ABSTRACT
Objective To evaluate the clinical value of low kVp with iterative reconstruction in multislice spiral computed tomography of lumber vertebrae in young soldiers. Methods Sixty young soldiers who suffered from lumbar diseases were randomly divided into a control group(120 kVp)and a test group(100 kVp),who underwent CT examination with 120 kVp tube voltage in the control group and 100 kVp tube voltage in the test group.The control group went through filtered back projection (FBP)for image reconstruction.The test group applied FBP or sinogram-affirmed iterative reconstruction(SAFIRE)based on image reconstruction requirements,and then were divided into FBP test group and SAFIRE test group.The noise and SNR (signal to noise ratio)of the images were measured in each group.Meanwhile two experienced radiologists evaluated the quality of images.CTDIvol,DLP and ED were used to measure the scan dose in each group.Mean tube current was recorded by CARE Dose 4D.The data were analyzed with SPSS.Results There were no significant difference between the objective and subjective image evaluations in SAFIRE test group and the control group (P>0.05),while there were statistical differences between FBP test group and the control group or between the two test groups(P<0.05).The radiation doses in the test groups were both lower significantly than that in the control group,and the ED values in the test groups were decreased by 43% when compared with the control group. The test groups had the tube voltages not obviously different from that in the control group (P>0.05). Conclusion The radiation dose in the lumbar multislice spiral CT examination of young soldiers is decreased significantly when the tube voltage falls to 100 kVp,the same image quality as that by conventional 120 kVp tube voltage can be obtained by combining iterative reconstruction.