INCREASE IN CAUDATE NUCLEI VOLUMES OF FIRST-EPISODE SCHIZOPHRENIC-PATIENTS TAKING ANTIPSYCHOTIC-DRUGS

Objective: This study examined the pathomorphology of the caudate nucl ei in first-episode schizophrenic patients with minimal previous neuro leptic exposure. Method: Magnetic resonance imaging (MRI) of the brain was used to examine longitudinally the caudate pathomorphology in 29 first-episode schizophrenic patients and 10 healthy comparison subject s. MRI scans were obtained after the subjects entered the study and at 18-month follow-up. The patients were treated with standardized neuro leptic regimens during the 18-month period. Volumetric assessments of the cerebral cortex, lateral ventricles, and caudate nuclei were perfo rmed on T-1-weighted coronal brain sections. In addition, the patients were systematically evaluated for psychopathology at baseline and dur ing treatment. Results: Caudate volumes increased 5. 7% in the patient s during the 18-month treatment interval, whereas they decreased 1.6% in the comparison subjects over the same time period. Greater amounts of antipsychotic medication received by patients before the first scan and younger age at the time of the first scan were associated with la rger increases in caudate volume. Conclusions: Caudate enlargement occ urs early in the course of treatment in young first-episode schizophre nic patients. This may be a result of an interaction between neurolept ic treatment and the plasticity of dopaminergic neuronal systems in yo ung patients.