title: White Matter Abnormalities in Post-traumatic Stress Disorder Following a Specific Traumatic Event.
abstract: Studies of posttraumatic stress disorder (PTSD) are complicated by wide variability in the intensity and duration of prior stressors in patient participants, secondary effects of chronic psychiatric illness, and a variable history of treatment with psychiatric medications. In magnetic resonance imaging (MRI) studies, patient samples have often been small, and they were not often compared to similarly stressed patients without PTSD in order to control for general stress effects. Findings from these studies have been inconsistent. The present study investigated whole-brain microstructural alterations of white matter in a large drug-naive population who survived a specific, severe traumatic event (a major 8.0-magnitude earthquake). Using diffusion tensor imaging (DTI), we explored group differences between 88 PTSD patients and 91 matched traumatized non-PTSD controls in fractional anisotropy (FA), as well as its component elements axial diffusivity (AD) and radial diffusivity (RD), and examined these findings in relation to findings from deterministic DTI tractography. Relations between white matter alterations and psychiatric symptom severity were examined. PTSD patients, relative to similarly stressed controls, showed an FA increase as well as AD and RD changes in the white matter beneath left dorsolateral prefrontal cortex and forceps major. The observation of increased FA in the PTSD group suggests that the pathophysiology of PTSD after a specific acute traumatic event is distinct from what has been reported in patients with several years duration of illness. Alterations in dorsolateral prefrontal cortex may be an important aspect of illness pathophysiology, possibly via the region's established role in fear extinction circuitry. Use-dependent myelination or other secondary compensatory changes in response to heightened demands for threat appraisal and emotion regulation may be involved.
authors.affiliation: Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Li
authors.affiliation: Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, China.
authors.forename: Du
authors.initials: D
authors.lastname: Lei
authors.affiliation: Mental Health Institute, The Second Xiangya Hospital of Central South University, Changsha, China.
authors.forename: Lingjiang
authors.initials: L
authors.lastname: Li
authors.affiliation: Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, China.
authors.forename: Xiaoqi
authors.initials: X
authors.lastname: Huang
authors.affiliation: Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, China.
authors.forename: Xueling
authors.initials: X
authors.lastname: Suo
authors.affiliation: Department of Neurology, West China Hospital of Sichuan University, Chengdu, China; Department of Psychiatry, West China Hospital of Sichuan University, Chengdu, China; Department of Oncology, State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, China.
authors.forename: Fenglai
authors.initials: F
authors.lastname: Xiao
authors.affiliation: Department of Neurology, West China Hospital of Sichuan University, Chengdu, China; Department of Psychiatry, West China Hospital of Sichuan University, Chengdu, China; Department of Oncology, State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, China.
authors.forename: Weihong
authors.initials: W
authors.lastname: Kuang
authors.affiliation: Department of Neurology, West China Hospital of Sichuan University, Chengdu, China; Department of Psychiatry, West China Hospital of Sichuan University, Chengdu, China; Department of Oncology, State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Neurology, West China Hospital of Sichuan University, Chengdu, China; Department of Psychiatry, West China Hospital of Sichuan University, Chengdu, China; Department of Oncology, State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Bi
authors.affiliation: Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, China.
authors.forename: Su
authors.initials: S
authors.lastname: Lui
authors.affiliation: Magnetic Resonance and Image Analysis Research Centre and Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, England, UK.
authors.forename: Graham J
authors.initials: GJ
authors.lastname: Kemp
authors.affiliation: Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, China; University of Texas Southwestern, Dallas, USA.
authors.forename: John A
authors.initials: JA
authors.lastname: Sweeney
authors.affiliation: Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, China.
authors.forename: Qiyong
authors.initials: Q
authors.lastname: Gong
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D056324:Diffusion Tensor Imaging; D055866:Earthquakes; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D013313:Stress Disorders, Post-Traumatic / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology*; D066127:White Matter / Q000473:pathology*
keywords: Diffusion tensor imaging; Magnetic resonance imaging; Mental disorders; Neuroimaging; Posttraumatic stress disorder; Psychoradiology