Brenda Bartnik Olson1, Kimberly Conley2, Karen Tong1, Sarah Uffindell3, Valerie Wong4, Barbara Holshouser1
1Dept. of Radiology, Loma Linda University, Loma Linda, CA, United States; 2School of Medicine, Loma Linda University, Loma Linda, CA, United States; 3Dept. of Neurology, Loma Linda University, Loma Linda, CA, United States; 4Redlands Pediatric and Adult Medicine, Loma Linda University, Loma Linda, CA, United States
Neurocognitive deficits occur in approximately 50-80% of mild TBI patients, which may persist for several years after injury even though conventional imaging is normal. In this study we used diffusion tensor and 1H magnetic resonance spectroscopic imaging to evaluate if microstructural and/or metabolic abnormalities are present in mTBI subjects with persistent neurocognitive deficits. Our findings show that regions of neuronal loss or dysfunction are present in the left anterior internal capsule and left occipital white matter of mild TBI patients. In addition, increased fractional anisotropy in the left anterior internal capsule may be related to an increase in extracellular space adjacent to remaining axons after the loss of a subset of corticospinal tract fibers. Our findings suggest that both metabolic and ultrastructural changes persist following a mild TBI which may relate to continued neurocognitive deficits seen in these subjects.