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目的:探讨多物质伪影降低（MMAR）技术对口腔金属植入物患者颌面部CT图像的影响。方法:回顾性收集2019年3月至2020年2月郑州大学第一附属医院放射科用宽体探测器 CT行颌面部扫描且含有金属义齿植入的30例患者资料，患者病变部位均受到金属植入物伪影影响，行能谱扫描后采用静脉期分别重建 120 kV-like、虚拟单能量成像（VMI）（70、90、110 keV）、VMI（70、90、110 keV）+MMAR（简称VMI+M）图像，共 7 个图像序列。测量同层面病变及头长肌CT值和噪声（SD），计算病变伪影指数（AI）。通过 Friedman检验及 Wilcoxon检验实现对图像质量的客观、主观评估。结果:7组图像SD、AI间差异有统计学意义（SD：n χ2=133.800，n P<0.001；AI：n χ2=92.147，n P<0.001），VMI 110 keV+M图像SD［10（8， 12）］、AI［6（5， 9）］为7组内最低，其AI值与VMI 90 keV+M图像相比差异无统计学意义（n P=0.271）。VMI+M组SD、AI值低于对应单能量水平VMI组（均n P<0.05）。7组图像主观评分间差异有统计学意义（n χ2=151.199，n P<0.001）。VMI（70、90、110 keV）+M图像评分高于对应单能量水平VMI图像（n Z=-4.583，n P=0.000；n Z=-3.742，n P=0.000；n Z=-2.449，n P=0.014）。VMI 90 keV+M图像主观评分［4（3， 4）］最高，高于其余6组（均n P<0.05）。30例中有26例病变区域伪影完全消除，对比度良好，病变显示清晰，图像效果最佳。n 结论:宽体探测器CT的MMAR技术去除口腔金属植入体伪影效果明显，能提高图像质量，VMI 90 keV+MMAR图像能兼顾最佳伪影去除效果及良好的组织对比。“,”Objective:To investigate the effect of multi-material artifact reduction (MMAR) technique on the maxillofacial CT images of patients with metallic dental implants.Methods:The data of 30 patients with metal denture implants who underwent maxillofacial wide-detector CT scans in the Department of Radiology of the First Affiliated Hospital of Zhengzhou University from March 2019 to February 2020 were retrospectively collected. The images of the lesion sites of patients were all affected by the metal implants artifacts. The 120 kV-like, virtual monoenergetic images (VMI) (70, 90, 110 keV), VMI (70, 90, 110 keV)+MMAR images were reconstructed at venous phase by energy spectrum scanning. A total of 7 image sequences were obtained for each patient. The CT value and noise value of the lesion and the longus capitis muscle on the same plane were measured, and the artifact index (AI) of lesion was calculated.Friedman test and Wilcoxon test were used to evaluate image quality objectively and subjectively.Results:There were significant differences in SD and AI among the 7 groups (n χn 2=133.800,n P<0.001;n χn 2=92.147,n P<0.001). The SD[10 (8, 12)] and AI [6 (5, 9)]of VMI 110 keV+M images were the lowest, but there were no significant differences in AI between VMI 110 keV+M and VMI 90 keV+M image (n P= 0.271). The SD and AI of VMI+M group were lower than those in VMI group (all n P<0.05). There was significant difference in image score among the 7 groups (n χ n 2 = 151.199, n P<0.001). The image scores of VMI (70, 90, 110 keV)+M group were higher than those of VMI group (n Z=-4.583, n P = 0.000; n Z=-3.742, n P = 0.000; n Z =-2.449, n P = 0.014). The subjective score of VMI 90 keV+M [4 (3, 4)] was the highest, higher than those of other 6 groups (all n P<0.05), in 26 out of 30 cases, lesions displayed clear contrast, and the artifacts eliminated completely.n Conclusion:The MMAR technique of wide-detector CT might effectively remove the metallic dental implants artifacts and improve the image quality. VMI 90 keV+MMAR images could achieve the best artifact removal effect and good tissue contrast.