Landmark-based morphometric analysis of first-episode schizophrenia

Background: The goal of this investigation was to utilize landmark-based sh ape analysis and image averaging to determine the sites and extent of speci fic structural changes in first-episode schizophrenia. Methods: Neuroanatomic structures identified on midsagittal magnetic resona nce imaging (MRI) scans were compared between 20 patients with schizophreni a and 22 normal control subjects. The difference bent een averaged landmark configurations in the two groups was visualized as a shape deformation by a thin-plate spline and through averaged MRI images for both groups. Results: A shape difference was found to be statistically significant; by i nspection, it is contrast between differences in two closely abutting regio ns, involving primarily the poster-iol corpus callosum and upper brain sten t - the "focus" is the relation between them. Conclusions: The findings are consistent with prior studies suggesting invo lvement in schizophrenia of the corpus callosum and the limbic structures c ontributing to the corpus callosum; the possibility of local pathology prim arily involving the br-ain stein cannot be excluded. The methods of landmar k-based shape analysis and image averaging utilized in this study can compl ement the "region-of-interest" method of investigating morphometric abnorma lities by characterizing the spatial relationships among structural brain a bnormalities in schizophrenia. Biol Psychiatry 1999;45:1321-1328 (C) 1999 S ociety of Biological Psychiatry.