title: Degeneration speed of corticospinal tract in patients with cerebral infarct.
abstract: OBJECTIVE
  Diffusion tensor image tractography (DTT) could be useful for exploring the state of the corticospinal tract (CST) at the level of the subcortical white matter. The purpose of this study was to demonstrate the speed of degeneration of the CST in patients with cerebral infarct, using DTT.
  
  
  METHODS
  Two patients with middle cerebral artery territory infarct were recruited for this study. DTT was performed 5 times with an interval of 7 days, starting at 2 days after onset, using a 1.5-T system with a synergy-L Sensitivity Encoding head coil. The termination criteria used were fractional anisotrophy < 0.3, 0.2, 0.1, respectively, and an angle change > 45 degrees .
  
  
  RESULTS
  Detection of CST degeneration began at the 9 day DTT in both patients. The most rapid CST degeneration was noted for 7 days at 16 days from onset. We did not detect any tract in the affected hemisphere of both patients at the 23-day DTT.
  
  
  CONCLUSIONS
  We demonstrated that CST degeneration begins before 9 days from onset and progresses rapidly in patients with middle cerebral artery territory infarct. It seems that the CST degeneration began earlier than expected.
authors.affiliation: Department of Physical Medicine & Rehabilitation, Yeungnam University College of Medicine, Taegu, Republic of Korea.
authors.forename: Dong Gyu
authors.initials: DG
authors.lastname: Kim
authors.forename: Young Hwan
authors.initials: YH
authors.lastname: Ahn
authors.forename: Woo Mok
authors.initials: WM
authors.lastname: Byun
authors.forename: Tae Gun
authors.initials: TG
authors.lastname: Kim
authors.forename: Dong Suk
authors.initials: DS
authors.lastname: Yang
authors.forename: Sang Ho
authors.initials: SH
authors.lastname: Ahn
authors.forename: Yoon Woo
authors.initials: YW
authors.lastname: Cho
authors.forename: Sung Ho
authors.initials: SH
authors.lastname: Jang
mesh_terms: D000328:Adult; D016880:Anisotropy; D038524:Diffusion Magnetic Resonance Imaging; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000150:complications / Q000473:pathology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011712:Pyramidal Tracts / Q000473:pathology*; D013997:Time Factors