能谱CT联合MAR技术在去除腰椎椎弓根内固定金属伪影中的应用价值

Application Value of Energy Spectrum CT Combined with MAR in Removing Metal Artifacts of Lumbar Pedicle Internal Fixation

目的:分析能谱CT成像联合多伪影去除(MAR)技术在去除腰椎椎弓根术后金属伪影中的应用价值。方法:回顾性收集我院2020年2月-2021年2月期间行腰椎椎弓根螺钉内固定术后CT复查患者75例,其中行常规CT平扫患者28例为对照组(非MAR组),行能谱CT平扫联合MAR技术患者47例为实验组(MAR组)。比较MAR组和非MAR组图像在伪影最重层面上椎管内、椎体上、椎旁软组织、棘突旁和远端脂肪的CT值、伪影指数(AI);同时对两组图像进行重建,包括容积再现(VR)及多平面重建(MPR),由2位高年资医师对原始图像及重建图像进行主观评价后打分并进行比较。结果:MAR组图像在伪影最重层面上椎管内、椎体上、椎旁软组织和远端脂肪的伪影指数较非MAR组减低,差异有统计学意义(P<0.05);能谱CT联合MAR技术图像主观评分较非MAR组增高,差异有统计学意义(P<0.05)。结论:能谱CT联合MAR技术去除腰椎椎弓根内固定金属伪影效果较常规CT扫描明显提升,且CT值更接近正常组织CT值。

Objective:To analyze the application value of energy spectrum CT imaging combined with multiple artifact removal(MAR)in the removal of metal artifacts after lumbar pedicle surgery.Methods:A total of 75 patients with CT review after lumbar pedicle screw internal fixation were retrospectively collected in our hospital from February 2020 to February 2021.Among them,28 patients who received conventional CT plain scan were the control group(non-MAR group).Forty-seven patients receiving energy spectrum CT plain scan combined with MAR were treated as the experimental group(MAR group).CT values and artifact index(AI)of images in the spinal canal,supraspinal body,paravertebral soft tissue,paraspinous process and distal fat were compared between the MAR group and the non-MAR group at the heaviest artifact levels.At the same time,the two groups of images were reconstructed including volume rendering(VR)and multi-planar reformation(MPR).The original images and reconstructed images were evaluated subjectively by two senior physicians and then scored and compared.Results:The artifact index in spinal canal,supraspinal body,paraspinal soft tissue and distal fat in MAR group was lower than that in non-MAR group,with statistical significance(P<0.05).The subjective score of energy spectrum CT combined with MAR was higher than that of non-MAR group,and the difference was statistically significant(P<0.05).Conclusion:The effect of energy spectrum CT combined with MAR in removing metal artifacts of lumbar pedicle internal fixation is significantly better than that of conventional CT scan,and the CT value is closer to that of normal tissue.