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Blunt Trauma of the Aging Eye

Joel D. Stitzel
2005 Archives of Ophthalmology  
Correspondence: Joel D. Stitzel, PhD, Virginia Tech-Wake Forest Center for Injury Biomechanics, Medical Center Blvd, Winston-Salem, NC 27157 (jdstitzel@gmail .com).  ...  Stitzel et al 20 performed a series of eye experiments with foam particles, BBs, and baseballs for validation and development of the Virginia Tech Eye Model (VTEM), a finite-element model used to predict  ...  In the Laboratory Sciences article by Stitzel Table 3 . Line A2 was printed on top of line A1. The table is reproduced correctly as follows. The journal regrets the error.  ... 
doi:10.1001/archopht.123.6.789 pmid:15955980 fatcat:4pt4ehq3yngedjdywxtnai5fsy

Implications of head and neck restraint test repeatability for specification improvement

John P. Patalak, Matthew G. Harper, Joel D. Stitzel
2019 Figshare  
Objective: Since 2005, National Association for Stock Car Auto Racing, Incorporated (NASCAR) drivers have been required to use a head and neck restraint system (HNR) that complies with SFI Foundation, Inc. (SFI) 38.1. The primary purpose of the HNR is to control and limit injurious neck loads and head kinematics during frontal and frontal oblique impacts. The SFI 38.1 performance specification was implemented to establish a uniform test procedure and minimum standard for the evaluation of HNRs
more » ... sing dynamic sled testing. The purpose of this study was to evaluate the repeatability of the current SFI 38.1 test setup and explore the effects of a polyester seat belt restraint system. Method: Eight sled tests were conducted using the SFI 38.1 sled test protocol with additional test setup constraints. Four 0° frontal tests and 4 30° right frontal (RF) oblique tests were conducted. The first 3 tests of each principal direction of force (PDOF) used nylon SFI 16.1 seat belt restraint assemblies. The fourth test of each PDOF used polyester SFI 16.6 seat belt restraint assemblies. A secondary data set (Lab B Data) was also supplied by the HNR manufacturer for further comparisons. The International Organization for Standardization (ISO) 18571 objective comparison method was used to quantify the repeatability of the anthropomorphic test device (ATD) resultant head, chest, and pelvis acceleration and upper neck axial force and flexion extension bending moment time histories across multiple tests. Results: Two data sets generated using the SFI 38.1 test protocol exhibited large variations in mean ISO scores of ATD channels. The 8 tests conducted with additional setup constraints had significantly lower mean ISO score coefficients of variation (CVs). The Lab B tests conducted within the current specification but without the additional test setup constraints had larger mean ISO score standard deviation and CV for all comparisons. Specifically, tests with the additional setup constraints had average CVs of 3.3 [...]
doi:10.6084/m9.figshare.8979812.v1 fatcat:b33rglvp5veydirwdca7wyarim

Special Issue on the NCAA-DoD CARE Consortium Research

Bethany Rowson, Joel D. Stitzel, Stefan M. Duma
2019 Annals of Biomedical Engineering  
doi:10.1007/s10439-019-02379-x pmid:31591661 fatcat:gmffahgdtbd5rcxxdvdds5e3te

Morphometric analysis of variation in the ribs with age and sex

Ashley A. Weaver, Samantha L. Schoell, Joel D. Stitzel
2014 Journal of Anatomy  
Joel Stitzel assisted with study design, acted in an advisory and editorial capacity, and assisted with manuscript preparation.  ...  (d) Resulting configurations of the 20-and 90-year-olds when applying all three Euler angle rotations to the right ninth male rib.  ...  al. 1989; Shorr et al. 1989; Zhou et al. 1996; Perdue et al. 1998; Zioupos & Currey, 1998; Bulger et al. 2000; Bergeron et al. 2003; Holcomb et al. 2003; Stawicki et al. 2004; Hanna & Hershman, 2009; Stitzel  ... 
doi:10.1111/joa.12203 pmid:24917069 fatcat:uyxxuqz3hvfznarcqfopjsddem

Age- and Sex-Specific Thorax Finite Element Model Development and Simulation

Samantha L. Schoell, Ashley A. Weaver, Nicholas A. Vavalle, Joel D. Stitzel
2015 Traffic Injury Prevention  
D Lateral Impact 12.0 F vs. t 70 Male Frontal Hub Impact 6.7 F vs.  ...  Studies have shown that material properties are related to age (Stitzel, Cormier et al. 2003; Kemper, McNally et al. 2005; Kemper, McNally et al. 2007 ).  ... 
doi:10.1080/15389588.2015.1005208 pmid:26027976 fatcat:p3pyf5wo6jcebi2pjqsmlsfeoy

Development of a Computationally Efficient Full Human Body Finite Element Model

Doron Schwartz, Berkan Guleyupoglu, Bharath Koya, Joel D. Stitzel, F. Scott Gayzik
2015 Traffic Injury Prevention  
Moreno 1,2 , Joel D. Stitzel 1,2 , F.  ...  Joel Stitzel and Dr. Ashely Weaver. Dr. Stitzel has provided me with career advice and introduced me to many Biomechanics personnel.  ... 
doi:10.1080/15389588.2015.1021418 pmid:26027975 fatcat:5elbfz7ejrgb7aupcxjxihqjve

Development and validation of an atlas-based finite element brain model

Logan E. Miller, Jillian E. Urban, Joel D. Stitzel
2016 Biomechanics and Modeling in Mechanobiology  
Traumatic brain injury is a leading cause of disability and injury-related death. To enhance our ability to prevent such injuries, brain response can be studied using validated finite element (FE) models. In the current study, a high-resolution, anatomically accurate FE model was developed from the International Consortium for Brain Mapping brain atlas. Due to wide variation in published brain material parameters, optimal brain properties were identified using a technique called Latin hypercube
more » ... sampling, which optimized material properties against three experimental cadaver tests to achieve ideal biomechanics. Additionally, falx pretension and thickness were varied in a lateral impact variation. The atlas-based brain model (ABM) was subjected to the boundary conditions from three high-rate experimental cadaver tests with different material parameter combinations. Local displacements, determined experimentally using neutral density targets, were compared to displacements predicted by the ABM at the same locations. Error between the observed and predicted displacements was quantified using CORrelation and Analysis (CORA), an objective signal rating method that evaluates the correlation of two curves. An average CORA score was computed for each variation and maximized to identify the optimal combination of parameters. The strongest relationships between CORA and material parameters were observed for the shear parameters. Using properties obtained through the described multiobjective optimization, the ABM was validated in three impact configurations and shows good agreement with experimental data. The final model developed in this study consists of optimized brain material properties and was validated in three cadaver impacts against local brain displacement data.
doi:10.1007/s10237-015-0754-1 pmid:26762217 pmcid:PMC4942406 fatcat:4fcxylzp5fgr5bnr5uln6tvwye

Comparing rib cortical thickness measurements from computed tomography (CT) and Micro-CT

Zachary S. Hostetler, Joel D. Stitzel, Ashley A. Weaver
2019 Computers in Biology and Medicine  
Interior (A) and exterior (B) views shown as well as the thickness difference for a 2-D cross section of the clinical-CT with cross-sectional quadrants illustrated (C).  ...  Fig. 2 . 2 Rib specimen segmentation from the 0.50 mm slice thickness clinical-CT (pink) and micro-CT (blue) scans showing the sagittal view (A), axial view (B), and 3-D reconstruction of the micro-CT  ... 
doi:10.1016/j.compbiomed.2019.103330 pmid:31276944 pmcid:PMC6785990 fatcat:a4izga3nlzdorhlftob3rx7u3m

Subconcussive impacts and imaging findings over a season of contact sports

Elizabeth M Davenport, Jillian E Urban, Fatemeh Mokhtari, Ervin L Lowther, John D Van Horn, Christopher G Vaughan, Gerard A Gioia, Christopher T Whitlow, Joel D Stitzel, Joseph A Maldjian
2016 Concussion  
Financial & competing interests disclosure Support for this research was provided by NIH grant NS082453 (JA Maldjian, JD Stitzel), NS088125 (JA Maldjian) and NS091602 (CT Whitlow, JA Maldjian, JD Stitzel  ... 
doi:10.2217/cnc-2016-0003 pmid:30202561 pmcid:PMC6093756 fatcat:gifuchpdpbeondoghy7t4pienm

CT Based Three-Dimensional Measurement of Orbit and Eye Anthropometry

Ashley A. Weaver, Kathryn L. Loftis, Josh C. Tan, Stefan M. Duma, Joel D. Stitzel
2010 Investigative Ophthalmology and Visual Science  
BP ϭ cos Ϫ1 ͩ OH D ͪ (1) RESULTS Select subject demographics and ocular and orbital measurements are reported in Table 1 .  ...  The angle of brow protrusion (BP) was calculated by using equation 1, where OH is the orbital height and D is the distance between the superior and inferior coordinates depicted in Figure 3 .  ... 
doi:10.1167/iovs.10-5503 pmid:20463322 fatcat:hz2h2uspu5d6tbui3k7dubwsji

Validation performance comparison for finite element models of the human brain

Logan E. Miller, Jillian E. Urban, Joel D. Stitzel
2017 Computer Methods in Biomechanics and Biomedical Engineering  
Urban JE, Whitlow CT, Edgerton CA, Powers AK, Maldjian JA, Stitzel JD. Motor vehicle crash- Tse KM, Tan LB, Lee SJ, Lim SP, Lee HP.  ...  Whitlow C, Stitzel J. Investigation of Intraventricular Hemorrhage Volume in Motor Vehicle Crash Occupants. Trauma Cases and Reviews. 2015; 1:021.  ... 
doi:10.1080/10255842.2017.1340462 pmid:28701050 pmcid:PMC5975353 fatcat:ggbvtceamjb7nprb6pna3cdr2a

Motor Vehicle Crash-Related Subdural Hematoma from Real-World Head Impact Data

Jillian E. Urban, Christopher T. Whitlow, Colston A. Edgerton, Alexander K. Powers, Joseph A. Maldjian, Joel D. Stitzel
2012 Journal of Neurotrauma  
(D) Segmentation masks demonstrating volumes of interest (IV mask with SDH mask overlaid). (E) Three-dimensional reconstruction of injury within the intracranial volume.  ... 
doi:10.1089/neu.2012.2373 pmid:22928543 pmcid:PMC3521134 fatcat:26cbw5eqtzh4vl2hpvc7zzbw3q

Characterization of Crash-Induced Thoracic Loading Resulting in Pulmonary Contusion

F Scott Gayzik, R Shayn Martin, H Clay Gabler, J Jason Hoth, Stefan M. Duma, J Wayne Meredith, Joel D. Stitzel
2009 Journal of Trauma  
Pulmonary contusion (PC) is commonly sustained in motor vehicle crash. This study utilizes the Crash Injury Research and Engineering Network (CIREN) database and vehicle crash tests to characterize the occupants and loading characteristics associated with PC. A technique to match CIREN cases to vehicle crash tests is applied to quantify the thoracic loading associated with this injury. Methods: The CIREN database and crash test data from the National Highway Traffic Safety Administration were
more » ... ed in this study. An analysis of CIREN data were conducted between three study cohorts: patients that sustained PC and any other chest injury (PC؉ and chest؉), patients with chest injury and an absence of PC (PC؊ and chest؉), and a control group without chest injury and an absence of PC (PC؊ and chest؊). Forty-one lat-eral impact crash tests were analyzed and thoracic loading data from onboard crash tests dummies were collected. Results: The incidence of PC in CIREN data were 21.7%. Crashes resulting in PC demonstrated significantly greater mortality (23.9%) and Injury Severity Score (33.1 ؎ 15.7) than the control group. The portion of lateral impacts increased from 27% to 48% between the control group and PC؉ and chest؉ cohort, prompting the use of lateral impact crash tests for the case-matching portion of the study. Crash tests were analyzed in two configurations; vehicle-to-vehicle tests and vehicle-to-pole tests. The average maximum chest compression and deflection velocity from the dummy occupants were found to be 25.3% ؎ 2.6% and 4.6 m/s ؎ 0.42 m/s for the vehicle-to-pole tests and 23.0% ؎ 4.8% and 3.9 m/s ؎ 1.1 m/s for the vehicle-to-vehicle tests. Chest deflection versus time followed a roughly symmetric and sinusoidal profile. Sixteen CIREN cases were identified that matched the vehicle crash tests. Of the 16 matched cases, 12 (75%) sustained chest injuries, with half of these patients presenting with PC. Conclusions: Quantified loading at the chest wall indicative of PC and chest injury in motor vehicle crash is valuable boundary condition data for bench-top studies or computer simulations focused on this injury. In addition, because PC often exhibits a delayed onset, knowing the population and crash modes highly associated with this injury may promote earlier detection and improved management of this injury.
doi:10.1097/ta.0b013e318186251e pmid:19276763 fatcat:wkoeyaptk5aoxo3ya7xgfck7q4

An experimental and computational study of blunt carotid artery injury

F Scott Gayzik, Ola Bostrom, Per Ortenwall, Stefan M Duma, Joel D Stitzel
2006 Annual proceedings. Association for the Advancement of Automotive Medicine  
. 2005) , aorta (Shah, Yang et al. 2001; Richens, Field et al. 2004) , eye (Stitzel, Duma et al. 2002) and abdomen (Lee and Yang 2001) .  ...  Recent research has focused on modeling injuries to specific soft tissue organs in the body including the brain (Zhang, Yang et al. 2001; Takhounts, Eppinger et al. 2003) , lung (Stitzel, Gayzik et al  ... 
pmid:16968627 pmcid:PMC3217480 fatcat:7l4rz3v5l5hvdcduwddrk56ofa

Investigation of the Mass Distribution of a Detailed Seated Male Finite Element Model

Nicholas A. Vavalle, A. Bradley Thompson, Ashley R. Hayes, Daniel P. Moreno, Joel D. Stitzel, F. Scott Gayzik
2014 Journal of Applied Biomechanics  
Accurate mass distribution in computational human body models is essential for proper kinematic and kinetic simulations. The purpose of this study was to investigate the mass distribution of a 50 th percentile male (M50) full body finite element model (FEM) in the seated position. The FEM was partitioned into 10 segments, using segment planes constructed from bony landmarks per the methods described in previous research studies. Body segment masses and centers of gravity (CGs) of the FEM were
more » ... mpared to values found from these studies, which unlike the present work assumed homogeneous body density. Segment masses compared well to literature while CGs showed an average deviation of 6.0% to 7.0% when normalized by regional characteristic lengths. The discrete mass distribution of the FEM appears to affect the mass and CGs of some segments, particularly those with low density soft tissues. The locations of the segment CGs are provided in local coordinate systems, thus facilitating comparison to other full body FEMs and human surrogates. The model provides insights into the effects of inhomogeneous mass on the location of body segment CGs.
doi:10.1123/jab.2013-0007 pmid:24345784 fatcat:gs7xcjn2anapjasbqah7puxstu
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