Magnetic resonance imaging of hippocampal subfields in posttraumatic stress disorder.
BACKGROUND
Most neuroimaging studies of posttraumatic stress disorder (PTSD) have focused on potential abnormalities in the whole hippocampus, but the subfields of this structure, which have distinctive histological characteristics and specialized functions, have not been investigated. Studies of individual subfields may clarify the role of the hippocampus in PTSD.


OBJECTIVE
To determine if PTSD is associated with structural alterations in specific subfields of the hippocampus.


METHODS
Case-control study.


METHODS
A total of 17 male veterans with combat trauma and PTSD (mean [SD] age, 41 [12] years) and 19 age-matched male veterans without PTSD who were recruited from the outpatient mental health clinic of the San Francisco Veterans Affairs Medical Center and by advertising in the community.


METHODS
High-resolution magnetic resonance imaging at 4 T.


METHODS
Volumes of hippocampal subfields.


RESULTS
Posttraumatic stress disorder was associated with 11.4% (1.5%) (P = .02) smaller mean (SD) cornu ammonis 3 (CA3)/dentate gyrus subfield volumes, irrespective of age-related alterations, whereas other subfields were spared. Age was associated with reduced volume of the CA1 subfield (P = .03). Total hippocampal volume was also reduced in PTSD by a mean (SD) of 6.5% (0.6%) but, related to both PTSD (P = .05) and age (P = .01), was consistent with the measurements in the subfields.


CONCLUSIONS
The findings indicate for the first time in humans that PTSD is associated with selective volume loss of the CA3/dentate gyrus subfields, consistent with animal studies, implying that chronic stress suppresses neurogenesis and dendritic branching in these structures.
Wang
Zhen
Z
Shanghai Mental Heath Center, Shanghai Jiao Tong University, School of Medicine, Shanghai, China.
Neylan
Thomas C
TC
Mueller
Susanne G
SG
Lenoci
Maryann
M
Truran
Diana
D
Marmar
Charles R
CR
Weiner
Michael W
MW
Schuff
Norbert
N
D000328:Adult; D000367:Age Factors; D001284:Atrophy / Q000473:pathology; D056654:CA3 Region, Hippocampal / Q000473:pathology; D016022:Case-Control Studies; D003713:Dendritic Cells / Q000502:physiology; D018891:Dentate Gyrus / Q000473:pathology; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods / Q000706:statistics & numerical data*; D008297:Male; D055495:Neurogenesis / Q000502:physiology; D013313:Stress Disorders, Post-Traumatic / Q000175:diagnosis / Q000473:pathology*; D014728:Veterans / Q000523:psychology / Q000706:statistics & numerical data