Mohyedin Muhammad Zamir, Zin Hafiz Mohd, Adenan Mohd Zulfadli, Abdul Rahman Ahmad Taufek
School of Physics and Material Studies, Faculty of Applied Sciences, Universiti Teknologi MARA, Shah Alam 40450, Selangor, Malaysia.
Centre of Astrophysics & Applied Radiation, Institute of Science, Universiti Teknologi MARA, Shah Alam 40450, Selangor, Malaysia.
Polymers (Basel). 2022 Jul 16;14(14):2887. doi: 10.3390/polym14142887.
Recent advances in radiotherapy technology and techniques have allowed a highly conformal radiation to be delivered to the tumour target inside the body for cancer treatment. A three-dimensional (3D) dosimetry system is required to verify the accuracy of the complex treatment delivery. A 3D dosimeter based on the radiochromic response of a polymer towards ionising radiation has been introduced as the PRESAGE dosimeter. The polyurethane dosimeter matrix is combined with a leuco-dye and a free radical initiator, whose colour changes in proportion to the radiation dose. In the previous decade, PRESAGE gained improvement and enhancement as a 3D dosimeter. Notably, PRESAGE overcomes the limitations of its predecessors, the Fricke gel and the polymer gel dosimeters, which are challenging to fabricate and read out, sensitive to oxygen, and sensitive to diffusion. This article aims to review the characteristics of the radiochromic dosimeter and its clinical applications. The formulation of PRESAGE shows a delicate balance between the number of radical initiators, metal compounds, and catalysts to achieve stability, optimal sensitivity, and water equivalency. The applications of PRESAGE in advanced radiotherapy treatment verifications are also discussed.
放射治疗技术和技巧的最新进展使得在癌症治疗中能够将高度适形的辐射传递到体内的肿瘤靶区。需要一种三维（3D）剂量测定系统来验证复杂治疗传递的准确性。一种基于聚合物对电离辐射的放射变色响应的3D剂量计已作为PRESAGE剂量计被引入。聚氨酯剂量计基质与无色染料和自由基引发剂相结合，其颜色变化与辐射剂量成比例。在过去十年中，PRESAGE作为一种3D剂量计得到了改进和增强。值得注意的是，PRESAGE克服了其前身弗里克凝胶和聚合物凝胶剂量计的局限性，后者在制造和读出方面具有挑战性，对氧气敏感，且对扩散敏感。本文旨在综述放射变色剂量计的特性及其临床应用。PRESAGE的配方在自由基引发剂、金属化合物和催化剂的数量之间显示出微妙的平衡，以实现稳定性、最佳灵敏度和水等效性。还讨论了PRESAGE在先进放射治疗验证中的应用。
