Department of Mechanical Engineering, Informatics and Chemistry of Polymer Materials, Faculty of Materials Technologies and Textile Design, Lodz University of Technology, Żeromskiego 116, 90-543 Lodz, Poland.
GeVero Co., 90-980 Lodz, Poland.
Molecules. 2024 May 29;29(11):2558. doi: 10.3390/molecules29112558.
This work describes the development of a reusable 2D detector based on radiochromic reaction for radiotherapy dosimetric measurements. It consists of a radiochromic gel dosimeter in a cuboidal plastic container, scanning with a flatbed scanner, and data processing using a dedicated software package. This tool is assessed using the example of the application of the coincidence test of radiation and mechanical isocenters for a medical accelerator. The following were examined: scanning repeatability and image homogeneity, the impact of image processing on data processing in coincidence tests, and irradiation conditions-monitor units per radiation beam and irradiation field are selected. Optimal conditions for carrying out the test are chosen: (i) the multi-leaf collimator gap should preferably be 5 mm for 2D star shot irradiation, (ii) it is recommended to apply ≥2500-≤5000 MU per beam to obtain a strong signal enabling easy data processing, (iii) Mean filter can be applied to the images to improve calculations. An approach to dosimeter reuse with the goal of reducing costs is presented; the number of reuses is related to the MUs per beam, which, in this study, is about 5-57 for 30,000-2500 MU per beam (four fields). The proposed reusable system was successfully applied to the coincidence tests, confirming its suitability as a new potential quality assurance tool in radiotherapy.
这项工作描述了一种基于放射性化学反应的可重复使用的 2D 探测器的开发，用于放射治疗剂量测量。它由一个立方体形塑料容器中的放射性化学凝胶剂量计组成，使用平板扫描仪进行扫描，并使用专用软件包进行数据处理。该工具通过应用辐射和机械等中心重合测试的实例来评估医疗加速器。研究了以下内容：扫描重复性和图像均匀性、图像处理对重合测试中数据处理的影响，以及照射条件——每个辐射束和照射野选择的监测单元。选择了进行测试的最佳条件：（i）对于 2D 星状射束照射，最好将多叶准直器间隙设置为 5mm；（ii）建议每束应用≥2500-≤5000MU，以获得强信号，便于数据处理；（iii）可以应用均值滤波器来改善计算。提出了一种剂量计重复使用的方法，以降低成本；重复使用的次数与每个束的 MU 有关，在这项研究中，每个束的 MU 为 30000-2500MU（四个野）时，约为 5-57。所提出的可重复使用系统成功应用于重合测试，证实了其作为放射治疗中新的潜在质量保证工具的适用性。
