An MRI study of septi pellucidi in relation to hippocampus volume and fornix integrity in schizophrenia.

Septum pellucidum (SP) and cavum SP (CSP) were delineated in two samples. The Longitudinal Study examined structural MR-images in first-episode schizophrenia (FESZ) and controls at two time-points. The Cross-Sectional Study examined structural and diffusion-tensor MR measures, including hippocampus and fornix, in chronic schizophrenia (SZ) at one time-point. CSP and SP measurements remained stable over time in FESZ and controls. Compared to controls, CSP were smaller in FESZ, but not in chronic SZ. SP were larger in chronic SZ, but not in FESZ. In chronic SZ only, SP-Length was correlated negatively with fornix-FA and hippocampal volume, and positively with chlorpromazine-equivalent dosage.