The effects of neuroleptic medications on basal ganglia blood flow in schizophreniform disorders: A comparison between the neuroleptic-naive and medicated states

Background: Previous studies indicate that basal ganglia volumes of first-episode neuroleptic-naive patients with schizophrenia are smaller than those of normal control subjects. Subsequent exposure to neuroleptic medication appears to induce volumetric change. Possible reasons for this include differences in blood flow and metabolism between the neuroleptic-naive and medicated states. Methods: We used positron emission tomography (PET) to measure blood flow to the caudate and putamen, in a sample of 29 neuroleptic-naive patients with schizophreniform disorders and 29 matched control subjects. We also studied a subset of the patient sample (n = 13), comparing their "before" versus "on" medication PET scans. Results: We did not find a significant difference in blood flow to the caudate and putamen between neuroleptic-naive patients and control subjects even after controlling for whole brain blood flow; however, in the subset of 13 patients compared in the "on" versus "off" medication states, there was a statistically significant increase in blood flow to both the caudate and putamen. Conclusions: Before treatment, there appears to be no difference in striatal blood flow between first-episode neuroleptic-naive patients and healthy volunteers, but there appears to be a significant increase in blood flow to the striatum after the treatment is initiated. (C) 2002 Society of Biological Psychiatry.