Abstract: ［Abstract］〓Objective〖HTSS〗〓To investigate the effects of singlelateral localizer radiography and doubllocalizer radiography images on the radiation dose and image quality of lumbar intervertebral disc computed tomography(CT).
〖HTH〗〖WTHZ〗Methods〖HTSS〗〓One hundred and twelve patients with suspected lumbar intervertebral disc herniation were divided into two groups randomly: 53 cases in singlelocalizer group used a conventional single laterallocalizer radiography scan, 59 cases in doublelocalizer group used lateralorthotopiclocalizer radiography scan. Then these two groups performed routine intervertebral disc sequence scanning by 128 slices spiral CT, respectively. Automatic exposure control(AEC) technology was used. The radiation doses of all scans and the corresponding axial image qualities were analyzed.
〖HTH〗〖WTHZ〗Results〖HTSS〗〓The CT dose of doublelocalizer group of the five variables of L1-2, L2-3, L3-4, L4-5 and L5-S1 were significantly lower than that of singlelocalizer group(P＜005). The results of rank correlation analysis showed that there was a positive correlation between body mass index and scan doses of two groups(P＜005). There was no significant difference in the evaluation of image quality between two groups, except that in L5-S1 of noise and signaltonoise ratio of fat measurement of doublelocalizer group was higher than singlelocalizer group(P＜005).
〖HTH〗〖WTHZ〗Conclusion〖HTSS〗〓For the examination of the lumbar intervertebral disc sequence CT scanning, the lateralorthotopic doublelocalizer radiography images with AEC technology can reduce the radiation dose of the subjects.

Key words: lumbar disc, localizer radiography, radiation dosage