title: Hippocampal subfield volumes in first episode and chronic schizophrenia.
abstract: BACKGROUND
  Reduced hippocampal volume in schizophrenia is a well-replicated finding. New imaging techniques allow delineation of hippocampal subfield volumes. Studies including predominantly chronic patients demonstrate differences between subfields in sensitivity to illness, and in associations with clinical features. We carried out a cross-sectional and longitudinal study of first episode, sub-chronic, and chronic patients, using an imaging strategy that allows for the assessment of multiple hippocampal subfields.
  
  
  METHODS
  Hippocampal subfield volumes were measured in 34 patients with schizophrenia (19 first episode, 6 sub-chronic, 9 chronic) and 15 healthy comparison participants. A subset of 10 first episode and 12 healthy participants were rescanned after six months.
  
  
  RESULTS
  Total left hippocampal volume was smaller in sub-chronic (p = 0.04, effect size 1.12) and chronic (p = 0.009, effect size 1.42) patients compared with healthy volunteers. The CA2-3 subfield volume of chronic patients was significantly decreased (p = 0.009, effect size 1.42) compared to healthy volunteers. The CA4-DG volume was significantly reduced in all three patient groups compared to healthy group (all p < 0.005). The two affected subfield volumes were inversely correlated with severity of negative symptoms (p < 0.05). There was a small, but statistically significant decline in left CA4-DG volume over the first six months of illness (p = 0.01).
  
  
  CONCLUSIONS
  Imaging strategies defining the subfields of the hippocampus may be informative in linking symptoms and structural abnormalities, and in understanding more about progression during the early phases of illness in schizophrenia.
authors: Department of Neuropsychiatry, Kochi Medical School, Kochi, Japan.
authors: Mitsuhiko
authors: M
authors: Kawano
authors: Department of Neuropsychiatry, Kochi Medical School, Kochi, Japan; Department of Psychiatry, Aki General Hospital, Kochi, Japan.
authors: Ken
authors: K
authors: Sawada
authors: Department of Neuropsychiatry, Kochi Medical School, Kochi, Japan.
authors: Shinji
authors: S
authors: Shimodera
authors: Department of Radiology, Hyogo Prefectural Kakogawa Hospital, Hyogo, Japan.
authors: Yasuhiro
authors: Y
authors: Ogawa
authors: Departments of Diagnostic Radiology and Radiation Oncology, Kochi Medical School, Kochi, Japan.
authors: Shinji
authors: S
authors: Kariya
authors: Department of Radiology, University of British Columbia, Vancouver, Canada.
authors: Donna J
authors: DJ
authors: Lang
authors: Department of Neuropsychiatry, Aizu Medical Center, Fukushima Medical University, Fukushima, Japan.
authors: Shimpei
authors: S
authors: Inoue
authors: Department of Psychiatry, University of British Columbia, Vancouver, Canada.
authors: William G
authors: WG
authors: Honer
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D009929:Organ Size; D012559:Schizophrenia / Q000473:pathology*; D055815:Young Adult