Brain abnormalities observed in childhood-onset schizophrenia: a review of the structural magnetic resonance imaging literature.

Childhood-onset schizophrenia (COS) is a rare, severe form of schizophrenia in which there are structural brain abnormalities that may be related to the psychotic symptomatology and neurocognitive deficits found in these patients. While there are numerous structural imaging studies of the adult-onset variant of schizophrenia (with many conflicting findings), relatively few brain imaging studies of COS have been conducted. This paper summarizes the extant literature of magnetic resonance imaging (MRI) studies of structural brain abnormalities in COS, and compares findings to similar studies of adult-onset patients. Volumetric MRI studies of COS patients have consistently shown evidence for increased ventricular volume, reduced cerebral gray matter, and increased caudate volume, consistent with findings from adult-onset studies. Other volumetric brain abnormalities are observed in COS patients, such as reduced total brain volume, but not consistently across all studies. Voxel-based morphometric analyses have revealed abnormalities in the shape and spatial location of structures in COS such as the corpus callosum, caudate, and thalamus that could not be observed in the more traditional volumetric assessments. Similar findings also are observed in adult-onset patients. Progressive degenerative changes, such as ventricular enlargement, appear to occur in COS only until young adulthood where there is an apparent asymptote with no further degenerative changes. This is consistent with the lack of progressive changes noted in most longitudinal studies of adult-onset schizophrenia.