PET and MRI of the thalamus in never-medicated patients with schizophrenia

Abstract

OBJECTIVE: This study reports the first paired measurements of glucose metabolism and size of thalamic regions in never-medicated schizophrenic patients using coregistered magnetic resonance imaging (MRI) templates. METHOD: Positron emission tomography with [18F]fluorodeoxyglucose and matching MRI scans were obtained in 20 never-medicated patients with schizophrenia and 15 normal volunteers. Methods for thalamic edge finding, statistical testing of shape differences with chi-square maps, and MRI localization of major thalamic subregions were developed. RESULTS: Patients with schizophrenia showed a diminished metabolic rate in the right thalamus, with a loss of the normal pattern of right greater than left asymmetry. Division into anterior/posterior segments revealed that the left anterior and right posterior showed the decrease. Differences were greater for metabolism in the weighted thalamic area (ratexarea) than for rate per unit area, a finding consistent with reported greater decreases in total neuron...