title: Corticospinal tract integrity and lesion volume play different roles in chronic hemiparesis and its improvement through motor practice.
abstract: BACKGROUND
  Initial evidence suggests that the integrity of the ipsilesional corticospinal tract (CST) after stroke is strongly related to motor function in the chronic state but not the treatment gain induced by motor rehabilitation.
  
  
  OBJECTIVE
  We examined the association of motor status and treatment benefit by testing patients with a wide range of severity of hemiparesis of the left and right upper extremity.
  
  
  METHODS
  Diffusion tensor imaging was performed in 22 patients beyond 12 months after onset of stroke with severe to moderate hemiparesis. Motor function was tested before and after 2 weeks of modified constraint-induced movement therapy.
  
  
  RESULTS
  CST integrity, but not lesion volume, correlated with the motor ability measures of the Wolf Motor Function Test and the Motor Activity Log. No differences were found between left and right hemiparesis. Motor performance improved significantly with the treatment regime, and did so equally for patients with left and right arm paresis. However, treatment benefit was not associated with either CST integrity or lesion volume.
  
  
  CONCLUSIONS
  CST integrity correlated best in this small trial with chronic long-term status but not treatment-induced improvements. The CST may play a different role in the mechanisms mediating long-term outcome compared to those underlying practice-induced gains after a chronic plateau in motor function.
authors: 1University of Surrey, Guildford, UK.
authors: Annette
authors: A
authors: Sterr
authors: Phil J A
authors: PJ
authors: Dean
authors: Andre J
authors: AJ
authors: Szameitat
authors: Adriana Bastos
authors: AB
authors: Conforto
authors: Shan
authors: S
authors: Shen
mesh_terms: D000328:Adult; D000368:Aged; D001132:Arm / Q000503:physiopathology*; D001921:Brain / Q000473:pathology; D002908:Chronic Disease; D056324:Diffusion Tensor Imaging; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D009929:Organ Size; D010291:Paresis / Q000473:pathology* / Q000503:physiopathology / Q000534:rehabilitation*; D026741:Physical Therapy Modalities; D011712:Pyramidal Tracts / Q000473:pathology*; D020127:Recovery of Function / Q000502:physiology; D012720:Severity of Illness Index; D016896:Treatment Outcome
keywords: diffusion tensor imaging; hemiplegia; outcome assessment; shaping training; stroke rehabilitation; tractography; upper limb