Experimental and Computational Investigation of Correlates of Diffusion Tensor Imaging Changes and Mechanical Strain
Open Access
- Author:
- Aklilu, Ouniol
- Millennium Scholars Program:
- Biomedical Engineering (BME)
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisor:
- Reuben H Kraft, Thesis Supervisor
Justin Lee Brown, Honors Advisor
Nanyin Zhang, Advisor - Keywords:
- Traumatic Brain Injury
Fractional Anisotropy
White Matter Tissue - Abstract:
- Traumatic brain injury (TBI) and related disability affects more than 2% of the U.S. population.1 Diffuse axonal injury (DAI) is a common pathology associated with TBI in which deformation of axonal cells leads to rupture and axonal degeneration.2 DAI can be observed in white matter tissue in the brain,3 which consists largely of bundles of aligned, myelin-sheathed axons. State-of-the-art imaging techniques (magnetic resonance diffusion tensor imaging, or MR-DTI) can be used to visualize these fibrous structures. However, sensitive measures of structural changes due to injury that can be detected with MR-DTI, notably fractional anisotropy (FA), show conflicting trends in how FA changes in response to injury. Some studies have shown FA values increase within brain fibers inflicted by compressive forces while other studies exhibit increase of FA inside the brain fibers due to tensile force.4,5 To better understand how injuries such as TBI affect the brain, computational and experimental investigation was conducted on phantom fibers, a polyester fiber that mimics the white matter of the brain, to learn the impact strain has on fibers and how the FA values changes in response. The hypothesis is that areas of tensile strain will depict increased values of FA while areas of compressive strain depict decreased values of FA. The results from this work will help develop a computational tool that will predict the primary and secondary effects of axonal injury over time and expand the capabilities in the emerging field of computational medicine.