title: Changes in white matter integrity follow excitatory rTMS treatment of post-stroke aphasia.
abstract: OBJECTIVE
  In this study, we examine whether an excitatory repetitive transcranial magnetic stimulation (rTMS) protocol called intermittent theta burst stimulation (iTBS) applied to the affected left hemisphere leads to changes in white matter fractional anisotropy (FA).
  
  
  METHODS
  Diffusion tensor imaging (DTI) data were collected in 8 aphasic stroke patients before and after 10 daily iTBS treatments. Alignment of structural and DTI data and derivation of diffusion index maps were performed using Analysis of Functional NeuroImages software followed by Tract-Based Spatial Statistics using FMRIB Software Library. Paired t-tests were performed to compare pre- to post-rTMS changes in FA.
  
  
  RESULTS
  There were significant (p < 0.001) left-hemispheric FA increases near the inferior and superior frontal gyri and anterior corpus callosum. FA also increased in the right midbrain and bilaterally near temporal, parietal and posterior cingulate regions. FA decreased bilaterally near the fusiform gyrus and in left cerebellum.
  
  
  CONCLUSIONS
  Overall, left-hemispheric regions that showed increased FA corresponded to areas previously shown to have increases in fMRI language activation after iTBS. The increased white matter integrity near the stimulation sites may reflect improvements in cortical function mediated by excitatory rTMS through its ability to facilitate synaptic connections.
authors.affiliation: Department of Neurology, University of Cincinnati Academic Health Center, Cincinnati, OH, USA. Jane.Allendorfer@uc.edu
authors.forename: Jane B
authors.initials: JB
authors.lastname: Allendorfer
authors.forename: Judd M
authors.initials: JM
authors.lastname: Storrs
authors.forename: Jerzy P
authors.initials: JP
authors.lastname: Szaflarski
mesh_terms: D000328:Adult; D000368:Aged; D016880:Anisotropy; D001037:Aphasia / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy*; D001931:Brain Mapping / Q000379:methods; D003337:Corpus Callosum / Q000473:pathology / Q000503:physiopathology; D056324:Diffusion Tensor Imaging; D005260:Female; D005625:Frontal Lobe / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D007807:Language Tests; D008297:Male; D008636:Mesencephalon / Q000473:pathology / Q000503:physiopathology; D008875:Middle Aged; D009413:Nerve Fibers, Myelinated / Q000473:pathology* / Q000502:physiology; D009473:Neuronal Plasticity / Q000502:physiology; D020521:Stroke / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy*; D013826:Theta Rhythm / Q000502:physiology; D050781:Transcranial Magnetic Stimulation / Q000379:methods*