Radiological-Pathological Correlations Following Blast-Related Traumatic Brain Injury in the Whole Human Brain Using ex Vivo Diffusion Tensor Imaging.

摘要

The objective of the project is to perform anatomically correlated high resolution DTI studies and quantitative immunohistochemical analyses of axonal injury in the human brain following traumatic brain injury. The specific aims are Aim (1) To optimize the resolution and signal quality of whole human brain ex vivo diffusion tensor imaging; Aim (2) To perform radiological- pathological correlations using whole human brains from civilian TBI fatalities and US military fatalities caused by blast-related injuries. Aim (3) To construct detailed atlases of the brain regions most frequently injured by blast-related TBI and non-blast-related TBI. During the third year of the project, we have made progress as follows: (A) We have performed DTI on 59 blocks of brain tissue: 2-3 regions from each of 22 cases (5 blast-TBI, 8 non- blast TBI, 9 controls); (B) We have performed blinded stereological analysis of axonal injury, microgliosis and astrogliosis in each of the 63 blocks of tissue; (C) We found essentially no correlation between any of the DTI parameters and the histopathological markers. Possible explanations for this lack of correlation include heterogenous brain white matter fiber orientation, high variability in injury to death interval, and inconsistent brain tissue fixation. Ongoing work will address these possibilities.