Karagounis Ilias V, Abatzoglou Ioannis M, Koukourakis Michael I
Department of Radiotherapy-Oncology, Radiopathology and Radiobiology Unit, Medical School, Democritus University of Thrace, Alexandroupolis 68100, Greece.
Medical Physics Department, University General Hospital of Alexandroupolis, Alexandroupolis 68100, Greece.
Med Phys. 2016 May;43(5):2200. doi: 10.1118/1.4945274.
In vivo radiobiology experiments involving partial body irradiation (PBI) of mice are of major importance because they allow for the evaluation of individual organ tolerance; overcoming current limitations of experiments using lower dose, whole body irradiation. In the current study, the authors characterize and validate an effective and efficient apparatus for multiple animal PBI, directed to the head, thorax, or abdomen of mice.
The apparatus is made of polymethylmethacrylate and consists of a rectangular parallelepiped prism (40 cm × 16 cm × 8 cm), in which five holes were drilled to accomodate standard 60 ml syringes, each housing an unanesthetized, fully immobilized mouse. Following CT-scanning and radiotherapy treatment planning, radiation fields were designed to irradiate the head, thorax, or abdomen of the animal. Thermoluminescent dosimeters (TLDs) were used to confirm the treatment planning dosimetry for primary beam and scattered radiation.
Mice are efficiently placed into 60 ml syringes and immobilized, without the use of anesthetics. Although partial rotational movement around the longitudinal axis and a minor 2 mm forward/backward movement are permitted, this does not compromise the irradiation of the chosen body area. TLDs confirmed the dose values predicted by the treatment planning dosimetry, both for primary beam and scattered radiation.
The customized PMMA apparatus described and validated is cost-effective, convenient to use, and efficient in performing PBI without the use of anesthesia. The developed apparatus permits the isolated irradiation of the mouse head, thorax, and abdomen. Importantly, the apparatus allows the delivery of PBI to five mice, simultaneously, representing an efficient way to effectively expose a large number of animals to PBI through multiple daily fractions, simulating clinical radiotherapy treatment schedules.
涉及小鼠局部身体照射（PBI）的体内放射生物学实验至关重要，因为它们有助于评估单个器官的耐受性，克服了当前低剂量全身照射实验的局限性。在本研究中，作者对一种用于对小鼠头部、胸部或腹部进行多次动物PBI的有效且高效的装置进行了表征和验证。
该装置由聚甲基丙烯酸甲酯制成，由一个长方体棱镜（40厘米×16厘米×8厘米）组成，其中钻有五个孔以容纳标准的60毫升注射器，每个注射器容纳一只未麻醉、完全固定的小鼠。在进行CT扫描和放射治疗治疗计划后，设计辐射野以照射动物的头部、胸部或腹部。使用热释光剂量计（TLD）来确认主束和散射辐射的治疗计划剂量测定。
小鼠能够高效地放入60毫升注射器中并固定，无需使用麻醉剂。虽然允许围绕纵轴进行部分旋转运动以及轻微的2毫米向前/向后运动，但这不会影响所选身体区域的照射。TLD证实了治疗计划剂量测定所预测的主束和散射辐射的剂量值。
所描述和验证的定制PMMA装置具有成本效益，使用方便，并且在不使用麻醉的情况下进行PBI高效。所开发的装置允许对小鼠头部、胸部和腹部进行单独照射。重要的是，该装置允许同时对五只小鼠进行PBI照射，这是一种通过多次每日分次有效地使大量动物接受PBI照射的有效方法，模拟了临床放射治疗方案。
