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Objective: To compare the CT artifacts reduction by using of orthopedic metal artifact reduction (OMAR, Philips Healthcare) technique and high tube voltage approach in patients after pedicle screw placement. Methods: 64 patients after pedicle screw placement who were randomly assigned into 2 groups (Group A and Group B, 32 for each) underwent CT scans on a 64-slice scanner. The scan protocol were 120kVp/100mAs for group A, and 140kVp/100mAs for group B. Image data were reconstructed with iterative reconstruction technique (IRT) only and IRT plus OMAR in group A, and with IRT only in group B. 3 series of images were acquired: A1 (120kVp with IRT only), A2 (120kVp with IRT plus OMAR), and B1 (140kVp with IRT only). Image noise and CT attenuation of spinal canal and muscle nearby were measured at the screw level. The volume of hypo- and hyper- intensity artifacts caused by pedicle screw were measured using a threshold method in all series. Subjective image quality assessment was performed by 2 independent readers according to the features of artifacts range, clearance of intermuscular space and bony trabecula, image distortion and overall diagnostic confidence by using a 4-point scale. ANOVA and Friedman test were used for comparison of image quality among 3 series. Result: The effective dose was increased 48.1% of group B than group A for using high tube voltage protocol. Image noise was significantly increased in A2 images compared to A1 and B1 images (13.0HU±4.5, vs. 11.0HU±2.4, 10.6HU±2.7, p=0.010). There was no significant difference in CT attenuation of spinal canal among images (A1, A2, B1: 37.8HU±14.3, 47.1HU±21.3, 45.1HU±17.7, p=0.097). CT attenuation of muscle in A2 images was significantly lower compared to A1 and B1 images (52.1HU±15.9 vs. 60.3HU±11.3, 61.9HU±13.3, p=0.010). Hypo-intensity artifacts volume was reduced while hyper-intensity artifacts volume was increased in A2 images compared to A1 and B1 images (47.1ml±14.3, vs. 66.1ml±18.9, 62.7ml±15.9; 72.4ml±17.3, vs. 50.0ml±15.3, 46.2ml±12.9, both p<0.001). A2 images scored significantly higher than A1 images in subjective image quality (p<0.001), and no difference was found between A2 and B1 images (p=0.087). Conclusion: Both OMAR technique and high tube voltage approach improved image quality of CT images in patients with pedicle screw by reducing artifacts.