48 echo T2 myelin imaging of white matter in first-episode schizophrenia: Evidence for aberrant myelination

Abstract

Myelin water imaging provides a novel strategy to assess myelin integrity and corresponding clinical relationships in psychosis, of particular relevance in frontal white matter regions. In the current study, T2 myelin water imaging was used to assess the myelin water fraction (MWF) signal from frontal areas in a sample of 58 individuals experiencing first-episode psychosis (FEP) and 44 healthy volunteers. No differences in frontal MWF were observed between FEP subjects and healthy volunteers; however, differences in normal patterns of associations between frontal MWF and age, education and IQ were seen. Significant positive relationships between frontal MWF and age, North American Adult Reading Test (NAART) IQ, and years of completed education were observed in healthy volunteers. In contrast, only the relationship between frontal MWF and NAART IQ was significant after Bonferroni correction in the FEP group. Additionally, significant positive relationships between age and MWF in the anterior and posterior internal capsules, the genu, and the splenium were observed in healthy volunteers. In FEP subjects, only the relationship between age and MWF in the splenium was statistically significant. Frontal MWF was not associated with local white matter volume. Altered patterns of association between age, years of education, and MWF in FEP suggest that subtle disturbances in myelination may be present early in the course of psychosis.

Keywords

• Myelin water fraction
• First-episode psychosis
• Schizophrenia
• Frontal white matter