An MRI study of basal ganglia volumes in first-episode schizophrenia patients treated with risperidone

Objective: The basal ganglia may contribute to extrapyramidal movement diso rders, affective disturbances, and cognitive deficits in schizophrenia. Bas al ganglia volumes are putatively affected by antipsychotic medications. Th e purpose of this study was to determine the long-term effects of risperido ne treatment in a cohort of first-episode patients with schizophrenia. Method: The subjects were 30 patients with first-episode schizophrenia, 12 patients chronically treated with typical antipsychotics, and 23 healthy co mparison subjects. They were scanned by magnetic resonance imaging at basel ine. The first-episode patients received 1 year of continuous risperidone t reatment, after which they and the comparison subjects were rescanned. Caud ate, putamen, and globus pallidus volumes were determined from coronal imag es. Results: The baseline caudate, putamen, and globus pallidus volumes were si gnificantly larger in the chronically treated patients than in the untreate d first-episode subjects and comparison subjects. These volumes did not dif fer between the first-episode patients and healthy comparison subjects. Bas al ganglia volumes were unchanged after 1 year of exposure to risperidone i n the first-episode subjects. Extrapyramidal movement disorders were presen t in the majority of chronically treated patients and more than one-third o f the never-medicated first-episode patients at baseline. Conclusions: This group of first-episode patients did not exhibit abnormali ties of basal ganglia volumes, nor were basal ganglia volumes affected by e xposure to risperidone. Movement disorders were observed in both first-epis ode and chronically treated patients, suggesting effects of both illness an d medications.