The application of monoenergetic technology of dual-source CT in removing the artifact of metal fixation after the operation of lumbar spondylolysis / 实用放射学杂志

ABSTRACT

Objective To explore the clinical value of monoenergetic technology of dual-source CT in removing the artifact of me-tallic fixation after the operation of lumbar spondylolysis.Methods 24 cases of patients with metallic fixation after operation of lum-bar spondylolysis were scanned by dual-energy CT.To reconstruct the imaging using monoenergetic and 3D Inspace software,obtain 50,80,110,140,170 keV five groups of images and the multi-planar reconstruction*(MPR),volume vendering(VR),maximum intensity projection(MIP)imaging in different conditions.The five groups image and average weighted 120kev image are evaluate by two senior radiologist.The quality score of five groups of images and the average weighted images are analyzed statistically using Kruskal-Wallis test.The clinical value of images in the optimal condition are evaluated by two senior department of orthopedics phy-sicians.The results of two radiologists and department of orthopedics physician are examined by kappa test to evaluate consistency. Results In all patients after operation,the case of 110keV images above 3 points is 24,the case of 80keV images above 3 points is 14,the case of of 140keV images above 3 points is 13,the case of weighted average 120kev images above 3 points is 8.Images in 110keV have the best quality (F=98.523,P<0.01).MPR,VR,MIP images are reconstructed in 110keV.The ratio of image which are excellent and have high clinical value is 86.1%,especially the ratio of MPR image is 100%.Conclusion Monoenergetic technology of dual-source CT has a higher clinical value in removing the artifact of metallic fixation after the operation of lumbar spondylolysis.Under the condition of 110keV the quality of images are best,the reconstructed images using MPR Technology have the best clinical value.