title: Experimental study on MRI evaluation of the course of cervical spinal cord injury.
abstract: METHODS
  An experimental study was conducted to evaluate MRI signal changes within the spinal cord after the injury in rats.
  
  
  OBJECTIVE
  To clarify the significance of MRI signal changes in the injured cervical cord.
  
  
  METHODS
  Tokyo, Japan.
  
  
  METHODS
  Cervical spinal cord injury was produced in rats by placing a 20-g, or 35-g weight on exposed dura at the C6 level for 5 min (20 g- or 35 g-compression group). Motor function was evaluated by the inclined-plane method at 2, 7 and 28 days after the injury. T1- and T2-weighted images were produced by the spin-echo method with a static magnetic field strength of 2.0 tesla, at 2 and 28 days after the injury, and then the histopathological examinations were performed.
  
  
  RESULTS
  In the 20-g compression group, which recovered from the paralysis at 28 days, MR images were T1 iso signal/T2 high signal 2 days after the injury and T1 iso signal/T2 high signal after 28 days. The changes in MRI signal 2 and 28 days represented edema and gliosis, respectively. In the 35-g compression group, which incompletely recovered from paralysis at 28 days. MR images were T1 iso-signal/T2 low signal surrounded by high signal 2 days after the injury and T1 low/T2 high signal at 28 days. The MRI signal changes 2 and 28 days reflected hemorrhage with edema and cavities, respectively.
  
  
  CONCLUSIONS
  T2 low signal of the spinal cord observed early after injury reflects hemorrhage and may serve as an indicator of a poor prognosis. T1 low/T2 high signals from the subacute to chronic period indicated persistence of paralysis and limited recovery of function.
authors.affiliation: Department of Orthopaedic Surgery, School of Medicine, Keio University, Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Ohta
authors.forename: Y
authors.initials: Y
authors.lastname: Fujimura
authors.forename: M
authors.initials: M
authors.lastname: Nakamura
authors.forename: M
authors.initials: M
authors.lastname: Watanabe
authors.forename: Y
authors.initials: Y
authors.lastname: Yato
mesh_terms: D000818:Animals; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging; D009068:Movement / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D013116:Spinal Cord / Q000378:metabolism; D013119:Spinal Cord Injuries / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology
chemical_list: D005904:Glial Fibrillary Acidic Protein