Image-Based Computational Modeling of the Human Circulatory and Pulmonary Systems - Methods and Applications

Foreword

Preface

Contents

Contributors

Part I Cardiac and Pulmonary Imaging, Image Processing, and Three-Dimensional Reconstruction in Cardiovascular and Pulmonary Systems

1 Image Acquisition for Cardiovascular and Pulmonary Applications

1.1 Introduction to Imaging

1.1.1 Invasive Techniques

1.1.2 Role of Noninvasive Imaging

1.2 Ultrasound/Echocardiography

1.2.1 Principles of Ultrasound

1.2.1.1 M-Mode

1.2.1.2 2D Ultrasound

1.2.2 Echocardiography

1.2.2.1 Morphologic Imaging

1.2.2.2 Function

1.2.2.3 Flow (Doppler)

1.2.2.4 TTE Versus TEE

1.2.3 Vascular/Peripheral

1.3 Computed Tomography (CT)

1.3.1 Principles of CT

1.3.1.1 Basic CT

1.3.1.2 Multidetector CT

1.3.2 Cardiac CT

1.3.2.1 Coronary Arteries

1.3.2.2 Aorta

1.3.2.3 Cardiac Function

1.3.3 Pulmonary CT

1.3.3.1 Parenchyma

1.3.3.2 Pulmonary Angiography

1.4 Magnetic Resonance Imaging (MRI)

1.4.1 Principles of MRI

1.4.1.1 Signal Generation

1.4.1.2 General Techniques and Contrast Mechanisms

1.4.1.3 Morphology

1.4.1.4 Function

1.4.1.5 Perfusion/Ischemia

1.4.2 MR Angiography

1.4.3 Pulmonary MRI: Emerging Techniques

1.5 Other Techniques

1.5.1 SPECT

1.5.2 PET

1.6 Summary

References

2 Three-dimensional and Four-dimensional Cardiopulmonary Image Analysis

2.1 Introduction

2.2 Segmentation and Modeling Methodology

2.2.1 Active Shape and Appearance Models

2.2.1.1 Building a 3D Statistical Shape Model

2.2.1.2 Extension to Higher Dimensions

2.2.1.3 Combining Shape and Appearance

2.2.1.4 Robust ASM and AAM Implementations

2.2.2 Region Growing and Fuzzy Connectivity Segmentation

2.2.2.1 Region Growing

2.2.2.2 Fuzzy Connectivity-Based Segmentation

2.2.3 Graph-Based Segmentation

2.2.3.1 Approaches Based on Rectangular Graph Structures

2.2.3.2 Minimum-Cut Approaches

2.2.3.3 Cost Functions

2.3 Cardiac Applications

2.3.1 Modeling and Quantitative Analysis of the Ventricles

2.3.1.1 Manual Ventricle Segmentation

2.3.1.2 3D Shape Generation

2.3.2 Tetralogy of Fallot Classification

2.3.2.1 Study Population and Experimental Methods

2.3.2.2 Novel Ventricular Function Indices

2.4 Vascular Applications

2.4.1 Connective Tissue Disorder in the Aorta

2.4.1.1 4D Segmentation of Aortic MR Image Data

2.4.1.2 Disease Detection

2.4.1.3 Accuracy of Segmentation and Classification

2.4.2 Aortic Thrombus and Aneurysm Analysis

2.4.2.1 Initial Luminal Surface Segmentation

2.4.2.2 Graph Search and Cost Function Design

2.4.2.3 Data and Results

2.4.3 Plaque Distribution in Coronary Arteries

2.4.3.1 Segmentation and 3D Fusion

2.4.3.2 Hemodynamic and Morphologic Analysis

2.4.3.3 Studies and Results

2.5 Pulmonary Applications

2.5.1 Segmentation and Quantitative Analysis of Airway Trees

2.5.1.1 Airway Tree Segmentation

2.5.1.2 Quantitative Analysis of Airway Tree Morphology

2.5.2 Quantitative Analysis of Pulmonary Vascular Trees

2.5.3 Segmentation of Lung Lobes

2.6 Discussions and Conclusions

References

Part II Computational Techniques for Fluid and Soft Tissue Mechanics, FluidStructure Interaction, and Development of Multi-scale Simulations

3 Computational Techniques for Biological Fluids: From Blood Vessel Scale to Blood Cells

3.1 Introduction

3.2 Computational Methods for Macro-scale Hemodynamics

3.2.1 Governing Equations

3.2.1.1 The Fluid Flow Equations

3.2.1.2 The Structural Equations

3.2.1.3 Boundary Conditions at the Fluid--Structure Interface

3.2.2 Numerical Methods for Flows with Moving Boundaries

3.2.2.1 Boundary-Conforming Methods

3.2.2.2 Non-boundary-Conforming Methods

3.2.2.3 Hybrid Methods: Body-Fitted/Immersed Boundary Methods

3.2.3 Fluid--Structure Interaction Algorithms

3.2.3.1 Loose and Strong Coupling Strategies

3.2.3.2 Stability and Robustness Issues

3.2.4 Efficient Solvers for Physiologic Pulsatile Simulations

3.2.5 High-Resolution Simulations of Cardiovascular Flow

3.2.5.1 Fluid--Structure Interaction Simulations of Mechanical Bileaflet Heart Valves

3.2.5.2 Numerical Simulations of Trileaflet Heart Valve Hemodynamics

3.3 Computational Methods for Blood Cell Scale Simulations

3.3.1 Background

3.3.2 Review of Numerical Methods for Blood Cell-Resolving Simulations

3.3.2.1 Boundary-Integral Methods for Cell-Level Simulation

3.3.2.2 Immersed Boundary Method

3.3.2.3 Particle Methods

3.3.2.4 Lattice Boltzmann

3.3.3 Lattice-Boltzmann Methodology

3.3.3.1 Lattice-Boltzmann BGK (LBGK) Model for Fluid Flow

3.3.3.2 Transient Finite-Element FSI Model

3.3.4 Membrane Models

3.3.4.1 Comparison of Red Blood Cell Models

3.3.5 Rheology, Stress, and Microstructure of Blood

3.3.5.1 Bulk Rheology

3.3.5.2 Shear-Thinning Behavior

3.3.5.3 Microstructure

3.3.5.4 Local Stress Environment in Blood

3.4 Future Directions

References

4 Formulation and Computational Implementation of Constitutive Models for Cardiovascular Soft Tissue Simulations

4.1 Introduction

4.2 Constitutive Models for Cardiovascular Soft Tissues

4.2.1 Condition Number of D

4.3 Structural Constitutive Models

4.4 Finite-Element Implementation

4.4.1 Fung Model Implementation Example

4.4.2 Biaxial Testing Simulations

4.4.3 Prosthetic Valve Simulations

4.4.4 Engineered Heart Valve Leaflet Tissue Simulations

4.5 Finite-Element Models of Heart Valve Leaflets

4.5.1 Degenerate Solid Shell

4.5.2 Element Pathology

4.5.3 Stress-Resultant Shell

4.5.4 Continuum Shell

4.6 Summary

4.7 Appendix: Shell Kinematics

References

5 Algorithms for Fluid Structure Interaction

5.1 Introduction

5.1.1 Key Aspects of Fluid--Structure Interaction Problems

5.2 Governing Equations and Important Parameters

5.3 Spatial Discretization to Couple Fluid and Solid Dynamics

5.4 ALE-Type Methods

5.5 Immersed Boundary Method

5.6 Immersed Interface Method

5.7 Sharp Interface Method

5.8 Finite Element Methods

5.9 Fictitious Domain Method

5.10 Immersed Finite Element Methods

5.11 Issues Related to the Temporal Update of the Coupled FluidSolid System

5.12 Numerical Stiffness

5.13 Material Density and Slenderness

5.14 Rapidity of Motion and Deformation

5.15 Techniques for Coupling of the Temporal Update of the Fluid and Solid Subsystems

5.16 Weak and Strong Coupling Algorithms

5.17 Three Different Approaches to FSI Modeling in Biomedical Applications

5.17.1 FSI Approach 1

5.17.1.1 Results

5.17.2 FSI Approach 2

5.17.2.1 Results

5.17.3 FSI Approach 3

5.18 Modeling of Mechanical Heart Valves

5.19 Leaflet Rebound

5.19.1 Results

5.20 Effect of Flow During Closure and Rebound Phases

5.21 Modeling of Tissue Heart Valves

5.21.1 Challenges in Modeling Tissue Heart Valves

5.21.1.1 Results of Simulations

5.22 Concluding Remarks

References

6 Mesoscale Analysis of Blood Flow

6.1 Introduction

6.2 Scaling Estimates

6.3 Modeling Adhesion Force Between Blood Cells

6.4 Microscale Modeling: Deformable Blood Cells

6.5 Mesoscale Modeling Using the Discrete Element Method

6.6 Mesoscale Modeling Using Dissipative Particle Dynamics

6.7 Bridging the Scales

References

Part III Applications of Computational Simulations in the Cardiovascular and Pulmonary Systems

7 Arterial Circulation and Disease Processes

7.1 Introduction

7.2 Artery Wall Structure

7.3 Endothelium

7.4 Mechanical Forces on the Arterial Wall

7.5 Wall Shear Stress

7.6 Mechanisms of Disease Formation

7.7 Flow in Small Vessels Hemodynamic Modelling of Coronary Flows

7.8 The Influence of Wall Motion

7.9 Boundary Conditions for Coronary Flows

7.10 Velocity

7.11 Outlet Boundary Conditions for Coronary Flows

7.12 Numerical Model Development

7.13 Coronary Flow Analysis

7.14 Steady Flow in the Right Coronary Artery

7.15 Pulsatile Flow in the Right Coronary Artery

7.16 Steady Flow in the Left Coronary Artery

7.17 Pulsatile Flow in the Left Coronary Artery

7.18 Discussion

7.19 Flow in Large Vessels Hemodynamic Modeling of Aortic Flows

7.20 Boundary Conditions

7.21 Steady-Flow Boundary Conditions

7.22 Steady Flow Realistic Model

7.23 Influence of Steady Input Boundary Conditions

7.24 Pulsatile Flow in a Bifurcation

7.25 Geometrical Effects

7.26 Geometrical Differences Associated with the Realistic and Idealized AAA Models

7.27 Treatment of Arterial Disease

7.27.1 Vascular Aneurysm Grafting

7.27.2 Vascular Bypass Grafting

7.28 Future Trends in Vascular and Cardiovascular Disease Modeling

References

8 Biomechanical Modeling of Aneurysms

8.1 Introduction

8.1.1 Incidence and Epidemiology

8.1.2 Role for Biomechanical Modeling and Simulation

8.2 Geometric Modeling of Aneurysms

8.2.1 Abdominal Aortic Aneurysms

8.2.2 Cerebral Aneurysms

8.2.3 Summary

8.3 Material Modeling of Aneurysms

8.3.1 Abdominal Aortic Aneurysms

8.3.2 Cerebral Aneurysms

8.4 Computational Simulations of Intra-aneurysmal Hemodynamics

8.4.1 Abdominal Aortic Aneurysm

8.4.2 Cerebral Aneurysms

8.4.3 Challenges in Aneurismal Hemodynamic Simulations

8.5 Computational Estimations of Aneurysmal Wall Stress and Strain

8.5.1 Abdominal Aortic Aneurysm

8.5.2 Cerebral Aneurysms

8.6 FluidStructure Interaction Studies

8.7 Framework for Biomechanical Modeling of Growth and Remodeling

8.8 Future Directions

References

9 Advances in Computational Simulations for Interventional Treatments and Surgical Planning

9.1 Introduction

9.2 Analysis for Endovascular Treatment and Device Design

9.2.1 Introduction

9.2.2 Identification of Vulnerable Plaque

9.2.3 Endovascular Balloon Angioplasty

9.2.4 Endovascular Stents

9.3 Patient-Specific Surgical Planning

9.3.1 Single-Ventricle Heart Defects: Review of the Clinical Problem

9.3.2 Comparing Global Outcome and Cardiovascular Function

9.3.3 Comparing Performances of Different Design Variations

9.3.3.1 Patient Data Acquisition

9.3.3.2 Anatomy Reconstruction and Surrounding Organs Representation

9.3.3.3 Modeling the Intervention

9.3.3.4 Fast Performance Estimation and Optimization Using 1D FEA Modeling

9.3.3.5 Full Postoperative Hemodynamics Characterization and Optimization Using 3D CFD

9.3.3.6 Automated Optimization Methods Using 3D CFD

9.4 Including Surrounding Organs

9.4.1 Geometric Constraints of the Modified Configuration

9.4.2 Adapting the Boundary Conditions to the Modified Configuration

9.4.2.1 Inlet and Outlet Boundary Conditions

9.4.2.2 Material Properties

9.5 Future Direction for Biomedical Simulations

References

10 Computational Analyses of Airway Flow and Lung Tissue Dynamics

10.1 Introduction

10.2 Basic Anatomy and Physiology

10.3 Respiratory Mechanics

10.4 Mechanical Input Impedance

10.4.1 Inverse Modeling of Respiratory Mechanics

10.5 Forward Morphometric Models of the Respiratory System

10.5.1 Computational Modeling Example: Airway Thermodynamics in Symmetric and Anatomical Models

10.6 Application of Morphometric Models to Computational Studies of Lung Mechanics

10.7 Imaging Methodology

10.8 Image-Based Computational Models

10.8.1 Insights into Bronchoconstriction: Airways and Interdependence

10.8.2 Regional Tissue Mechanics

10.9 Conclusions

References

11 Native Human and Bioprosthetic Heart Valve Dynamics

11.1 Human Heart Valves

11.2 Aortic Valve

11.3 Mitral Valve

11.4 Diseases of the Heart Valves

11.5 Biological Valve Prostheses

11.6 Experimental Studies on Valve Dynamics

11.7 Three-Dimensional Geometrical Reconstruction of the Aortic and Mitral Valves

11.7.1 3D Echocardiography

11.7.2 3D Computed Tomography

11.7.3 3D Magnetic Resonance Imaging

11.8 Computational Simulations of the Native Valves

11.8.1 Aortic Valve

11.8.2 Mitral Valve

11.9 Biological Valve Prostheses

11.9.1 Quasi-Static and Dynamic FE Analyses

11.9.2 Fluid--Structure Interaction Analysis

11.10 Need for Multiscale Simulations

11.11 Summary

References

12 Mechanical Valve Fluid Dynamics and Thrombus Initiation

12.1 Background

12.1.1 Heart Valve Disease

12.1.2 Artificial Heart Valves

12.1.2.1 Mechanical Heart Valves

12.1.2.2 Bioprosthetic Heart Valves

12.1.3 Design and Performance Issues

12.1.4 Computational Fluid Dynamics

12.1.5 Experimental Fluid Dynamics

12.2 FluidStructure Interaction

12.2.1 The Need for Fluid--Structure Interaction

12.2.1.1 Monolithic vs. Partitioned Methods and Loose vs. Strong Coupling

12.2.1.2 Moving Grid Methods

12.2.1.3 Fixed Grid Methods

12.3 Modeling Damage to Blood Cells

12.3.1 Thrombus Formation and Hemolysis

12.3.2 Modeling Blood Damage

12.3.3 Implementation of Blood Damage Models in CFD

12.4 Concluding Remarks

References

Subject Index