The amygdala in schizophrenia: a trimodal magnetic resonance imaging study.
In schizophrenic psychoses, structural and functional alterations of the amygdala have been demonstrated by several neuroimaging studies. However, postmortem examinations on the brains of schizophrenics did not confirm the volume changes reported by volumetric magnetic resonance imaging (MRI) studies. In order to address these contradictory findings and to further elucidate the possibly underlying pathophysiological process of the amygdala, we employed a trimodal MRI design including high-resolution volumetry, diffusion tensor imaging (DTI), and quantitative magnetization transfer imaging (qMTI) in a sample of 14 schizophrenic patients and 14 matched controls. Three-dimensional MRI volumetry revealed a significant reduction of amygdala raw volumes in the patient group, while amygdala volumes normalized for intracranial volume did not differ between the two groups. The regional diffusional anisotropy of the amygdala, expressed as inter-voxel coherence (COH), showed a marked and significant reduction in schizophrenics. Assessment of qMTI parameters yielded significant group differences for the T2 time of the bound proton pool and the T1 time of the free proton pool, while the semi-quantitative magnetization transfer ratio (MTR) did not differ between the groups. The application of multimodal MRI protocols is diagnostically relevant for the differentiation between schizophrenic patients and controls and provides a new strategy for the detection and characterization of subtle structural alterations in defined regions of the living brain.
Kalus
Peter
P
Clinic for Psychiatry and Psychotherapy, Charité University Medicine, Campus Mitte, Psychiatrische Universitätsklinik der Charité im St. Hedwig-Krankenhaus, Turmstrasse 21, D-10559, Berlin, Germany. peter.kalus@charite.de
Slotboom
Johannes
J
Gallinat
Jürgen
J
Wiest
Roland
R
Ozdoba
Christoph
C
Federspiel
Andrea
A
Strik
Werner K
WK
Buri
Caroline
C
Schroth
Gerhard
G
Kiefer
Claus
C
D000328:Adult; D000679:Amygdala / Q000473:pathology*; D000704:Analysis of Variance; D001931:Brain Mapping; D016022:Case-Control Studies; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D012559:Schizophrenia / Q000473:pathology* / Q000503:physiopathology