摘要
目的探讨去金属伪影(MAC)技术在骨科金属植入物术后CT检查中的应用价值。方法收集2014年11月—2015年9月间40例在行骨科金属植入物术后接受16排CT扫描检查的患者资料,对其同一扫描的原始数据,分别采用设备自带的标准滤波反投影重建算法(常规重建组)和MAC技术的去金属伪影重建法(MAC重建组)进行图像后处理。由3名有经验的放射科医师采用双盲法对两组图像质量进行客观、主观评价,客观评价指标包括图像噪声值(SD)、信噪比(SNR)、对比噪声比(CNR),主观评价采用5分赋值法。结果 MAC重建组CT图像的SNR、CNR均显著大于常规重建组(P值均<0.01),金属植入物相邻肌肉的噪声值(SD1)、相同测量层面皮下脂肪的噪声值(SD2)均显著小于常规重建组(P值均<0.01)。MAC重建组的主观评价评分为(4.37±0.20)分,显著高于常规重建组的(2.45±0.15)分(P<0.01)。3名放射科医师CT图像质量主观评价的一致性良好(Kappa值=0.89)。与常规重建组多平面重建(MRR)模式的冠状位CT图像和容积再现(VR)模式重建图像相比,MAC重建组图像的伪影对周围组织的干扰明显减小,能够清晰地观察金属植入物周围的骨质、软组织情况,图像噪声明显降低。结论 MAC技术能显著消除金属伪影,提高金属植入物受检部位CT图像的质量,且周围软组织清晰可见,该技术对骨科金属植入物术后CT图像分析具有良好的临床应用价值。
Objective To evaluate the value of metal artifact correction （MAC）TM in clinical application of metal artifact reduction in CT after orthopedic operation. Methods CT images of 40 patients with metal implant after orthopedic operation were off-line post-processed with conventional reconstruction （group A） and MAC reconstruction （group B）. Signal noise （SD）, signal-to-noise ratio （SNR） and contrast-to-noise ratio （CNR） of images were evaluated objectively and compared between two groups. Meanwhile, the images were subjectively evaluated with 5-point method by three experienced radiologists. Results The SNR and CNR in group B were significantly increased compared to those in group A （both P〈0.01 ）. The noise of neighboring muscles （SDI） and the noise of subcutaneous fat （SD2） of CT images in group B were significantly reduced compared to those in group A （both P〈0.01）. The subjective score of CT images in group B was significantly higher than that in group A （4.37±0.20 vs. 2.45± 0.15, P〈0.01 ）. Three radiologists showed a consistency in image evaluation for both groups （Kappa=0.89）. Compared with coronal images and VR images in group A, there was less interference from artifacts for the surrounding tissue, the bone and soft tissue surrounding the implant could be clearly observed, and the SD of images was significantly decreased in group B. Conclusion The post processing technique of MACTM can significantly reduce metal artifacts of CT images with metal implant and can display better details around metal clearly. （Shanghai Med J, 2017, 40= 165-168）
出处
《上海医学》
北大核心
2017年第3期165-168,共4页
Shanghai Medical Journal
关键词
去金属伪影技术
计算机断层扫描
图像质量
评价
Metal artifact correction technology
Computed tomography
Image quality
Evaluation
