A Novel System for Reducing Radiation Dose of CT Perfusion

项目概要/摘要 X射线计算机断层扫描（CT）已越来越多地用于医疗诊断，目前已达到更多 在美国每年有超过8000万次CT扫描。CT的使用越来越多， 对病人的辐射剂量。据估计，每2000次CT扫描将导致一种未来的癌症，即， 每年从8000万次CT扫描中发现40,000例未来癌症。CT脑灌注（CTP）是一种广泛使用的 影像学技术用于评价中风和脑血管疾病的血流动力学变化。 然而，CTP涉及患者的高辐射剂量，因为CTP扫描重复约40次 在相同的解剖位置，以便捕获造影剂团的完全通过。这是 这是FDA关注的一个主要问题，特别是当对同一个组织进行多次连续CTP时， 患者，例如监测再通后的再灌注。有几种技术已经应用于辐射 CTP扫描中的剂量降低，包括管电流和管电压的降低，以及使用新的 降噪技术，如迭代重建（IR）。然而，由此产生的辐射剂量 现有的CTP扫描仍然显著高于标准头部CT扫描。IR的应用 CTP中的技术是非常有限的，由于高复杂性和计算负担，用于处理多个 可能影响临床工作流程的CTP图像。目前STTR项目的首要目标是开发 并将一种新型CT成像平台商业化，该平台通过以下方式降低现有CTP技术的辐射剂量： ~75%，而不影响成像速度或质量。这项专利技术减少了辐射剂量 通过控制X射线源在预先指定的时间间隔（而不是连续）打开， 旋转角度（即，编程脉冲X射线）。然后可以重建动态CTP图像系列 使用保持高空间和时间分辨率以及与 标准的CTP扫描。在拟议的第1阶段项目中，我们计划展示概念验证 通过进一步开发、优化和评估图像重建算法， 体模和临床CTP数据。我们还将与CT供应商合作，以确保 技术有一条实现商业化的现实途径。

Project Summary/Abstract X-ray computed tomography (CT) has been increasingly used in medical diagnosis, currently reaching more than 80 million CT scans every year in the US. The increasing use of CT has sparked concern over the effects of radiation dose on patients. It is estimated that every 2000 CT scans will cause one future cancer, i.e., 40,000 cases of future cancers from 80 million CT scans every year. CT brain perfusion (CTP) is a widely used imaging technique for the evaluation of hemodynamic changes in stroke and cerebrovascular disorders. However, CTP involves high radiation dose for patients as the CTP scan is repeated on the order of 40 times at the same anatomical location, in order to capture the full passage of the contrast bolus. This has been raised as a major concern by the FDA, especially when multiple successive CTPs are performed on the same patient, e.g. to monitor reperfusion following recanalization. Several techniques have been applied for radiation dose reduction in CTP scans, including reduction of tube current and tube voltage, as well as the use of novel noise reduction techniques such as iterative reconstruction (IR). However, the resultant radiation dose of existing CTP scans is still significantly higher than that of a standard head CT scan. The application of IR techniques in CTP is very limited due to the high complexity and computational burden for processing multiple CTP images that may impair clinical workflow. The overarching goal of the present STTR project is to develop and commercialize a novel CT imaging platform that reduces the radiation dose of existing CTP techniques by ~75% without compromising imaging speed or quality. This proprietary technology reduces the radiation dose of CTP scans by controlling the X-ray source to be on intermittently (instead of continuously) at pre-specified rotation angles (i.e., programmed pulsed X-ray). The dynamic CTP image series can then be reconstructed using algorithms that preserve high spatial and temporal resolutions as well as image quality comparable to those of standard CTP scans. During the proposed Phase 1 project, we plan to demonstrate a proof-of-concept of our technology by further developing, optimizing and evaluating the image reconstruction algorithm using both phantom and clinical CTP data. We will also collaborate with CT vendors to ensure the developed technology has a realistic pathway to commercialization.