影像科学与光化学 ›› 2023, Vol. 41 ›› Issue (6): 332-337.DOI: 10.7517/issn.1674-0475.230809

• 综述与论文 • 上一篇    下一篇

全踝关节置换术后CT复查中MAC技术去金属伪影的临床应用

邹萌1, 李真林2, 潘雪琳2, 樊敏2   

  1. 1. 四川大学华西医院上锦医院放射科, 四川 成都 610041;
    2. 四川大学华西医院放射科, 四川 成都 610041
  • 收稿日期:2023-08-18 出版日期:2023-11-23 发布日期:2023-12-14
  • 通讯作者: 李真林

Application of MAC Technique in CT Removal of Metal Artifacts after Total Ankle Arthroplasty

ZOU Meng1, LI Zhenlin2, PAN Xuelin2, FAN Min2   

  1. 1. Department of Radiology, Shangjin Hospital, West China Hospital, Sichuan University, Chengdu 610041, Sichuan, P. R. China;
    2. Department of Radiology, West China Hospital, Sichuan University, Chengdu 610041, Sichuan, P. R. China
  • Received:2023-08-18 Online:2023-11-23 Published:2023-12-14

摘要: 探讨全踝关节置换术后,金属伪影校正(MAC)技术减少CT金属伪影的临床应用价值。回顾性收集进行全踝关节置换术后行CT复查的患者40例,将原始数据经过MAC技术和KARL-3D迭代重建技术重建后分为A、B两组,A组为MAC技术重建,B组为KARL-3D迭代重建。在A、B两组中选取相同两个层面(胫骨端假体层面、距骨端假体层面)勾画感兴趣区(ROI),测量其CT值和图像噪声,计算其平均值,并以肌肉为参考计算信噪比(SNR)和对比噪声比(CNR)。由2位放射科医师通过盲法对A、B两组图像进行主观评分。结果显示,A组与B组相比,A组金属高密度区、假体旁关节间隙及假体旁骨组织的CT值减少,金属低密度区CT值增加,图像噪声值A组均小于B组,差异均有统计学意义(P<0.05)。SNR、CNR及图像评分A组均高于B组,差异均有统计学意义(P<0.05)。MAC重建技术能减少全踝关节置换术后CT检查中的金属伪影,提升图像质量,具有较好的临床应用价值。

关键词: 去金属伪影, 全踝关节置换术, CT扫描, 重建算法

Abstract: To investigate the clinical application value of metal artifact correction (MAC) to reduce metal artifact in CT after total ankle arthroplasty. 40 patients who underwent CT reexamination after total ankle arthroplasty were retrospectively collected. The original data were reconstructed by MAC technique and KARL-3D iterative reconstruction and divided into two groups, group A was reconstructed by MAC technique and group B was reconstructed by KARL-3D iterative reconstruction. In group A and group B, the same two layers (tibial prosthesis and talus prosthesis) were selected to characterize the region of interest (ROI), measured the CT value and image noise, calculated the mean value, and calculated the signal-to-noise ratio (SNR) and contrastive noise ratio (CNR) using muscle as reference. Group A and group B were scored subjectively by two radiologists through blind method. The results show that, compared with group B, the CT values of the metal high density area, joint space beside prosthesis and bone tissue in group A were reduced, while the CT values of the metal low density area were increased. The image noise values in group A were all lower than those in group B, with statistical significance (P<0.05). SNR, CNR and image score of group A were higher than those of group B, with statistical significance (P<0.05). MAC reconstruction technique can reduce metal artifacts in CT examination after total ankle joint replacement, improve image quality, and has good clinical application value.

Key words: demetallizing artifact, total ankle arthroplasty, CT scan, algorithm