Abstract:
Multi-energy computed tomography (MECT) offers the opportunity for advanced visualization, detection, and quantification of select elements (e.g., iodine) or materials (e.g., fat) beyond the capability of standard single-energy computed tomography (CT). However, the use of MECT requires careful consideration as substantially different hardware and software approaches have been used by manufacturers, including different sets of user-selected or hidden parameters that affect the performance and radiation dose of MECT. Another important consideration when designing MECT protocols is appreciation of the specific tasks being performed; for instance, differentiating between two different materials or quantifying a specific element. For a given task, it is imperative to consider both the radiation dose and task-specific image quality requirements. Development of a quality control (QC) program is essential to ensure the accuracy and reproducibility of these MECT applications. Although standard QC procedures have been well established for conventional single-energy CT, the substantial differences between single-energy CT and MECT in terms of system implementations, imaging protocols, and clinical tasks warrant QC tests specific to MECT. This task group was therefore charged with developing a systematic QC program designed to meet the needs of MECT applications. In this report, we review the various MECT approaches that are commercially available, including information about hardware implementation, MECT image types, image reconstruction, and postprocessing techniques that are unique to MECT. We address the requirements for MECT phantoms, review representative commercial MECT phantoms, and offer guidance regarding homemade MECT phantoms. We discuss the development of MECT protocols, which must be designed carefully with proper consideration of MECT technology, imaging task, and radiation dose. We then outline specific recommended QC tests in terms of general image quality, radiation dose, differentiation and quantification tasks, and diagnostic and therapeutic applications.
摘要:
多能量计算机断层扫描(MECT)为高级可视化提供了机会,检测,和选定元素的量化(例如,碘)或材料(例如,脂肪)超出了标准单能量计算机断层扫描(CT)的能力。然而,MECT的使用需要仔细考虑,因为制造商已经使用了完全不同的硬件和软件方法,包括影响MECT性能和辐射剂量的不同用户选择或隐藏参数集。设计MECT协议时的另一个重要考虑因素是对正在执行的特定任务的理解;例如,区分两种不同的材料或量化特定元素。对于给定的任务,必须同时考虑辐射剂量和特定任务的图像质量要求。开发质量控制(QC)程序对于确保这些MECT应用的准确性和可重复性至关重要。尽管常规单能量CT已经建立了标准的QC程序,单能量CT和MECT在系统实施方面的实质性差异,成像协议,和临床任务需要特定于MECT的QC测试。因此,该任务组负责开发旨在满足MECT应用需求的系统QC程序。在这份报告中,我们回顾了商业上可用的各种MECT方法,包括有关硬件实施的信息,MECT图像类型,图像重建,以及MECT独有的后处理技术。我们满足了MECT幻影的要求,回顾代表性的商业MECT幻影,并提供有关自制MECT幻影的指导。我们讨论了MECT协议的发展,必须仔细设计,并适当考虑MECT技术,成像任务,和辐射剂量。然后,我们根据一般图像质量概述了具体的推荐QC测试,辐射剂量,区分和量化任务,以及诊断和治疗应用。