A magnetic resonance imaging study of the entorhinal cortex in treatment-resistant depression.
Despite a growing interest in this area, we continue to lack an understanding of the pathophysiology of depression and of treatment-resistant depression (TRD) in particular. The role of the medial temporal lobe, particularly the hippocampus, has been widely implicated in the aetiology of depression. However, related structures such as the entorhinal cortex have not been systematically examined. This research study aimed to examine possible abnormalities in the volume of the entorhinal cortex (ERC) in TRD patients. A group of 45 TRD patients and 30 healthy age- and sex-matched controls underwent magnetic resonance imaging (MRI). ERC volumes were manually traced from MRI data using ANALYZE software. An analysis of variance was conducted between subject groups and in the sexes separately while controlling for the effects of brain size via intracranial volume (ICV). Results revealed significant reductions in the volume of the left ERC of female patients. Although preliminary, our findings suggest that anatomical abnormalities in the ERC may confer vulnerability to treatment resistance. Confirmatory longitudinal studies are required to determine whether these abnormalities predate the onset of depression or are the result of a more chronic, treatment-resistant course of illness.
Alfred Psychiatry Research Centre, The Alfred and Monash University School of Psychology, Psychiatry and Psychological Medicine, Melbourne, Victoria 3004, Australia.
Christina P
CP
Furtado
Jerome J
JJ
Maller
Paul B
PB
Fitzgerald
D000328:Adult; D000928:Antidepressive Agents / Q000627:therapeutic use*; D001284:Atrophy; D001921:Brain / Q000473:pathology; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology* / Q000523:psychology; D004292:Dominance, Cerebral / Q000502:physiology; D004351:Drug Resistance; D018728:Entorhinal Cortex / Q000473:pathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012737:Sex Factors
D000928:Antidepressive Agents