Translational Development of Photon-Counting CT Imaging

自2015年以来，研究性光子计数CT扫描仪一直安装在NIH临床中心的放射和成像科学部。在过去的5年里，研究小组对光子计数和常规图像的临床质量进行了比较，在标准的临床成像应用中，如腹盆腔增强CT、低剂量肺部筛查CT、腹部和头部和颈部的计算机断层血管成像(CTA)和脑CT，未能发现这些技术之间的任何差异。 2018年，研究团队改变了成员身份，并与杜克大学医学物理系合作，将重点重新转向基于临床任务的扫描仪性能医学物理评估。这些基于任务的评估，包括比较通常在腹部的软组织测量，探索降低到极低辐射剂量成像的影响，血管成像，以及评估应用于肺和骨骼成像的更高分辨率能力。临床成像任务的一个例子是优化冠状动脉的血管成像。在这项研究中，该团队与NHLBI的科学家合作，表征了光子计数的能力，以区分冠状动脉模体中高密度碘化造影剂和邻近的钙离子。 研究团队目前专注于三个领域：针对特定临床任务优化扫描仪采集和后处理参数；将光子计数CT和后处理技术用于肾脏病变的可视化和表征；以及利用多能量(光谱)成像能力。这些能力可以用来成像创新的造影剂，如铋。

The investigational Photon-Counting CT scanner has been installed in the Radiology and Imaging Sciences Department at NIH Clinical Center since 2015. Over the last 5 years, the research team conducted comparisons of the clinical quality of the Photon-counting vs conventional images and was not able to detect any difference between these techniques in standard clinical imaging applications such as abdominal pelvic contrast enhanced CT, low dose lung screening CT, computed tomographic angiography (CTA) of the abdomen and head and neck, and cerebral CT. In 2018 the research team changed in membership and redirected focus toward clinical task-based medical physics assessments of scanner performance in collaboration with Duke University Medical Physics Department. These task based assessments, include comparison of soft tissue measures of comparison typically in the abdomen, explorations of impact of lowering to very low radiation dose imaging, vascular imaging and evaluation of higher resolution capabilities applied to imaging of the lung and bone. An example of clinical imaging tasks is the optimization of vascular imaging of coronary arteries. In this study the team collaborated with scientists from NHLBI to characterize the capabilities of photon counting to distinguish between high density iodinated contrast and adjacent calcium in coronary artery phantoms. The research team is currently focused on three areas: optimization of scanner acquisition and post-processing parameters for specific clinical tasks, utility of photon-counting CT and post-processing techniques for the visualization and characterization of kidney lesions, and leveraging multi-energy (spectral) imaging capabilities. These capabilities may be used to image innovative contrast agents such as Bismuth.