Functional neuroimaging in first-episode psychosis

Twenty-one inpatients (15 males/6 females) with an average age of 23.7 years, who had been diagnosed with FEP according to DSM-IV-TR (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition,Text Revision) criteria, were evaluated using the Positive and Negative Syndrome Scale (PANSS). SPECT was acquired after injection of Tc-HMPAO (Tc-hexamethylpropyleneamine oxime), before drug treatment and again after 3 months of treatment with either risperidone (mean dose 4.8 mg/day, in 7 patients with predominantly negative symptoms), olanzapine (mean dose 11.6 mg/day, in 9 patients with predominantly positive symptoms), and quetiapine (mean dose 440 mg/day, in 5 patients with predominantly positive symptoms). Exclusion criteria included the presence of a neurological or other somatic disorder that could modify rCBF, and previous exposure to antipsychotic drug treatment.