Zhao Jie, Cheng Qiang, Liu Chuan, Wang Qiqi, Lv Yuchan, Tang Ziyi, Luo Yuxi, Yang Haitao
Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, 1 Youyi Road, Yuzhong District, Chongqing, 400016, China.
Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
Insights Imaging. 2023 Oct 26;14(1):181. doi: 10.1186/s13244-023-01533-3.
To investigate the optimal parameters of spectral CT for preferably visualizing the periprosthetic vasculature and metal artifact reduction (MAR) in total hip arthroplasty (THA).
A total of 34 THA of 30 patients were retrospectively included. Image reconstructions included conventional image (CI), CI combined with MAR (CI), and virtual monoenergetic images (VMI) combined with MAR (VMI) at 50-120 keV. The attenuation and standard deviation of the vessel and artifact, and the width of artifact were measured. Qualitative scoring was evaluated including the vascular contour, the extent of artifact, and overall diagnostic evaluation.
The attenuation, noise of the vessel and artifact, and the width of artifact decreased as the energy level increased (p < 0.001). The downtrend was relatively flat at 80-120 keV, and the vascular attenuation dropped to 200 HU at 90 keV. The qualitative rating of vascular contour was significantly higher at CI (3.47) and VMI 60-80 keV (2.82-3.65) compared with CI (2.03) (p ≤ 0.029), and the highest score occurred at 70 and 80 keV (3.65 and 3.56). The score of the extent of artifact was higher at VMI 80 keV than CI (3.53 VS 3.12, p = 0.003). The score of the overall diagnostic evaluation was higher at VMI 70 and 80 keV (3.32 and 3.53, respectively) than CI (3.12) (p ≤ 0.035).
Eighty kiloelectron volts on VMI, providing satisfactorily reduced metal artifacts and improved vascular visualization, can be an optimal recommended parameter of spectrum CT for the assessment of periprosthetic vasculature in THA patients.
The metal artifact is gradually reducing with increasing energy level; however, the vascular visualization is worsening. The vascular visualization is terrible above 100 keV, while the vessel is disturbed by artifacts below 70 keV. The best performance is found at 80 keV.
• VMI can provide both reduced metal artifacts and improved vascular visualization. • Eighty kiloelectron volts on VMI performs best in vascular visualization of total hip arthroplasty patients. • Energy spectrum CT is recommended for routine use in patients with total hip arthroplasty.
研究光谱CT的最佳参数，以便在全髋关节置换术（THA）中更好地显示假体周围血管并减少金属伪影（MAR）。
回顾性纳入30例患者的34例THA。图像重建包括常规图像（CI）、CI联合MAR（CI）以及50 - 120 keV的虚拟单能量图像（VMI）联合MAR（VMI）。测量血管和伪影的衰减、标准差以及伪影宽度。进行定性评分评估，包括血管轮廓、伪影范围和整体诊断评估。
随着能量水平升高，血管和伪影的衰减、噪声以及伪影宽度均降低（p < 0.001）。在80 - 120 keV时下降趋势相对平缓，90 keV时血管衰减降至200 HU。与CI（2.03）相比，CI（3.47）和60 - 80 keV的VMI（2.82 - 3.65）的血管轮廓定性评分显著更高（p≤0.029），最高评分出现在70和80 keV（3.65和3.56）。80 keV的VMI的伪影范围评分高于CI（3.53对3.12，p = 0.003）。70和80 keV的VMI的整体诊断评估评分高于CI（分别为3.32和3.53）（p≤0.035）。
VMI上的80千电子伏特能提供令人满意的金属伪影减少和血管可视化改善，可作为光谱CT评估THA患者假体周围血管的最佳推荐参数。
金属伪影随着能量水平升高逐渐减少；然而，血管可视化却变差。100 keV以上血管可视化很差，而70 keV以下血管受伪影干扰。在80 keV时性能最佳。
• VMI既能减少金属伪影又能改善血管可视化。• VMI上的80千电子伏特在全髋关节置换术患者的血管可视化方面表现最佳。• 推荐对全髋关节置换术患者常规使用能谱CT。
