Citation

Pieper J, Chang DG, Mahasin SZ, Swan AR, Quinto AA, Nichols SL, Diwakar M, Huang C, Swan J, Lee RR, Baker DG, Huang M. J. Head Trauma Rehabil. 2019; ePub(ePub): ePub.

Affiliation

Department of Physical Medicine and Rehabilitation University of Michigan, Ann Arbor, Michigan (Dr Pieper), Departments of Orthopaedic Surgery (Dr Chang), Radiology, Research, and Psychiatry Services (Mss Swan and Quinto and Drs Lee, Baker, and M. Huang), Radiology (Mss Swan and Quinto and Drs Lee and M. Huang), Neurosciences (Dr Nichols), and Psychiatry (Dr Baker), University of California, San Diego; College of Medicine, King Saud University, Riyadh, Saudi Arabia (Ms Mahasin); Department of Radiology and Biomedical Imaging, University of California, San Francisco (Dr Diwakar); Department of Bioengineering, Stanford University, Stanford, California (Mr C. Huang); Department of Management Information Systems, San Diego State University, San Diego, California (Mr Swan); and VA Center of Excellence for Stress and Mental Health, San Diego, California (Dr Baker).

Copyright

(Copyright © 2019, Lippincott Williams and Wilkins)

DOI

10.1097/HTR.0000000000000492

PMID

31033749

Abstract

OBJECTIVE: To identify amygdalar volumetric differences associated with posttraumatic stress disorder (PTSD) in individuals with comorbid mild traumatic brain injury (mTBI) compared with those with mTBI-only and to examine the effects of intracranial volume (ICV) on amygdala volumetric measures. SETTING: Marine Corps Base and VA Healthcare System. PARTICIPANTS: A cohort of veterans and active-duty military personnel with combat-related mTBI (N = 89).

DESIGN: Twenty-nine participants were identified with comorbid PTSD and mTBI. The remaining 60 formed the mTBI-only control group. Structural images of brains were obtained with a 1.5-T MRI scanner using a T1-weighted 3D-IR-FSPGR pulse sequence. Automatic segmentation was performed in Freesurfer. MAIN MEASURES: Amygdala volumes with/without normalizations to ICV.

RESULTS: The comorbid mTBI/PTSD group had significantly larger amygdala volumes, when normalized to ICV, compared with the mTBI-only group. The right and left amygdala volumes after normalization to ICV were 0.122% ± 0.012% and 0.118% ± 0.011%, respectively, in the comorbid group compared with 0.115% ± 0.012% and 0.112% ± 0.009%, respectively, in the mTBI-only group (corrected P <.05).

CONCLUSIONS: The ICV normalization analysis performed here may resolve previous literature discrepancies. This is an intriguing structural finding, given the role of the amygdala in the challenging neuroemotive symptoms witnessed in casualties of combat-related mTBI and PTSD.

Language: en