Brain CSF volume in patients with first-episode psychosis

Volume measurement of MRI has revealed structural abnormalities in chronic schizophrenics. In this study, MR scans were obtained from 17 patients with first-episode psychosis and 12 age-gender matched normal controls. Nine patients were diagnosed with probable affective disorder and 8 were diagnosed with probable schizophrenia (follow up will be used for final diagnosis). The MR scans were obtained on a 1.5 Tesla magnet using an axial spin-echo acquisition. Voxel dimensions were 0.9 by 0.9 by 3.0, data were stored as 50-54 double echo 3-mm slices. Automated segmentation methods, 3D slice editing techniques which allowed reformatting of slices in three different planes, and 3D surface rendering techniques were then applied to these data sets to create 3D representations of the total volume of intracranial space (ICS), gray matter, white matter, lateral ventricles, temporal horns, and cerebrospinal fluid (CSF). There were no significant differences for the volumes in total ICS, gray matter or white matter among three groups. CSF in schizophrenia was larger than in affective disorder and controls [F(2,26)=4.332, p=0.023]. Left (12.40±6.13 ml) > right (9.83±5.60) asymmetry was also noted in lateral ventricles of schizophrenics [group × side; F(2,26)=2.986, p=0.0680] (left, 9.50±3.31; right, 9.62±4.73 in affective disorder; left, 8.19±5.07; right, 8.61±4.60 in controls). Both left (0.572±0.232) and right (0.669±0.255) temporal horns in schizophrenia were larger than those in affective disorder (left, 0.334±0.148; right, 0.392±0.156) and controls (left, 0.385±0.157; right, 0.360±0.197) [F(2,26)=6.118, p=0.0066]. No asymmetry was observed in the temporal horns among three groups. These findings suggest that some structural abnormalities in schizophrenia are present at early stages of the illness.