Departments of Radiation Physics.
Departments of The University of Texas MD Anderson Cancer Center, Houston, Texas.
Radiat Res. 2020 Apr;193(4):341-350. doi: 10.1667/RR15220.1. Epub 2020 Feb 18.
Dedicated precision orthovoltage small animal irradiators have become widely available in the past decade and are commonly used for radiation biology research. However, there is a lack of dosimetric standardization among these irradiators, which affects the reproducibility of radiation-based animal studies. The purpose of this study was to develop a mail-based, independent peer review system to verify dose delivery among institutions using X-RAD 225Cx irradiators (Precision X-Ray, North Branford, CT). A robust, user-friendly mouse phantom was constructed from high-impact polystyrene and designed with dimensions similar to those of a typical laboratory mouse. The phantom accommodates three thermoluminescent dosimeters (TLDs) to measure dose. The mouse peer review system was commissioned in a small animal irradiator using anterior-posterior and posterior-anterior beams of 225 kVp and then mailed to three institutions to test the feasibility of the audit service. The energy correction factor for TLDs in the mouse phantom was derived to validate the delivered dose using this particular animal irradiation system. This feasibility study indicated that three institutions were able to deliver a radiation dose to the mouse phantom within ±10% of the target dose. The developed mail audit independent peer review system for the verification of mouse dosimetry can be expanded to characterize other commercially available orthovoltage irradiators, thereby enhancing the reproducibility of studies employing these irradiators.
在过去的十年中，专用的高精度小动物辐照器已经广泛应用，并常用于辐射生物学研究。然而，这些辐照器之间缺乏剂量学标准化，这影响了基于辐射的动物研究的可重复性。本研究的目的是开发一种基于邮件的独立同行评审系统，以验证使用 X-RAD 225Cx 辐照器（Precision X-Ray，North Branford，CT）的机构之间的剂量传递。一个由高冲击聚苯乙烯制成的强大、用户友好的小鼠体模，其尺寸与典型的实验室小鼠相似。体模可容纳三个热释光剂量计（TLD）以测量剂量。小鼠同行评审系统在一台小动物辐照器中进行了委托，使用 225kVp 的前后和后前射线，并邮寄给三个机构，以测试审计服务的可行性。从 TLD 在小鼠体模中的能量校正因子推导而来，以验证使用该特定动物辐照系统的传递剂量。这项可行性研究表明，三个机构能够将辐射剂量递送到小鼠体模中，与目标剂量的偏差在±10%以内。开发的用于验证小鼠剂量学的邮件审核独立同行评审系统可以扩展到描述其他市售的正交辐照器，从而提高使用这些辐照器的研究的可重复性。
