SBIR Phase I: Medical Devices for Real-time Radiation Dosimetry at Sub-millimeter Spatial Resolution

这个小企业创新研究第一阶段项目旨在开发一种新型剂量计，用于亚毫米空间分辨率下实时的二维辐射剂量测绘。高空间分辨率的剂量计在支持立体定向放射外科（SRS）和立体定向全身放射治疗（SBRT）治疗中至关重要。这些快速出现的方式提供精确剂量的辐射小，明确的治疗部位，同时尽量减少暴露的关键邻近解剖。随着每年SRS/SBRT治疗的数量接近100万，并以每年5-10%的速度增长，市场对亚毫米分辨率和实时测量能力的剂量计有需求。对每个患者治疗方案的常规治疗前验证成为目标应用。仅剂量计的市场价值每年就超过1000万美元。通过安全有效地提供SRS和SBRT治疗，其价值被放大。这些方式的使用大大减少了治疗过程中单个疗程的次数，从而极大地影响了放射治疗的效率。最终结果是治疗过程的成本降低，每个线性加速器设备单元每年的患者数量增加，并且报告了患者预后的大量改善。这个项目的智力价值在于结合和调整两种成熟的商业技术的关键要素，压电聚合物和放射性致色膜，以生产混合剂量计。该剂量计保留了放射性变色胶片的高空间分辨率，同时提高了其可用性，使辐射暴露引起的变化可以通过电子手段实时检测到。在使用过程中，这种灵活的、一次性使用的压电阵列剂量计（PARD）安装在一个可重复使用的数据采集电子模块中，该模块将测量剂量的地图传输给辐射细胞外的医学物理学家。放射致色膜是目前唯一具有亚毫米空间分辨率的剂量计，由于曝光和测量之间的长时间延迟以及方便测量所需的额外时间和精力，因此不方便。这个缺点不利地影响了它在患者治疗计划的日常验证中的有用性。混合PARD产品提供了密集、灵活的探测器阵列（0.1 mm间距），具有亚毫米分辨率实时剂量测量的独特能力。这克服了现有电子阵列设备的主要缺点，即无法实现低于5毫米的空间分辨率，并且不适合与SRs和SBRT处理相关的小辐射场。

This Small Business Innovation Research Phase I project seeks development of a novel dosimeter for 2-D mapping of radiation dose in real-time at sub-millimeter spatial resolution. The high spatial resolution of the dosimeter is essential in supporting stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT) treatments. These rapidly emerging modalities deliver precise doses of radiation to small, well defined treatment sites while minimizing exposure of critical neighboring anatomy. With the annual number of SRS/SBRT treatments approaching 1,000,000 and growing 5-10% annually there is a market need for a dosimeter with sub-millimeter resolution and the capability of measuring in real-time. The routine pre-treatment verification of each patient therapy plan becomes a target application. The value of the market for the dosimeter alone exceeds $10 million annually. The value is amplified through enablement of the safe and efficacious delivery of SRS and SBRT treatments. Use of these modalities greatly impacts the efficiency of radiotherapy by substantially reducing the number of individual sessions in a course of treatment. The net result is lower cost for the treatment course, an increase in the number of patients/year for each linear accelerator equipment unit and a large reported improvement in patient outcomes. The intellectual merit of this project lies in combining and adapting key elements of two well-established commercial technologies, piezoelectric polymers and radiochromic film, to produce a hybrid dosimeter. This dosimeter preserves the high spatial resolution of radiochromic film while improving its usability by making the changes caused by radiation exposure to become detectable by electronic means in real-time. During use, the flexible, single-use piezoelectric array dosimeter (PARD) fits into a re-usable data acquisition electronics module that transmits a map of measured doses to a Medical Physicist outside the radiation cell. Radiochromic film, the only current dosimeter with sub-millimeter spatial resolution, is inconvenient owing to the long delay between exposure and measurement as well as the extra time and effort in facilitating the measurements. This drawback adversely impacts its usefulness in the day-to-day verification of patient treatment plans. The hybrid PARD product provides a dense, flexible array (0.1 mm spacing) of detectors with the unique ability for dose measurement at sub-millimeter resolution in real time. This overcomes key drawbacks of existing electronic array devices which are incapable of spatial resolution below 5 mm and unsuitable for the small radiation fields associated with SRs and SBRT treatments.