Ventricle-to-brain ratio (VBR) was measured from the computed tomographic (CT) scans of 33 very recent-onset psychotic patients. Illness severity and positive and negative symptoms were also assessed in 21 of these patients with schizophreniform disorder. Forty-five neurology patients served as controls. Analyses revealed no significant differences between the VBR of the psychotic group as a whole, the schizophreni-form subgroup, the affective psychotic subgroup, and the controls. Control subjects with a neurological diagnosis of vertigo or syncope had significantly higher VBR than the remainder of the control group and the psychotic group. When the psychotic group was compared to the control group minus those controls with syncope or vertigo, the psychotic group had significantly higher VBR. The schizophreniform subgroup also had significantly higher VBR than the control group minus subjects with vertigo or syncope. In the schizophreniform subgroup, positive symptoms and illness severity were associated with smaller VBR. There was no association between negative symptoms and VBR.