According to the US Defense and Veterans Brain Injury Center (DVBIC) and Centers for Disease Control and Prevention (CDC), mild traumatic brain injury (mTBI) is a common form of head injury. Medical imaging data provides clinical insight into tissue damage/injury and injury severity, and helps medical diagnosis. Computational modeling and simulation can predict the biomechanical characteristics of such injury, and are useful for development of protective equipment. Integration of techniques from computational biomechanics with medical data assessment modalities (e.g., magnetic resonance imaging or MRI) has not yet been used to predict injury, support early medical diagnosis, or assess effectiveness of personal protective equipment.This work&nbsp;presents a methodology to map computational simulations with clinical data for interpreting blunt impact TBI utilizing two clinically different head injury case studies. MRI modalities, such as T1, T2, diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC), were used for simulation comparisons. The two clinical cases have been reconstructed using finite element analysis to predict head biomechanics based on medical reports documented by a clinician. The findings are mapped to simulation results using image-based clinical analyses of head impact injuries, and modalities that could capture simulation results have been identified. Biomechanical parameters such as pressure, shear stress, principal strain, strain rate, product of strain and strain rate, and strain energy were considered to quantitatively compare biomechanical simulations with clinical assessments. Based on the simulation result analysis, we found different biomechanical measures to explain different blunt impact injury modalities. The minimum pressure (i.e., maximum tensile pressure) and maximum strain rate in brain tissue were seen to best represent tissue damage/injury identified by in vivo ADC values from MRI analysis. Specifically, for case 1, a blunt impact with a small solid object resulting in an indented skull, the ADC contours of contusion corresponded well with those for effective strain rates higher than 250 s−1. For case 2, a blunt impact with a larger solid object producing a coup–contrecoup injury and no noticeable skull indentation, the ADC contours showing contusion and edema mapped well with a negative pressure of -90 kPa or more.The methodology comparing biomechanical simulations with ADC from image-based clinical analysis presented here can lead to a future roadmap to understand and interpret injury criteria, and to improve accuracy in biomechanical prediction. As the findings are substantiated with additional clinical studies, it can be broadly applied as a tool to support injury assessment in head trauma events due to blunt and blast loadings and to improve countermeasures (e.g., diagnostics and protective equipment design) to mitigate these injuries.

A Methodology to Compare Biomechanical Simulations With Clinical Brain Imaging Analysis Utilizing Two Blunt Impact Cases

Paper Proceedings: https://asmedigitalcollection.asme.org/IMECE/IMECE2021/volume/85543

ASME 2021 International Mechanical Engineering Congress and Exposition (IMECE2021)

Supporting the need among researchers worldwide for additional online and multimedia content, ASME now offers the ASME Conference Video Collection. This platform will collect and provide long-term access to conference presentation videos, encompassing all technology areas within ASME's technical conference and events program. About 30,000-40,000 engineers across all mechanical engineering and related disciplines participate in ASME conferences each year. This includes authors of approximately 6,000 to 8,000 technical papers published by ASME, the majority of whom also submit video presentations for our virtual conferences. The video collection will be available as an add-on to existing product packages or as a separate subscription.