STORAGE PHOSPHOR FILM FOR RADIATION THERAPY DOSIMETRY

描述（由申请人提供）：现代放射治疗模式，例如调强放射治疗（IMRT），与具有陡峭梯度的高度适形剂量分布相关。这些模式的调试需要使用多维剂量计，这些剂量计一直处于紧张的研究和开发之中。放射物理中心（RPC）最近的一份报告显示，大约有30%的机构未能提供一个剂量分布的头部和颈部体模，同意自己的治疗计划，在7%或4毫米。RPC报告提供了强有力的证据，调强放射治疗的实施是容易出错，需要改进的质量保证工具。这项研究的首要假设是，低Z KCl：Eu2+存储荧光膜（SPF）将提供第一个能够进行基准剂量测量的2D剂量计，大大提高放射治疗计划和输送系统的调试和质量保证。我们的第一个目标是优化KCl：Eu2+存储荧光粉颗粒组成和化学结构，以最大限度地提高辐射灵敏度，辐射硬度，响应均匀性和信号稳定性。我们的第二个目标是开发一种通过使用物理气相沉积将目标1中开发的优化的存储磷光体蒸发到大约一微米的厚度到几乎水等效的衬底上来制造SPF的方法。我们的第三个目标是证明，SPF剂量计的目标2中开发的将提供基准质量的剂量分布测量，并通过构建平面和圆柱形剂量计来证明SPF制造过程的灵活性。 公共卫生相关性：这项研究的成功完成将为放射肿瘤学界提供第一个能够获得基准剂量测量的二维剂量计原型。这对于安全和有效地利用现代复杂的辐射输送技术（如IMRT）至关重要。

DESCRIPTION (provided by applicant): Modern radiation therapy modalities, for example, intensity modulated radiation therapy (IMRT), are associated with highly conformal dose distributions with steep gradients. Commissioning of these modalities requires the use of multidimensional dosimeters which have been under intense research and development. A recent report from the Radiological Physics Center (RPC) revealed that roughly 30% of institutions failed to deliver a dose distribution to a head-and-neck phantom that agrees with their own treatment plan to within 7% or 4 mm. The RPC report provides strong evidence that IMRT implementation is prone to error and that improved quality assurance tools are required. The overarching hypothesis of this research is that a low-Z KCl:Eu2+ storage phosphor film (SPF) will provide the first 2D dosimeter capable of conducting benchmark dosimetry measurements, substantially improving the commissioning and quality assurance of radiation therapy treatment planning and delivery systems. Our first aim is to optimize KCl:Eu2+ storage phosphor particle composition and chemical structure to maximize radiation sensitivity, radiation hardness, response uniformity, and signal stability. Our second aim is to develop a process to fabricate an SPF by evaporating the optimized storage phosphor developed in aim 1 to a thickness on the order of one micron using physical vapor deposition onto a nearly water-equivalent substrate. Our third aim is to demonstrate that the SPF dosimeter developed in aim 2 will provide benchmark-quality dose distribution measurements and to demonstrate the flexibility of the SPF fabrication process by building planar and cylindrical dosimeters. PUBLIC HEALTH RELEVANCE: The successful completion of this research will provide the radiation oncology community with the first two-dimensional dosimeter prototype capable of acquiring benchmark dose measurements. This will be critical for the safe and efficient utilization of modern, complex radiation delivery techniques such as IMRT.