Mid-sagittal anatomy in late-onset schizophrenia

Background, Of the midline brain structures, abnormalities have been demons trated in the corpus callosum and cerebellum in young schizophrenic patient s. Whether similar abnormalities are also present in late-onset schizophren ia (LOS) is not known. Methods. The mid-sagittal cross-sectional areas of brain regions, in partic ular the corpus callosum and cerebellum, on magnetic resonance imaging were examined ina group of patients with late-onset schizophrenia (N = 25) and contrasted with two comparison groups - early-onset schizophrenia (EOS) (N = 24) and healthy volunteers (NC) (N = 30) matched for age and gender. Results. While the mean corpus callosum area in the LOS group was smaller t han in the EOS (by 10.2 %) and NC (by 6.2 %) groups, the three groups did n ot differ statistically in the corpus callosum area or the corpus callosum to cerebrum ratios. The cross-sectional cerebellar areas or the cerebellum: cerebrum ratios also did not differ across the groups. The brainstem was sm aller in the schizophrenic groups because of smaller cross-sectional areas of the pens, a statistically significant difference which could not be acco unted for by any gross lesions on visual inspection. Conclusion. We found no abnormality in the mid-sagittal area of the corpus callosum and cerebellum in our early- or late-onset schizophrenia subjects. The significance of the finding of a smaller pontine cross-sectional area is unclear and speculation on it awaits independent replication using a vol umetric measure.