Defining the course of brain structural change and plasticity in schizophrenia.

Recent evidence from controlled CT and MRI longitudinal studies suggests that some cerebral ventricular enlargement and hemispheric volumetric reductions (e.g. cerebral atrophy) may have a progressive component in patients with schizophrenia. These studies vary in cohort composition, stage of illness examined, duration of follow-up interval, imaging techniques used, and specific brain regions with findings. They also conflict with earlier evidence suggesting that schizophrenia is a neurodevelopmental disorder with brain pathological deviance occurring prior to the illness onset. The newer brain imaging reports may be detecting subtle brain plasticity that results from a continuing cortical disruptive process, may be epi-phenomena caused by scanning and image analysis artifacts or may possibly reflect systemic physiological fluctuations. Future longitudinal studies of subjects at all stages of illness using a variety of new technologies are needed to clarify these findings.