Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
Phys Med Biol. 2012 Nov 7;57(21):7147-59. doi: 10.1088/0031-9155/57/21/7147. Epub 2012 Oct 12.
The goal of this study was to develop a novel multi-point plastic scintillation detector (mPSD) capable of measuring the dose accurately at multiple positions simultaneously using a single optical transmission line. A 2-point mPSD used a band-pass approach that included splitters, color filters and an EMCCD camera. The 3-point mPSD was based on a new full-spectrum approach, in which a spectrograph was coupled to a CCD camera. Irradiations of the mPSDs and of an ion chamber were performed with a 6 MV photon beam at various depths and lateral positions in a water tank. For the 2-point mPSD, the average relative differences between mPSD and ion chamber measurements for the depth-dose were 2.4±1.6% and 1.3±0.8% for BCF-60 and BCF-12, respectively. For the 3-point mPSD, the average relative differences over all conditions were 2.3±1.1%, 1.6±0.4% and 0.32±0.19% for BCF-60, BCF-12 and BCF-10, respectively. This study demonstrates the practical feasibility of mPSDs. This type of detector could be very useful for pre-treatment quality assurance applications as well as an accurate tool for real-time in vivo dosimetry.
本研究旨在开发一种新型多点塑料闪烁探测器（mPSD），该探测器能够使用单根光学传输线同时在多个位置精确测量剂量。两点 mPSD 使用带通方法，包括分光器、滤光片和 EMCCD 相机。三点 mPSD 基于新的全谱方法，其中将光谱仪与 CCD 相机耦合。在水箱中的不同深度和横向位置，使用 6MV 光子束对 mPSD 和离子室进行了照射。对于两点 mPSD，mPSD 和离子室测量的深度剂量的平均相对差异分别为 BCF-60 和 BCF-12 的 2.4±1.6%和 1.3±0.8%。对于三点 mPSD，所有条件下的平均相对差异分别为 BCF-60、BCF-12 和 BCF-10 的 2.3±1.1%、1.6±0.4%和 0.32±0.19%。本研究证明了 mPSD 的实际可行性。这种探测器对于治疗前质量保证应用以及实时体内剂量测量是非常有用的精确工具。
