Abstract Exposure to low level blast is a common feature of war zone and frequently results in mild TBI in military and civilian personnel. It is unclear however, what parameters of the blast and the magnitude of those parameters are injurious to the human brain. Animal studies suggest that the magnitude of blast overpressure is major component directly related to severity of injury, but the mechanisms of injury are not known. This gap in the knowledge calls for the development of a simplified model that can be used to identify elementary mechanisms responsible for Blast Induced Neurotrauma (BINT). This approach would provide the ability to assess if cavitation is a risk factor of human TBI from the mechanical parameters of a blast insult. It is also of vital importance to understand the relationship between the risk of TBI and relevant outcome measures. The systematic and unbiased investigation of the neurological and pathological disorders emerging as a consequence of the blast exposure requires that the relationship between the blast parameters and the loading to the brain is also known. Currently, there are no reliable or standardized protocols established to test injury mechanisms exclusively related to exposure to pure primary blast. In a series of recently published experimental papers supported by computational models, we laid the foundation for a reliable and repeatable rodent model of blast TBI. Here we propose to use our field verified shock tube to establish a fundamental understanding of cavitation; one of the mechanisms which is believed to cause TBI under primary blast loading conditions. We will simulate the head using surrogate materials-polycarbonate cylinder (skull) and an array of fluids with a wide variation of properties serving as brain model. We will systematically evaluate all relevant parameters causing cavitation under different blast loading conditions: 1) magnitude of blast overpressure and negative phase (under pressure), 2) viscoelastic properties of fluids encased by the surrogate head, 3) the differential of density of fluids inside the shell, and 4) the thickness of the shell (head surrogate). Finally, we will explore if blast related cavitation can occur in two- and multi-phase environment between materials with substantial density difference: the brain and CSF-simulant. In the course of the proposed work, we will develop a quantitative criterion for cavitation under primary shock loads. Pressure and strain measurements and high speed video analysis will be used extensively for this purpose. We will thus gather enough evidence to conclusively state the conditions at which if and when blast related cavitation occurs as an outcome of this research project.
|Effective start/end date||8/13/15 → …|
- U.S. Navy: $417,886.00
Explore the research topics touched on by this project. These labels are generated based on the underlying awards/grants. Together they form a unique fingerprint.