Duke University, 2424 Erwin Rd, Durham, NC, 27710, USA.
Henry Ford Health System, 2799 W Grand Blvd, Detroit, MI, 48202, USA.
Med Phys. 2019 Nov;46(11):e735-e756. doi: 10.1002/mp.13763. Epub 2019 Sep 11.
The rapid development and complexity of new x-ray computed tomography (CT) technologies and the need for evidence-based optimization of image quality with respect to radiation and contrast media dose call for an updated approach towards CT performance evaluation.
This report offers updated testing guidelines for testing CT systems with an enhanced focus on the operational performance including iterative reconstructions and automatic exposure control (AEC) techniques.
The report was developed based on a comprehensive review of best methods and practices in the scientific literature. The detailed methods include the assessment of 1) CT noise (magnitude, texture, nonuniformity, inhomogeneity), 2) resolution (task transfer function under varying conditions and its scalar reflections), 3) task-based performance (detectability, estimability), and 4) AEC performance (spatial, noise, and mA concordance of attenuation and exposure modulation). The methods include varying reconstruction and tube current modulation conditions, standardized testing protocols, and standardized quantities and metrology to facilitate tracking, benchmarking, and quantitative comparisons.
The methods, implemented in cited publications, are robust to provide a representative reflection of CT system performance as used operationally in a clinical facility. The methods include recommendations for phantoms and phantom image analysis.
In line with the current professional trajectory of the field toward quantitation and operational engagement, the stated methods offer quantitation that is more predictive of clinical performance than specification-based approaches. They can pave the way to approach performance testing of new CT systems not only in terms of acceptance testing (i.e., verifying a device meets predefined specifications), but also system commissioning (i.e., determining how the system can be used most effectively in clinical practice).
We offer a set of common testing procedures that can be utilized towards the optimal clinical utilization of CT imaging devices, benchmarking across varying systems and times, and a basis to develop future performance-based criteria for CT imaging.
新的 X 射线计算机断层扫描（CT）技术的快速发展和复杂性，以及基于证据的优化图像质量对辐射和对比剂剂量的需求，都需要对 CT 性能评估方法进行更新。
本报告提供了用于测试 CT 系统的更新测试指南，重点关注包括迭代重建和自动曝光控制（AEC）技术在内的操作性能。
该报告是基于对科学文献中最佳方法和实践的综合回顾而制定的。详细方法包括评估 1）CT 噪声（幅度、纹理、不均匀性、非均匀性）、2）分辨率（任务转移函数在不同条件下及其标量反射）、3）基于任务的性能（可检测性、可估计性）和 4）AEC 性能（空间、噪声和 mA 衰减和曝光调制的一致性）。方法包括改变重建和管电流调制条件、标准化测试协议以及标准化的量和计量学，以方便跟踪、基准测试和定量比较。
在引用的出版物中实施的方法，对于提供 CT 系统性能的代表性反映是稳健的，这些性能是在临床设施中实际操作情况下使用的。该方法包括对体模和体模图像分析的建议。
与该领域当前向定量和操作参与的专业轨迹一致，所提出的方法提供了比基于规范的方法更能预测临床性能的定量。它们可以为新 CT 系统的性能测试铺平道路，不仅可以进行验收测试（即验证设备是否符合预定义的规范），还可以进行系统调试（即确定系统在临床实践中如何最有效地使用）。
我们提供了一组通用的测试程序，可用于优化 CT 成像设备的临床应用，跨不同系统和时间进行基准测试，并为开发基于性能的 CT 成像标准提供基础。
