title: Wallerian degeneration of the pyramidal tract does not affect stroke rehabilitation outcome.
abstract: OBJECTIVE
  To test whether Wallerian degeneration (WD) of the pyramidal tract as signaled by MRI affects rehabilitation outcome in patients with subcortical infarction (internal capsule or corona radiata).
  
  
  BACKGROUND
  Recent radiologic evidence suggests that WD occurs no earlier than 3 months after a subcortical infarction.
  
  
  METHODS
  A total of 77 consecutive patients with pure motor hemiparesis due to an initial subcortical infarction were assessed on admission and discharge with the Functional Independence Measure (FIM) for disability and Stroke Impairment Assessment Set (SIAS, full = 25) for impairment. WD was defined by a high-intensity area detected along the pyramidal tract below the level of lesion on T2-weighted MR image (WD+).
  
  
  RESULTS
  Age, sex, side of stroke, Mini-Mental State Examination score, and volume of lesion were comparable for each group. Length of stay (LOS) was significantly longer (p < 0.05) in WD+ (130 days) than in WD- (105 days). There was no difference in the change of FIM (WD+, 99 to 111; WD-, 95 to 107) or SIAS measures (WD+, 12 to 16; WD-, 13 to 16) made on admission and discharge, nor was there any effect of the timing of the rehabilitation experience (< or = 90 days or >90 days after stroke).
  
  
  CONCLUSIONS
  After stroke, apparent WD of the pyramidal tract may slow functional recovery but does not limit final rehabilitation outcome of pure motor hemiparesis. Study of the mechanisms of compensation for this delayed pyramidal tract degeneration will enhance the scientific basis for rehabilitation.
authors.affiliation: Department of Neurology, Toneyama National Hospital, Toyonaka City, Osaka, Japan.
authors.forename: I
authors.initials: I
authors.lastname: Miyai
authors.forename: T
authors.initials: T
authors.lastname: Suzuki
authors.forename: K
authors.initials: K
authors.lastname: Kii
authors.forename: J
authors.initials: J
authors.lastname: Kang
authors.forename: K
authors.initials: K
authors.lastname: Kubota
mesh_terms: D002544:Cerebral Infarction / Q000209:etiology / Q000534:rehabilitation; D002561:Cerebrovascular Disorders / Q000150:complications / Q000534:rehabilitation*; D004185:Disability Evaluation; D005260:Female; D006429:Hemiplegia / Q000209:etiology / Q000534:rehabilitation; D006801:Humans; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000098:blood supply / Q000503:physiopathology; D011712:Pyramidal Tracts / Q000098:blood supply / Q000473:pathology* / Q000503:physiopathology; D016896:Treatment Outcome; D014855:Wallerian Degeneration / Q000209:etiology / Q000534:rehabilitation*