avenue for evaluating dose patterns delivered by intensity-modulated radiation therapy plans or for the small fields involved in stereotactic radiosurgery. However, the increase in signal has been the goal for many authors. In this paper, a comparison is made between plastic scintillating fibers and plastic scintillator. The collection of scintillation light was measured experimentally for four commercial models of scintillating fibers (BCF-12, BCF-60, SCSF-78, SCSF-3HF) and two models of plastic scintillators (BC-400, BC-408). The emission spectra of all six scintillators were obtained by using an optical spectrum analyzer and they were compared with theoretical behavior. For scintillation in the blue region, the signal intensity of a singly clad scintillating fiber (BCF-12) was 120% of that of the plastic scintillator (BC-400). For the multiclad fiber (SCSF-78), the signal reached 144% of that of the plastic scintillator. The intensity of the green scintillating fibers was lower than that of the plastic scintillator: 47% for the singly clad fiber (BCF-60) and 77% for the multiclad fiber (SCSF-3HF). The collected light was studied as a function of the scintillator length and radius for a cylindrical probe. We found that symmetric detectors with nearly the same spatial resolution in each direction (2 mm in diameter by 3 mm in length) could be made with a signal equivalent to those of the more commonly used asymmetric scintillators. With augmentation of the signal-to-noise ratio in consideration, this paper presents a series of comparisons that should provide insight into selection of a scintillator type and volume for development of a medical dosimeter.
闪烁剂量学是评估调强放射治疗计划所传递的剂量模式或立体定向放射外科中涉及的小射野的一个有前景的途径。然而，提高信号强度一直是许多作者的目标。本文对塑料闪烁光纤和塑料闪烁体进行了比较。对四种商用型号的闪烁光纤（BCF - 12、BCF - 60、SCSF - 78、SCSF - 3HF）和两种型号的塑料闪烁体（BC - 400、BC - 408）的闪烁光收集情况进行了实验测量。使用光谱分析仪获得了所有六种闪烁体的发射光谱，并将其与理论行为进行了比较。对于蓝光区域的闪烁，单包层闪烁光纤（BCF - 12）的信号强度是塑料闪烁体（BC - 400）的120%。对于多包层光纤（SCSF - 78），信号达到了塑料闪烁体的144%。绿色闪烁光纤的强度低于塑料闪烁体：单包层光纤（BCF - 60）为47%，多包层光纤（SCSF - 3HF）为77%。研究了圆柱形探头中收集光随闪烁体长度和半径的变化情况。我们发现可以制造出在每个方向上具有几乎相同空间分辨率（直径2 mm，长度3 mm）的对称探测器，其信号与更常用的不对称闪烁体相当。考虑到信噪比的提高，本文进行了一系列比较，这些比较应能为医疗剂量计开发中闪烁体类型和体积的选择提供参考。
