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Finite Element Modeling of the Human Head

01 Jan 2000-
TL;DR: In this paper, the authors defined the dimension of head injuries in Sweden over a longer period and presented a finite element (FE) model of the human head which can be used to diagnose head injuries.
Abstract: The main objectives of the present thesis were to define the dimension of head injuries in Sweden over a longer period and to present a Finite Element (FE) model of the human head which can be used ...

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Citations
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Proceedings ArticleDOI
TL;DR: It was found that a simple linear combination of peak change in rotational velocity and HIC showed a high correlation with the maximum principal strain in the brain, in addition to being a significant predictor of injury.
Abstract: The aim of this study is to evaluate all the 58 available NFL cases and compare various predictors for mild traumatic brain injuries using a detailed and extensively validated finite element model of the human head. Global injury measures such as magnitude in angular and translational acceleration, change in angular velocity, head impact power (HIP) and HIC were also investigated with regard to their ability to predict the intracranial pressure and strains associated with injury. The brain material properties were modeled using a hyperelastic and viscoelastic constitutive law. Also, three different stiffness parameters, encompassing a range of published brain tissue properties, were tested. 8 tissue injury predictors were evaluated for 6 different regions, covering the entire cerebrum, as well as for the whole brain. In addition, 10 head kinematics based predictors were evaluated both for correlation with injury as well as with strain and pressure. When evaluating the results, a statistical correlation between strain, strain rate, product of strain and strain rate, Cumulative Strain Damage Measure (CSDM), strain energy density, maximum pressure, magnitude of minimum pressure, as well as von Mises effective stress, with injury was found when looking into specific regions of the brain. However, the maximal pressure in the gray matter showed a higher correlation with injury than other evaluated measures. On the other hand, it was possible, through the reconstruction of a motocross accident, to re-create the injury pattern in the brain of the injured rider using maximal principal strain. It was also found that a simple linear combination of peak change in rotational velocity and HIC showed a high correlation (R=0.98) with the maximum principal strain in the brain, in addition to being a significant predictor of injury. When applying the rotational and translational kinematics separately for one of the cases, it was found that the translational kinematics contribute very little to the intracranial distortional strains while the rotational kinematics contributes insignificantly to the pressure response. This study underlines that the strain based brain tissue injury predictors are very sensitive to the choice of stiffness for the brain tissue.

617 citations


Cites result from "Finite Element Modeling of the Huma..."

  • ...The details of this accident reconstruction are described in Kleiven (2006c) and Kleiven and von Holst (2007)....

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  • ...This is contrary to a previous study using the same model (Kleiven, 2006a), as well as to the hypothesis of Holbourn (1943). This could be due to the above mentioned uncertainties in input kinematics or due to the particular model response for this input....

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Journal ArticleDOI
TL;DR: The model predicts that ONH biomechanics are strongly dependent on sCleral biomechanical properties, and suggests that interindividual variations in scleral properties could be a risk factor for the development of glaucoma.
Abstract: measures. RESULTS. The five input factors that had the largest influence across all outcome measures were, in ranked order: stiffness of the sclera, radius of the eye, stiffness of the lamina cribrosa, IOP, and thickness of the scleral shell. The five least influential factors were, in reverse ranked order: retinal thickness, peripapillary rim height, cup depth, cup-to-disc ratio, and pial thickness. Factor ranks were similar for various outcome measure groups and factor ranges. CONCLUSIONS. The model predicts that ONH biomechanics are strongly dependent on scleral biomechanical properties. Acute deformations of ONH tissues, and the consequent high levels of neural tissue strain, were less strongly dependent on the action of IOP directly on the internal surface of the ONH than on the indirect effects of IOP on the sclera. This suggests that interindividual variations in scleral properties could be a risk factor for the development of glaucoma. Eye size and lamina cribrosa biomechanical properties also have a strong influence on ONH biomechanics. (Invest Ophthalmol Vis Sci. 2005;46: 4189‐4199) DOI:10.1167/iovs.05-0541

475 citations

Journal ArticleDOI
TL;DR: Computed levels of strain in the lamina cribrosa are biologically significant and capable of contributing to the development of glaucomatous optic neuropathy, even without considering the probable accentuating effect of the lAMA's microarchitecture.
Abstract: METHODS. Several models of the optic nerve head tissues (preand postlaminar neural tissue, lamina cribrosa, central retinal vessel, sclera, and pia mater) were constructed. Stresses, deformations, and strains were computed using finite element modeling for a range of normal and elevated intraocular pressures. Computed retinal surface deformations were compared with measured deformation patterns in enucleated human eyes. A sensitivity analysis was performed in which tissue properties and selected geometric features were varied. RESULTS. Acute IOP-induced deformation of the vitreoretinal interface was highly dependent on optic cup shape but showed a characteristic “W-shaped” profile that did not match the deformation of the anterior surface of the lamina cribrosa. The central retinal vasculature had surprisingly little effect on optic nerve head biomechanics. At an IOP of 50 mm Hg, strains (fractional elongation) in the lamina cribrosa averaged 4% to 5.5%, dependent on model geometry, with maximum strains up to 7.7%. Strains in the lamina cribrosa were more dependent on scleral stiffness, scleral thickness, and scleral canal diameter than on lamina cribrosa stiffness and optic cup shape. CONCLUSIONS. Computed levels of strain in the lamina cribrosa are biologically significant and capable of contributing to the development of glaucomatous optic neuropathy, even without considering the probable accentuating effect of the lamina cribrosa’s microarchitecture. Depending on optic cup shape, IOP-induced deformation of the vitreoretinal interface may not match lamina cribrosa deformation. This finding implies that scanning laser tomography has limited ability to estimate lamina cribrosa deformation when imaging the anterior topography of the optic nerve head. Biomechanical effects in the lamina cribrosa depend strongly on scleral properties. (Invest Ophthalmol Vis Sci. 2004;45:4378‐4387) DOI:10.1167/ iovs.04-0133

307 citations


Cites background from "Finite Element Modeling of the Huma..."

  • ...* As cited by Kleiven.(41) 4380 Sigal et al....

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Journal ArticleDOI
TL;DR: A transversely isotropic hyperelastic model recently proposed by Meaney (2003) is adopted and mathematically studied under uniaxial loading conditions to study the effect of the heterogeneity in the tensile/compressive response on the material parameters.
Abstract: The present study deals with the experimental analysis and mechanical modeling of tensile behavior of brain soft tissue. A transversely isotropic hyperelastic model recently proposed by Meaney (2003) is adopted and mathematically studied under uniaxial loading conditions. Material parameter estimates are obtained through tensile tests on porcine brain materials accounting for regional and directional differences. Attention is focused on the short-term response. An extrapolation of tensile test data to the compression range is performed theoretically, to study the effect of the heterogeneity in the tensile/compressive response on the material parameters. Experimental and numerical results highlight the sensitivity of the adopted model to the test direction.

229 citations


Cites background or methods from "Finite Element Modeling of the Huma..."

  • ...2004); and formulation of detailed finite element models of the human head (see Huang et al. 1999, 2000; Zhang et al. 2001; Kleiven 2002; Mota et al. 2003)....

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  • ...…2004); definition of automatic procedures for brain topology reconstruction from image data (cf., Bartesaghi and Sapiro 2001; Ramon et al. 2004); and formulation of detailed finite element models of the human head (see Huang et al. 1999, 2000; Zhang et al. 2001; Kleiven 2002; Mota et al. 2003)....

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Journal ArticleDOI
TL;DR: The results indicate that, despite the fundamental differences between these six model formulations, the comparisons with the experimentally measured pressures and relative displacements were largely consistent and in good agreement and may prove useful for those attempting to model real life accident scenarios.
Abstract: In order to create a useful computational tool that will aid in the understanding and perhaps prevention of head injury, it is important to know the quantitative influence of the constitutive properties, geometry and model formulations of the intracranial contents upon the mechanics of a head impact event. The University College Dublin Brain Trauma Model (UCDBTM) [1] has been refined and validated against a series of cadaver tests and the influence of different model formulations has been investigated. In total six different model configurations were constructed: (i) the baseline model, (ii) a refined baseline model which explicitly differentiates between grey and white neural tissue, (iii) a model with three elements through the thickness of the cerebrospinal fluid (CSF) layer, (iv) a model simulating a sliding boundary, (v) a projection mesh model (which also distinguishes between neural tissue) and (vi) a morphed model. These models have been compared against cadaver tests of Trosseille [2] an...

216 citations

References
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Book
26 Jun 1995
TL;DR: The Finite Element Method as mentioned in this paper is a method for linear analysis in solid and structural mechanics, and it has been used in many applications, such as heat transfer, field problems, and Incompressible Fluid Flows.
Abstract: 1. An Introduction to the Use of Finite Element Procedures. 2. Vectors, Matrices and Tensors. 3. Some Basic Concepts of Engineering Analysis and an Introduction to the Finite Element Methods. 4. Formulation of the Finite Element Method -- Linear Analysis in Solid and Structural Mechanics. 5. Formulation and Calculation of Isoparametric Finite Element Matrices. 6. Finite Element Nonlinear Analysis in Solid and Structural Mechanics. 7. Finite Element Analysis of Heat Transfer, Field Problems, and Incompressible Fluid Flows. 8. Solution of Equilibrium Equations in State Analysis. 9. Solution of Equilibrium Equations in Dynamic Analysis. 10. Preliminaries to the Solution of Eigenproblems. 11. Solution Methods for Eigenproblems. 12. Implementation of the Finite Element Method. References. Index.

8,068 citations

Book
12 Sep 2000
TL;DR: In this paper, the authors present a list of boxes for Lagrangian and Eulerian Finite Elements in One Dimension (LDF) in one dimension, including Beams and Shells.
Abstract: Preface. List of Boxes. Introduction. Lagrangian and Eulerian Finite Elements in One Dimension. Continuum Mechanics. Lagrangian Meshes. Constitutive Models Solution Methods and Stability. Arbitrary Lagrangian Eulerian Formulations. Element Technology. Beams and Shells. Contact--Impact. Appendix 1: Voigt Notation. Appendix 2: Norms. Appendix 3: Element Shape Functions. Glossary. References. Index.

3,928 citations

Book
01 Jan 1984
TL;DR: In this paper, the influence of non-linear elastic systems on a simple geometric model for elastic deformations is discussed, and the authors propose a planar and spatial euler introduction to nonlinear analysis.
Abstract: non linear elastic deformations iwsun non linear elastic deformations erpd non linear elastic deformations hneun non-linear elastic deformations (dover civil and non-linear elastic deformations of multi-phase fluid systems non linear elastic deformations dover civil and mechanical ogden nonlinear elastic deformations pdf wordpress non-linear, elastic researchgate chapter 6 non linear material models international journal of nonlinear mechanics nonlinear elastic deformations ogden pdfslibforme international journal of non-linear mechanics 1 rubber elasticity: basic concepts and behavior non linear elastic deformations dover civil and mechanical on a non-linear wave equation in elasticity non linear elastic deformations (pdf) by r. w. ogden (ebook) exact formulations of non-linear planar and spatial euler introduction to nonlinear analysis mit opencourseware manual for the calculation of elastic-plastic materials non linear elastic axisymmetric deformation of membranes types of analysis: linear static, linear dynamic and non fracture mechanics, damage and fatigue non linear fracture chapter 2 linear elasticity freie universität the influence of non-linear elastic systems on the a simple geometric model for elastic deformations

3,871 citations

Book
01 Jan 1969
TL;DR: In this article, the authors propose a linearized theory of elasticity for tensors, which they call Linearized Theory of Elasticity (LTHE), which is based on tensors and elasticity.
Abstract: 1. Vectors and Tensors. 2. Strain and Deformation. 3. General Principles. 4. Constitutive Equations. 5. Fluid Mechanics. 6. Linearized Theory of Elasticity. Appendix I: Tensors. Appendix II: Orthogonal Curvilinear.

3,658 citations

Journal ArticleDOI
TL;DR: It is concluded that axonal damage produced by coronal head acceleration is a major cause of prolonged traumatic coma and its sequelae and is identical to that seen in severe head injury in humans.
Abstract: Traumatic coma was produced in 45 monkeys by accelerating the head without impact in one of three directions. The duration of coma, degree of neurological impairment, and amount of diffuse axonal injury (DAI) in the brain were directly related to the amount of coronal head motion used. Coma of less than 15 minutes (concussion) occurred in 11 of 13 animals subjected to sagittal head motion, in 2 of 6 animals with oblique head motion, and in 2 of 26 animals with full lateral head motion. All 15 concussioned animals had good recovery, and none had DAI. Conversely, coma lasting more than 6 hours occurred in one of the sagittal or oblique injury groups but was present in 20 of the laterally injured animals, all of which were severely disabled afterward. All laterally injured animals had a degree of DAI similar to that found in severe human head injury. Coma lasting 16 minutes to 6 hours occurred in 2 of 13 of the sagittal group, 4 of 6 in the oblique group, and 4 of 26 in the lateral group, these animals had less neurological disability and less DAI than when coma lasted longer than 6 hours. These experimental findings duplicate the spectrum of traumatic coma seen in human beings and include axonal damage identical to that seen in sever head injury in humans. Since the amount of DAI was directly proportional to the severity of injury (duration of coma and quality of outcome), we conclude that axonal damage produced by coronal head acceleration is a major cause of prolonged traumatic coma and its sequelae.

1,426 citations