A review of diffusion tensor imaging studies in schizophrenia

M. Kubicki, R. W. McCarley, C.-F. Westin, H. J. Park, S. Maier, R. Kikinis, F. A. Jolesz, M. E. Shenton
J Psychiatr Res.
2005

Abstract

Both post-mortem and neuroimaging studies have contributed significantly to what we know about the brain and schizophrenia. MRI studies of volumetric reduction in several brain regions in schizophrenia have confirmed early speculations that the brain is disordered in schizophrenia. There is also a growing body of evidence suggesting that a disturbance in connectivity between different brain regions, rather than abnormalities within the separate regions themselves, are responsible for the clinical symptoms and cognitive dysfunctions observed in this disorder. Thus an interest in white matter fiber tracts, subserving anatomical connections between distant, as well as proximal, brain regions, is emerging. This interest coincides with the recent advent of diffusion tensor imaging (DTI), which makes it possible to evaluate the organization and coherence of white matter fiber tracts. This is an important advance as conventional MRI techniques are insensitive to fiber tract direction and organization, and have not consistently demonstrated white matter abnormalities. DTI may, therefore, provide important new information about neural circuitry, and it is increasingly being used in neuroimaging studies of psychopathological disorders. Of note, in the past five years 18 DTI studies in schizophrenia have been published, most describing white matter abnormalities. Questions still remain, however, regarding what we are measuring that is abnormal in this disease, and how measures obtained using one method correspond to those obtained using other methods? Below we review the basic principles involved in MR-DTI, followed by a review of the different methods used to evaluate diffusion. Finally, we review MR-DTI findings in schizophrenia.

Different methods for visualizing diffusion tensor information - left panel - map of fractional anisotropy with higher intensity representing more anisotropic diffusion, middle panel - color map, where different intensities of the three colors indicate the size and the ADC in each of the three Cartesian directions; right panel - blue lines representing the in-place component of the principal diffusion direction, and a color-coded out-of-plane component (more intuitive approach, where each line represents the main diffusion direction for local neighborhood, rather than for each voxel).

Reference

Kubicki M, McCarley RW, Westin CF, Park HJ, Maier S, Kikinis R, Jolesz FA, Shenton ME. A review of diffusion tensor imaging studies in schizophrenia. J Psychiatr Res 2005;.

Bibtex entry

@Article{kubickiJPR05,
  author         = {M. Kubicki and R. W. McCarley and C. F. Westin and H. J.   
                   Park and S. Maier and R. Kikinis and F. A. Jolesz and M. E. 
                   Shenton},                                                   
  title          = {A review of diffusion tensor imaging studies in            
                   schizophrenia},                                             
  journal        = {J Psychiatr Res.},                                         
  year           = {2005},                                                     
  annote         = {review}
}