Structural brain imaging in biological psychiatry.

The application of X-ray CT and magnetic resonance imaging to the study of brain structure in psychiatry research is reviewed. In schizophrenia, CT showed minor enlargements of fluid spaces; MR has shown volume reductions in medial temporal lobe structures and, most recently, general cortical grey matter. In affective disorders, subcortical white matter lesions seem to characterise particular subgroups. In childhood autism, no clear consensus has emerged despite earlier claims for cerebellar pathology. In dementia, medial temporal changes can be detected reliably in Alzheimer's disease and are of diagnostic and prognostic importance.