A controlled study of 99mTc-HMPAO single-photon emission imaging in chronic schizophrenia.

Regional cerebral blood flow (rCBF) during a word fluency task was compared in twenty-five male, right-handed, medicated schizophrenic patients and twenty-five age-matched male, right-handed healthy volunteers, using 99mtechnetium-HMPAO multidetector single-photon emission tomography. Increased rCBF in caudate and thalamus was found in patients, probably secondary to neuroleptic medication. Patients showed decreased rCBF in left frontal cortical regions and increased rCBF in left posterior cortical regions, compared to controls. Patterns of left-sided frontal rCBF dominance in controls were reversed in patients, as were normal patterns of right-sided parietal rCBF dominance. Negative symptom score correlated inversely with mesial frontal rCBF, particularly on the left.