Co-Occurrence of Large Cavum Septum Pellucidum and the Absence of the Adhesio Interthalamica in Patients with Schizophrenia: A Post Mortem Study

Despite considerable efforts to identify neuroanatomical markers of disturbed midline structure development in patients with schizophrenia, results have been mixed. There remains a great deal of debate as to whether patients with schizophrenia exhibit a higher prevalence of cavum septi pellucidi (CSP) than healthy controls and as to whether an absence of ahesio interthalamica (AI) is evident in most patients. Inconsistent findings may be due to differences in methodology, in the criteria for CSP or the small sample size of previous studies. We investigated the prevalence of these two neuroanatomical markers, large CSP (>6mm in length) and a noted absence of AI, in postmortem brain specimens collected from 479 autopsied cadavers (64.7% male). Main inclusion criteria included an absence of macroscopic changes on brain parenchyma and a post mortem interval within 12 hours after death. The overall prevalence of an absent AI was 14.82%. Among those within the sample with a diagnosis of schizophrenia (25 subjects) the prevalence of AI absence was 22.22%. Isolated analysis for AI absence did not discriminate patients with schizophrenia from healthy individuals or from other patient subgroups with detectable CSP. While neither the presence of larger CSP nor the absence of AI alone could distinguish patients with schizophrenia from health controls, in combination these markers differentiated symptomatic individuals from healthy subjects and from symptomatic patients with small CSP (<6mm). These findings suggest that when considered collectively, these two abnormalities may represent an important neuroanatomical marker of midline abnormalities in schizophrenia. However, further studies are needed to understand the developmental stage at which these changes occur and to better understand how these disturbances relate to the clinical symptoms of schizophrenia.