Volumetric Differences in Gray and White Matter of Cerebellar Crus I/II across the Different Clinical Stages of Schizophrenia.

Aim Schizophrenia is considered to be a disorder of progressive structural brain abnormalities. Previous studies have indicated that the cerebellar Crus I/II plays a critical role in schizophrenia. We aimed to investigate how specific morphological features in the Crus I/II at different critical stages of the schizophrenia spectrum contribute to the disease. Methods The study involved 73 participants on the schizophrenia spectrum (28 with ultra-high risk for psychosis [UHR], 17 with first-episode schizophrenia [FES], and 28 with chronic schizophrenia), and 79 healthy controls. We undertook a detailed investigation into differences in Crus I/II volume using a semi-automated segmentation method optimized for the cerebellum. We analyzed the effects of group and sex, as well as their interaction, on Crus I/II volume in gray matter (GM) and white matter (WM). Results Significant group × sex interactions were found in WM volumes of the bilateral Crus I/II; the UHR males demonstrated significantly larger WM volumes compared to the other male groups, whereas no significant group differences were found in the female groups. Additionally, WM and GM volumes of the Crus I/II had positive associations with symptom severity in the UHR group, whereas, in contrast, GM volumes in the FES group were negatively associated with symptom severity. Conclusions The present findings provide evidence that the morphology of Crus I/II is involved in schizophrenia in a sex- and disease stage-dependent manner. Additionally, alterations of WM volumes of Crus I/II may have potential as a biological marker of early detection and treatment for UHR individuals. This article is protected by copyright. All rights reserved.