Dural band pathology in syringomyelia with Chiari type I malformation


Correspondence: NishioNakamura MD, Department of Laboratory Technology, College of Medical Technology, Hokkaido University, Kita 12, Nishi 5, Kita-ku, Sapporo 060-0812, Japan


Surgical material taken from the ‘outer layer’ of thickened dura mater (dural band) at the craniovertebral junction of eight cases of syringomyelia with Chiari type I malformation was histologically examined in comparison with four autopsy cases as controls. The dural band was thickened and there were increased numbers of collagen fibers which showed fiber splitting, hyalinous nodule, calcification and/or ossification. These changes were not observed in the four control cases. Thus, it is suggested that the thickening of the dura mater may be a causative factor of syringomyelia with Chiari type I malformation. In addition, the histology of the thickened dura mater suggests the condition may be a consequence of birth injury in these patients.