Internal capsule, corpus callosum and long associative fibers in good and poor outcome schizophrenia: a diffusion tensor imaging survey.
BACKGROUND
Prior voxelwise studies of white matter anisotropy found widespread reductions involving all major fiber tracts of the schizophrenic brain. We set out to confirm these exploratory findings and evaluate their relation to illness severity using a hypothesis-driven region-of-interest approach.


METHODS
104 schizophrenia patients (51 with good outcomes, 53 with poor outcomes) and 41 matched comparison subjects participated in the study. Regions of interest were selected on the basis of published voxelwise findings and placed within major fiber tracts using Talairach's stereotaxic coordinates.


RESULTS
Fractional anisotropy reductions in schizophrenia patients were confirmed in the left cingulum, anterior thalamic radiation, fronto-occipital and inferior longitudinal fasciculi, as well as bilaterally in the corpus callosum, anterior and posterior limbs of internal capsule, superior longitudinal fasciculus, optic radiation, and frontotemporal extrafascicular white matter. Anisotropy reductions were more extensive in patients with poor outcomes ("Kraepelinian"), particularly in the posterior corpus callosum, fronto-occipital fasciculus, left optic radiation and frontotemporal white matter. Lower anisotropy in the right hemisphere tracts was associated with more prominent positive symptomatology, whereas negative symptoms were inversely associated with anisotropy values in both hemispheres.


CONCLUSIONS
These results support a global neural disconnectivity in schizophrenia patients, which is more severe in those with poor clinical outcomes.
Mitelman
Serge A
SA
Department of Psychiatry, Mount Sinai School of Medicine, New York, New York, USA. serge.mitelman@mssm.edu
Torosjan
Yuliya
Y
Newmark
Randall E
RE
Schneiderman
Jason S
JS
Chu
King-Wai
KW
Brickman
Adam M
AM
Haznedar
M Mehmet
MM
Hazlett
Erin A
EA
Tang
Cheuk Y
CY
Shihabuddin
Lina
L
Buchsbaum
Monte S
MS
D000328:Adult; D001244:Association; D003337:Corpus Callosum / Q000033:anatomy & histology*; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D020772:Internal Capsule / Q000033:anatomy & histology*; D008297:Male; D009412:Nerve Fibers / Q000473:pathology*; D009415:Nerve Net / Q000503:physiopathology*; D012559:Schizophrenia / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy; D017211:Treatment Failure