颈椎管容积和脊髓体积的MRI测量及其动态变化

Dynamic measurement of cervical spinal canal and cervical spinal cord volume

目的利用核磁共振测量正常人的颈椎管容积及脊髓的体积,并探讨其动态变化趋势。方法选取正常人20名,排除退变、畸形和对扫描发生恐惧者4名,利用MRI无间隔梯度扰像回波序列方式分别扫描并测量过屈、中立、过伸位下各颈椎椎管容积和脊髓的体积,并进行统计学分析。结果过屈、中立、过伸三种体位下正常人的颈椎管容积改变趋势为V过屈﹥V中立﹥V过伸,且三个体位下的容积差异有显著性(P<0.05);但三种体位下的枕骨大孔下缘至颈2椎体下缘节段的椎管容积无统计学意义(P>0.05);过屈、中立和过伸位下脊髓的体积差异均无统计学意义(P>0.05),颈段脊髓的体积约10.69±0.56cm3。结论颈椎由过屈向过伸动态变化过程中,颈椎管的容积是逐渐减小的,且颈椎管容积的改变主要发生在颈3～颈7节段;但颈段脊髓的体积是固定不变的,脊髓的形态和在椎管内的位置是变化的。

Objectives To measure the cervical spinal canal and cervical spinal cord volume of healthy people during MRI,and also to evaluate the dynamic changes of the cervical spinal canal and cervical spinal cord volume with the angle change of the cervical vertebrae. Methods Twenty healthy people are chosen to experiment,and four individuals of all are excluded because of degeneration,deformity or in fear of the scan. The remaining 16 individuals are conducted MRI scan. Last,we analyze the conclusions and evaluate their dynamic changes. Results The volume of the cervical spinal canal reduced gradually. The volume was larger in flexion position than in the central position,and the volume was larger in central position than in the extension position,and also they had a significant difference （P〈0.05）,but the volume of cervical spinal cord had not changed with flexion-extension,and had no significant difference （P〉0.05）,the mean volume of cervical spinal cord were about 10.69±0.56cm^3. Conclusion The volume of the cervical spinal canal decreases gradually with increasing extension angle,but the volume of the spinal cord is always the same size with changing the angle of cervical vertebrae,and the shape and location of the spinal cord is changing in the cervical spinal canal.MRI can be used to measure the volume of no apparent degeneration cervical spinal canal and the spinal cord.