中文摘要：

目的：通过CT三维影像观测学龄期儿童（7-12岁）寰、枢椎形态结构,探索学龄期儿童寰、枢椎形态特征和增龄变化规律,为学龄期儿童寰、枢椎疾病的早期诊治和预防提供理论依据。方法：收集内蒙古医科大学附属医院及赤峰市第二医院2013-2014年行颈椎CT扫描的学龄期儿童影像资料,排除寰枢椎骨折、畸形、结核等疾病。将收集到的原始DICOM数据导入Mimics 16.0进行三维重建,运用软件的三维测量工具在重建的三维模型上对其寰、枢椎侧块及椎弓根相关指标进行测量,包括寰椎的侧块横径（LMD）、侧块内倾角（d角）、侧块前后径（LMB）、侧块上倾角（e角）、椎弓根宽度（AW）、椎弓根全长（AL）、椎弓根外偏角（b角）、椎弓根高度（AH）及椎弓根尾偏角（c角）;枢椎的椎弓根全长（APL）、椎弓根宽度（APW）、椎弓根外偏角（f角）、椎弓根高度（APH）及椎弓根尾偏角（g角）。将观测对象按年龄每两岁为一组共分三组,即A组（7-8岁）、B组（9-10岁）、C组（11-12岁）,并行统计分析。结果：LMD随年龄递增呈递增趋势,A组左侧为13.91±1.95mm,右侧为14.11±1.95mm;B组左侧为14.31±2.24mm,右侧为14.36±2.39mm;C组左侧为17.18±2.32mm,右侧为17.10±2.41mm;LMD左侧C组与A、B组间有统计学差异（P〈0.05）;LMD在各组左、右侧间比较有差异（P〈0.05）。其他指标也随年龄呈递增趋势,同侧C组与A组比较除f角外均有显著差异（P〈0.05）;同侧C组与B组比较仅AH、APW及APH间存在显著差异（P〈0.05）;同侧A组与B组比较仅AL、AW、APL、APH及g角间存在显著差异（P〈0.05）;同组左、右侧间比较仅LMB和d角间有显著性差异（P〈0.05）。结论：学龄期儿童寰枢椎椎弓根及侧块形态结构复杂,且发育未完全,对各骨性结构发育规律的三维结构形态进行观测,可为临床及进一步研究其周围毗邻结构提供参考依据。

英文摘要：

Objectives： To investigate the CT three-dimensional imaging of morphology of at]antoaxial in school-age children（7-12 years old）, and to provide a theoretical basis for early diagnosis and prevention of atlantoaxial disease in children of school age. Methods： The cervical CT scan data of school-age children images in Chifeng Hospital and the Affiliated Hospital of Inner Mongolia Medical University from 2013 to 2014 were collected, patients with atlantoaxial fractures and deformity, tuberculosis and other diseases were excluded in this study. The original DICOM data were transferred to 3D reconstruction with Mimics 16.0, the software of 3D measurement tools was used to measure the atlantoaxial lateral mass and pedicle related indexes in the reconstruction of three-dimensional model. In atlas, the parameters included lateral mass diameter（LMD）, angle lateral mass block（d）, lateral mass before and after（LMB）, angle lateral mass on the side （e）, atlas pedicle width（AW）, atlas pedicle length（AL）, atlas pedicle outer angle（b）, atlas pedicle height（AH） and atlas pedicle end angle（c）. In axis, the parameters included axis pedicle length（APL）, axis pedicle width （APW）, pivot angle outside vertebral pedicle（f）, axis pedicle height（APH） and axis pedicle end angle（g）. The subjects were divided into three groups according to their age, group A（7-8 years）, group B（9-10 years） and group C（11-12 years old）. Results： The LMD increased with age increasing, the LMD of group A was 13.91± 1.95mm on the left, 14.11±1.95mm on the right; the LMD of group B was 14.31±2.24mm on the left, 14.36± 2.39mm on the right; the LMD of group C was 17.18±2.32mm on the left, 17.10±2.41mm on the right; There were significant differences in left LMD between group C and group A or B （P〈0.05）. There were significant differences in LMD between the left and right side of same group （P〈0.05）. Other parameters also showed a trend of increasing with age, there was