MRI analysis of spinal cord outlet of skull base on formation of syringomyelia in Chiari Ⅰ malformation / 中国医学影像技术

ABSTRACT

Objective To investigate the mechanism and effect of the spinal cord outlet of the skull base on Chiari Ⅰ malformation with syringomyelia.Methods The cervical spinal cord stem angle (Anbc),slope angle of cervical vertebra (Ansc) of Chiari Ⅰ malformation were measured.In foramen magnum (Llf) and anterior vertebral canal level (Laf),spinal canal(Ac),spinal cord (As) and inferior hernia area (Ah) were measured.Angle,area and ratio were compared in Chiari Ⅰ malformation with syringomyelia,Chiari Ⅰ malformation without syringomyelia and normal control group.Results Ansc,Anbc-Ansc had significant differences among control group and Chiari Ⅰ malformation patients (all P＜0.001).In Llf,Laf,As had significant differences among three groups (all P＜0.05),further comparison of the two showed there were significant differences between Chiari Ⅰ malformation with syringomyelia patients and control group,Chiari Ⅰ malformation without syringomyelia patients and control group in Llf(all P＜0.05).In Llf,Laf,Ac in Chiari Ⅰ malformation with syringomyelia was smaller than control group (P＜0.05).Ah in Llf,Lafand Lh in Llf had no statistical significant difference between Chiari Ⅰ malformation with and without syringomyelia patients (all P＞0.05).In Llf,Laf,As/Ac had statistical significant difference among Chiari Ⅰ malformation with and without syringomyelia patients,control group (all P＜0.001),further comparison of the two showed As/Ac in Llf had statistical significance difference between Chiari Ⅰ malformation with syringomyelia patients and control group (P＜0.05),As/Ac in La had statistical significance difference between Chiari Ⅰ malformation with syringomyelia patients and control group,between Chiari Ⅰ malformation without syringomyelia patients and control group (all P＜0.05),Conclusion The cervical spinal cord,Ansc reducing,narrow vertebral proportion increase are important factors to promote Chiari Ⅰ malformation syringomyelia.