Analysis of possible relating factors about syringomyelia in Chiari I malformation

Objective: To analyse the possible relating factors about syringomyelia in Chiari I malformation(CM I). Methods: The MRI records of 142 CM I patients at Kailuan Hospital from 1991 to 2001 were collected retrospectively. Of the 142 patients, 67 were diagnosed as CM I with and 75 without syringomyelia. The relation of development of syringomyelia in patients with CM I to the extent of cerebellar tonsillar herniation, antereoposterior diameter of foramen magnum(D), antereoposterior diameter of cerebellar tonsil herniated through foramen magnum(d) and d/D were analysed. Results: The development of syringomyelia in patients with CM I had no relationship with D, d and d/D. The length of cavity had relationship with d. There were relationship between the anteroposterior diameter, the transverse diameter of cavity and cerebrospinal fluid velocity phenomenon(CFVP). Conclusion: ①Development of syringomyelia have no relationship with the degree of cerebellar tonsillar herniation, D, d, d/D. ②There is relationship between the length of cavity and d. ③The anteroposterior diameter and the transverse diameter of cavity are related to the presence of CFVP in the cavity.