Periodic Contrast-Enhanced CT With HYPR Reconstruction For Ablation Monitoring

描述(由申请人提供)：监测消融生长和确定治疗效果已成为热瘤消融面临的最重大挑战之一。消融后成像无法在消融发展过程中监测消融，并且当前的实时策略不能提供足够的消融区域的空间分辨率。如果没有监测消融生长的手段，就没有办法在意外热损伤发生之前防止它，也不可能在最有效的时间改变治疗过程。在这项应用中，我们将开始开发、优化和验证一种新的治疗监测技术，该技术使用大多数扫描仪上已有的技术，使用定期对比增强计算机断层扫描(CECT)。定期CECT将允许在治疗过程中的几个时间点进行监测，同时将患者的总对比负荷降至最低。具体来说，我们建议：1.测量热消融过程中造影剂的摄取和转运。在这里，我们将测量消融过程中造影剂在正常肝和肾脏以及两种肿瘤模型中的滞留或排出。2.优化应用周期性CECT进行消融监测的造影剂和图像采集参数。为此，我们将在热消融过程中对周期性CECT进行表征，并使用单纯形法优化扫描时间、辐射剂量和造影剂注入量。3.自动执行HYPR处理，以便定期进行CECT消融监测。这一目标将侧重于开发涂抹器发现、块匹配和配准算法，以促进在每个成像序列期间自动进行HYPR处理。4.将周期性CECT技术与组织病理学和标准CECT进行比较。通过比较正常肝、肾和两种肿瘤模型的影像表现和组织病理学，验证周期性CECT技术的有效性。

DESCRIPTION (provided by applicant): Monitoring ablation growth and determining treatment efficacy has become one of the most significant challenges facing thermal tumor ablation. Post-ablation imaging provides no way to monitor the ablation as it develops and current real time strategies fail to provide sufficient spatial resolution of the ablation zone. Without a means to monitor ablation growth, there is no way to prevent unintended thermal damage before it occurs, nor is it possible to alter the course of treatment at the most effective times. In this application, we will begin to develop, optimize and validate a new treatment monitoring technique using technology already available on most scanners using periodic contrast-enhanced computed- tomography (CECT). Periodic CECT will allow monitoring at several time points during the course of treatment while minimizing the total contrast load to the patient. Specifically, we propose to: 1. Measure the uptake and transport of contrast media during thermal ablation Here we will measure the retention or expulsion of contrast media in normal liver and kidney, and two tumor models during ablation. 2. Optimize administration of contrast media and image acquisition parameters for ablation monitoring with periodic CECT In this aim we will characterize periodic CECT during thermal ablation and optimize scan timing, radiation dose and contrast infusion rate using simplex methods. 3. Automate HYPR processing for periodic CECT ablation monitoring. This aim will focus on developing applicator discovery, block matching and registration algorithms to facilitate automated HYPR processing during each imaging sequence. 4. Validate the periodic CECT technique with histopathology and standard CECT In this aim the validity of periodic CECT will be verified by comparing the imaging appearance and histopathology of ablations created in normal liver and kidney, and two tumor models.