Department of the Imaging, University Hospital Pilsen, Alej Svobody 80, 323 00, Pilsen, Czechia.
Department of the Imaging, University Hospital Pilsen, Alej Svobody 80, 323 00, Pilsen, Czechia.
Eur J Radiol. 2021 Apr;137:109614. doi: 10.1016/j.ejrad.2021.109614. Epub 2021 Feb 24.
to assess the feasibility of CT with an integrated photon-counting-detector system (PC-CT) in the body imaging of clinical patients.
120 examinations using photon counting detector CT were evaluated in six groups: 1/ a standard-dose lung, 2/ low-dose lung, 3/ ultra-high resolution (UHR) lung, 4/ standard-dose abdominal, 5/ lower-dose abdominal, 6/ UHR abdominal CTA. All CT examinations were performed on a single-source prototype device equipped with a photon counting detector covering a 50 cm scan field of view. Standard dose examinations were performed with the use of detector element size of 0.4 mm, ultra-high-resolution examinations with the detector element size of 0.2 mm, respectively. The stability of the system during imaging was tested. The diagnostic quality of the acquired images was assessed based on the imaging of key structures and the noise level in five-point scale, the effective dose equivalent, dose length product and noise level, and also relation to body mass index and body surface area were compared with three similar groups of CT images made with energy integrating high end scanner. The parameters were evaluated using Wilcoxon test for independent samples, the independence was tested using Kruskal-Wallis test.
When PC-CT images radiation dose is compared with the similar imaging using energy integrating CT, the PC-CT shows lower dose in ultra-high resolution mode, the dose is significantly lower (p < 0.0001), the standard dose examinations were performed with the comparable radiation doses. PC-CT exhibited the significantly higher ratio between parenchyma signal and background noise both in lung and in abdominal imaging (p < 0.0001).
PC-CT showed imaging stability and excellent diagnostic quality at dose values that are comparable or better to the quality of energy integrating CT, the better signal and improved resolution is most important advantage of photon counting detector CT over energy integrating detector CT.
评估集成光子计数探测器系统（PC-CT）在临床患者体部成像中的可行性。
对使用光子计数探测器 CT 进行的 120 次检查进行了评估，共分为 6 组：1/ 标准剂量肺部检查、2/ 低剂量肺部检查、3/ 超高分辨率（UHR）肺部检查、4/ 标准剂量腹部检查、5/ 低剂量腹部检查、6/ UHR 腹部 CTA。所有 CT 检查均在配备光子计数探测器的单源原型设备上进行，探测器覆盖 50cm 扫描视野。标准剂量检查使用探测器元件尺寸为 0.4mm，超高分辨率检查使用探测器元件尺寸为 0.2mm。测试了成像过程中系统的稳定性。根据关键结构的成像和五点噪声水平评估采集图像的诊断质量，还比较了等效有效剂量、剂量长度乘积和噪声水平，并与使用能量积分高端扫描仪进行的三组类似 CT 图像进行了比较。使用 Wilcoxon 检验独立样本对参数进行评估，使用 Kruskal-Wallis 检验检验独立性。
当将 PC-CT 图像的辐射剂量与使用能量积分 CT 进行的类似成像进行比较时，PC-CT 在超高分辨率模式下显示出较低的剂量，剂量显著降低（p < 0.0001），标准剂量检查的辐射剂量相当。PC-CT 显示在肺部和腹部成像中，组织信号与背景噪声之间的比值明显更高（p < 0.0001）。
PC-CT 在与能量积分 CT 质量相当或更好的剂量值下显示出成像稳定性和出色的诊断质量，光子计数探测器 CT 相对于能量积分探测器 CT 的最重要优势是更好的信号和提高的分辨率。
