The authors examined the reports of MRI brain studies of 69 patients with DSM-III-R-diagnosed psychotic disorders (30 early-onset and 24 late-onset schizophrenia patients and 15 with other psychoses) and 41 normal comparison subjects. Participants' ages ranged from 45 to 87 years. A qualitative rating scheme determined type and severity of clinically detectable abnormalities, including volume loss, infarcts, lacunae, and white matter hyperintensities. In this clinically well-characterized sample, the vast majority of the MRIs were within normal limits. There were no significant differences between psychosis patients and normal comparison subjects or between early-onset and late-onset schizophrenia patients in frequency, type, or severity of gross structural abnormalities. The results indicate that late-onset schizophrenia and related disorders can exist without clinically significant gross structural abnormalities in the brain.