Arnold-ChiariⅠ畸形MRI分析及发病机制探讨

MRI ANALYSIS AND PATHOGENESIS EXPLORATION IN CHIARI Ⅰ MALFORMATION

目的 :分析后颅窝长、宽、深及小脑扁桃体垂直径 ,枕骨大孔前后径同该病的关系。方法 :对 5 7例ChiariⅠ畸形病例及 5 8例正常对照MRI进行后颅窝大小及小脑扁桃体垂直径 ,枕骨大孔前后径测量 ,采用u检验进行统计学分析。结果 :病理组后颅窝长、宽、深明显小于对照组 ,小脑扁桃体垂直径明显大于对照组 ,两组之间枕骨大孔前后径无显著性差异。结论 :小脑扁桃体垂直径增大对ChiariⅠ畸形诊断有重要价值。

Objective:To analyze the relationship between Arnold-Chiari Ⅰ malformation (ACM-Ⅰ) with the length、width、height of posterior cranial fossa,the vertical diameter of the cerebellar tonsil (VDCT) and the anteroposterior diameter of the foramen magnum (APDFM).Methods:The volume of posterior cranila fossa、VDCT and APDFM were measured in 57 cases of Chiari Ⅰ malformation and 58 normal control subjects using MRI,u test was used statistically.Results:Compared to the control group,there was a significantly smaller posterior cranial fossa and a significantly taller VDCT in the ACM-Ⅰ group.The difference of the APDFM between the two groups was of no significance.Conclusions:Enlargement of the VDCT was of significant diagnostic value.The most possible pathogenesis of ACM-Ⅰ is the underdevelopment of occipital somite originating form the paraxial mesoderm,which induces overcrowding in the posterior cranial fossa..