Anterior and posterior hippocampal volumes in schizophrenia

Abstract

Background While the evidence for hippocampal structural abnormalities in schizophrenia is now well accepted, whether there is differentially greater volume loss within specific subregions of the hippocampus remains a matter of some debate. Here we present volume estimates of anterior and posterior hippocampal volumes using a novel morphometric protocol. Methods We studied 25 male patients with schizophrenia and 25 age-matched male control subjects. Hippocampal volumes were estimated using a three-dimensional morphometric protocol for the analysis of high-resolution structural magnetic resonance images (MRI). Anterior hippocampal volumes were differentiated from posterior hippocampal volumes by the presence of the uncus in coronal slices. Results While the patients with schizophrenia had significantly smaller overall hippocampal volumes relative to the control group, there was no evidence for a topographically specific pattern of volume loss along the anterior–posterior hippocampal axis. Conclusions These results confirm the presence of overall hippocampal volume decreases in patients with schizophrenia, but do not confirm a topographically specific localization of this effect. It appears that the hippocampal volume deficit in schizophrenia is diffuse, a finding that has important consequences for understanding the underlying pathophysiologic mechanisms in schizophrenia.