The Effect of Haloperidol on Regional Cerebral Blood Flow Assessed with 99m-Tc-ECD SPECT In Schizophrenic Patients

Cheon, Keun Ah; Lee, Jong Doo; Min, Sung Kil; Kim, Se Joo; Ahn, Suk Kyoon

Abstract

OBJECTIVES: Regional cerebral blood flow(rCBF)in schizophrenics is confounded by various factors including medication status. Previously, there have been numerous studies regarding the effects of antipsychotics on rCBF. However, these works have shown contradictory and inconsistent findings due to the different of type, dose and exposed duration of antipsychotics. The aim of this study was to observe the effect of antipsychotic medication on rCBF and exposed duration of antipsychotics under control.
METHODS
Eighteen drug-naive schizophrenics and 19 schizophrenics medicated with haloperidol were included in the study. Regional cerebral blood flow was assessed with the singlephoton emission computed tomography(SPECT)under a resting state. Relative rCBF was compared between two groups. Haloperidol was selected as the antipsychotic drug as it has relatively selective action at the D2 receptor and less active metabolites. Exposed duration was limited from one to three weeks.
RESULTS
Haloperidol-medicated schizophrenic patients had a significantly greater increase of relative cerebral perfusion in the right inferior temporal lobe, left inferior frontal lobe, both basal ganglia, left thalamus, both parieto-occipital lobes, and right parietal lobe than drug-naive schizophrenic patients. Haloperidol-medicated schizophrenic patients had a significant decrease of relative cerebral perfusion in left inferior temporal lobe. However, no significant differences in relative rCBF were found between drug-naive and haloperidol-medicated schizophrenic patients in right inferior frontal lobe, right thalamus, both superior temporal lobes, both superior frontal lobes, and left parietal lobe.
CONCLUSION
These findings suggest that antipsychotics affect regional cerebral blood flow, and antipsychotic medication status must be considered in the relative rCBF studies of schizophrenic patients.