title: Preoperative weakness and demyelination of the corticospinal tract in meningioma patients : changes in diffusion parameters using diffusion tensor imaging.
abstract: OBJECTIVE
  Differentiation of demyelination in white matter from axonal damage can be determined using diffusion tensor imaging (DTI). In this study using meningioma patients an attempt was made to evaluate the relationship between preoperative weakness and the changes of diffusion parameters in the corticospinal tract (CST) using DTI.
  
  
  METHODS
  Twenty-six patients with meningioma were enrolled in this study. Eleven of them suffered from objective motor weakness and were classified as Group 1. The remaining 15 patients did not present motor weakness and were classified as Group 2. Fiber tractography and CST diffusion parameters were obtained using DTIStudio. The ratios (lesion side mean value/contralateral side mean value) of CST diffusion parameters were compared with 1.0 as a test value using a one-sample t-test.
  
  
  RESULTS
  In Group 1, fractional anisotropy (FA), tensor trace (TT), and radial diffusivity (RD, λ2 and λ3) of the CST were significantly different between two hemispheres, but axial diffusivity (AD, λ1) of the CST was not significantly different between two hemispheres. In Group 2, FA and λ3 of CST did not differ significantly between the hemispheres. In Group 2, TT, λ1, and λ2 of CST in the ipsilateral hemisphere were significantly higher than those of the unaffected hemisphere. However, the differences were small.
  
  
  CONCLUSIONS
  Motor weakness was related to a low FA and high TT resulting from increased RD of the CST fibers. CST diffusion changes in patients with weakness are similar to those for demyelination.
authors.affiliation: Department of Neurosurgery, Seoul Paik Hospital, Inje University College of Medicine, Seoul, Korea.
authors.forename: Myoung Soo
authors.initials: MS
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, Seoul National University College of Medicine, Seoul, Korea. ; Neuroscience Research Institute, Seoul National University Medical Research Center, Seoul, Korea. ; Clinical Research Institute, Seoul National University Hospital, Seoul, Korea.
authors.forename: Chun Kee
authors.initials: CK
authors.lastname: Chung
authors.affiliation: Department of Neurosurgery, Seoul National University College of Medicine, Seoul, Korea. ; Neuroscience Research Institute, Seoul National University Medical Research Center, Seoul, Korea. ; Clinical Research Institute, Seoul National University Hospital, Seoul, Korea.
authors.forename: Hee-Won
authors.initials: HW
authors.lastname: Jung
authors.affiliation: Department of Neurosurgery, Seoul National University College of Medicine, Seoul, Korea. ; Neuroscience Research Institute, Seoul National University Medical Research Center, Seoul, Korea. ; Clinical Research Institute, Seoul National University Hospital, Seoul, Korea.
authors.forename: Chul-Kee
authors.initials: CK
authors.lastname: Park
authors.affiliation: Department of Neurosurgery, Seoul National University College of Medicine, Seoul, Korea. ; Neuroscience Research Institute, Seoul National University Medical Research Center, Seoul, Korea. ; Clinical Research Institute, Seoul National University Hospital, Seoul, Korea.
authors.forename: Chi Heon
authors.initials: CH
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, Seoul National University College of Medicine, Seoul, Korea. ; Neuroscience Research Institute, Seoul National University Medical Research Center, Seoul, Korea. ; Clinical Research Institute, Seoul National University Hospital, Seoul, Korea.
authors.forename: June Sic
authors.initials: JS
authors.lastname: Kim
keywords: Corticospinal tract; Demyelination; Diffusion; Diffusion tensor imaging; Weakness