用于辐射剂量学应用的固体模体材料的水等效性。

Gargett Maegan A, Briggs Adam R, Booth Jeremy T

Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, NSW, Australia.

Institute of Medical Physics, University of Sydney, Sydney, NSW, Australia.

Phys Imaging Radiat Oncol. 2020 May 28;14:43-47. doi: 10.1016/j.phro.2020.05.003. eCollection 2020 Apr.

Radiological water equivalence of solid phantoms used for radiotherapy is often desired, but is non-trivial to achieve across the range of therapeutic energies. This study evaluated the water equivalence of a new solid phantom material in beam qualities relevant to radiotherapy applications. In-phantom measured depth distributions were compared to that in water to assess the relative attenuation and scatter characteristics of the material. The phantom material was found to be dosimetrically equivalent to water within (1.0 ± 1.0)% for megavoltage photon beam qualities, (1.5 ± 1.3)% for megavoltage electron beam qualities, (1.5 ± 1.5)% for medium-energy kilovoltage X-rays and (3.0 ± 1.5)% for low-energy kilovoltage X-rays.

用于放射治疗的固体模体的放射学水等效性常常是人们所期望的，但要在整个治疗能量范围内实现并非易事。本研究评估了一种新型固体模体材料在与放射治疗应用相关的射束质中的水等效性。将模体内测量的深度分布与水中的深度分布进行比较，以评估该材料的相对衰减和散射特性。结果发现，对于兆伏级光子射束质，该模体材料在剂量学上与水等效，偏差在(1.0 ± 1.0)%以内；对于兆伏级电子射束质，偏差在(1.5 ± 1.3)%以内；对于中能千伏级X射线，偏差在(1.5 ± 1.5)%以内；对于低能千伏级X射线，偏差在(3.0 ± 1.5)%以内。