Abstract：Objective: To investigate the combined application value of low tube voltage and iterative reconstruction(IR) for CT imaging of the orbit. Methods: From June 2014 to January 2015 in our hospital, 90 patients were referred for orbit CT. Patients were randomly assigned into three groups: 120 kV group(group A), 100 kV group(group B) and 80 kV group(group C), with 30 cases in each group. Group A underwent filtered back projection(FBP) reconstruction while group B and C underwent IR reconstruction. Subjective and objective evaluations were performed on image quality and radiation dose was recorded for each group, which were statistically analyzed. Results: The average effective dose of group A, B and C were (7.3±0.7) mSv, (4.5±0.3) mSv and (2.2±0.2) mSv respectively. There were significant difference among groups. The images of the three groups all met the diagnostic requirement. All image quality scores were higher than 3 points. The consistency of the two observers in evaluating image quality was either good or very good. The image background noise of low-dose group was higher than that of standard dose group, and the difference was statistically significant(P<0.05). Conclusion: Low tube voltage combined with IR algorithm in orbit CT examination can significantly reduce radiation dose, and the image quality can meet the diagnostic requirement.
2015, Vol. 26 
