title: Peri-infarct reorganization of motor function in patients with pontine infarct.
abstract: OBJECTIVE
  Combined functional MRI (fMRI) and diffusion tensor tractography (DTT) imaging provides a powerful vehicle for the investigation of motor recovery mechanisms. Using this combined method, we investigated the motor recovery mechanism in patients with pontine infarct.
  
  
  METHODS
  We evaluated six healthy control subjects and two patients with pontine infarct at 6 months from onset. fMRI was performed at 1.5 T with timed hand grasp-release movements. For DTT, we used each of the 32 noncollinear diffusion-sensitizing gradients. Three-dimensional reconstructions of the fiber tracts were obtained with FA <0.3, angle >45 degrees as termination criteria.
  
  
  RESULTS
  fMRI data revealed activation only in the contralateral primary sensorimotor cortex during movement of either hand. DTI findings from controls and the unaffected hemisphere of the patients showed that the corticospinal tract descended through the known corticospinal tract pathway. However, the tracts of the affected hemisphere in the patients were observed to pass along peri-infarct areas (patient 1: lateral, patient 2: posterior) in the pons.
  
  
  CONCLUSIONS
  It seems that the peri-infarct areas compensate for corticospinal tract damage at the pons; this may be one mechanism of motor recovery for patients with pontine infarct.
authors.affiliation: Department of Neurosurgery, School of Medicine, Ajou University, Suwon, Republic of Korea.
authors.forename: Young Hwan
authors.initials: YH
authors.lastname: Ahn
authors.forename: Sung H
authors.initials: SH
authors.lastname: You
authors.forename: Marilys
authors.initials: M
authors.lastname: Randolph
authors.forename: Seong Ho
authors.initials: SH
authors.lastname: Kim
authors.forename: Sang Ho
authors.initials: SH
authors.lastname: Ahn
authors.forename: Woo Mok
authors.initials: WM
authors.lastname: Byun
authors.forename: Dong Suk
authors.initials: DS
authors.lastname: Yang
authors.forename: Sung Ho
authors.initials: SH
authors.lastname: Jang
mesh_terms: D000328:Adult; D000368:Aged; D020526:Brain Stem Infarctions / Q000473:pathology* / Q000503:physiopathology*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D020127:Recovery of Function / Q000502:physiology*; D013647:Task Performance and Analysis