NA-MIC
National Alliance for Medical Image Computing
http://na-mic.org
Toward Automating Patient-Specific
Finite Element Model Development
Nicole M. Grosland, Vincent A. Magnotta,
Kiran H. Shivanna, Steve Pieper, Curt Lisle
Patient Specific Models
• In order to bring FE to the “bedside” for
guiding surgical procedures the technique
must be unencumbered from the image
segmentation and mesh generation
process
• Overcome the limitations associated with
individualized, or patient-specific models
National Alliance for Medical Image Computing
http://na-mic.org
Progress
• June – Flood closes campus for two weeks with
alternate working arrangements for an additional
month
National Alliance for Medical Image Computing
http://na-mic.org
Progress
• August – Completed meshing workflow and
released a stand-alone application, IA-FEMesh,
using the NA-MIC toolkit
• October – Visit by Curt Lisle to work on
integration of meshing workflow into Slicer3
• December – Meshing workflow integrated into
Slicer3 trunk
• January – Meshing tutorial presented at AHM
National Alliance for Medical Image Computing
http://na-mic.org
Meshing Module
IA-FEMesh Standalone application
Slicer3 Integration
National Alliance for Medical Image Computing
http://na-mic.org
Meshing Workflow
National Alliance for Medical Image Computing
http://na-mic.org
Building Block Editing
National Alliance for Medical Image Computing
http://na-mic.org
Mirror and Merging Blocks
National Alliance for Medical Image Computing
http://na-mic.org
Mesh Quality Evaluation
Summary Report
National Alliance for Medical Image Computing
http://na-mic.org
Node/Element Set Selection
National Alliance for Medical Image Computing
http://na-mic.org
Load / BC Verification
National Alliance for Medical Image Computing
http://na-mic.org
Additional Features
• Control over mesh density
• Mesh improvement
• Assignment of loads and boundary
conditions
• Assignment of material properties
– Constant
– Image intensity
• Ability to create a uniform cartilage layer
• Export to ABAQUS
National Alliance for Medical Image Computing
http://na-mic.org
Mesh Comparisons
National Alliance for Medical Image Computing
http://na-mic.org
Accuracy & Validity Studies
National Alliance for Medical Image Computing
http://na-mic.org
Phalanx Bones and PIP Implant
National Alliance for Medical Image Computing
http://na-mic.org
Carpal Bones and UTW2
National Alliance for Medical Image Computing
http://na-mic.org
Mechanical Joint
National Alliance for Medical Image Computing
http://na-mic.org
Brain Mesh
National Alliance for Medical Image Computing
http://na-mic.org
Future Work
• Mapped mesh extension
– Mapping of building block structure to complicated geometries
– Development of Slicer3 execution model
– Evaluate for speed improvements
• Refinement of Slicer3 Integration
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–
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Allow sharing of data between Slicer3 and meshing module
Improved integration of custom actors
Complete scene snapshot / restore
Module specific application settings
Add GUI tests using Squish
• Further refinement of Slicer3 EM Segmentation tools for
use with CT data
• Test meshing module in the course “Applied Biomedical FE
Modeling” offered at the University of Iowa
National Alliance for Medical Image Computing
http://na-mic.org
Publications
• DeVries NA, Gassman EE, Kallemeyn NA, Shivanna KH, Magnotta VA, Grosland NM.,
Validation of phalanx bone three-dimensional surface segmentation from computed
tomography images using laser scanning, Skeletal Radiol. 2008 Jan;37(1):35-42.
• Gassman EE, Powell SM, Kallemeyn NA, Devries NA, Shivanna KH, Magnotta VA,
Ramme AJ, Adams BD, Grosland NM., Automated bony region identification using
artificial neural networks: reliability and validation measurements. Skeletal Radiol.
2008 Apr;37(4):313-9.
• Grosland NM, Bafna R, Magnotta VA., Automated hexahedral meshing of anatomic
structures using deformable registration. Comput Methods Biomech Biomed Engin.
2008 Aug 7:1. [Epub ahead of print]
• Ramme AJ, Devries N, Kallemyn NA, Magnotta VA, Grosland NM., Semi-automated
Phalanx Bone Segmentation Using the Expectation Maximization Algorithm. J Digit
Imaging. 2008 Sep 3. [Epub ahead of print]
• Magnotta V, Li W, Grosland N. Comparison of Displacement-Based and Force-Based
Mapped Meshing. Workshop on Computational Biomechanics for Medicine at MICCAI
2008. Insight Journal, http://hdl.handle.net/1926/1490 , 2008.
• Grosland NM, Shivanna KH, Magnotta VA, Kallemeyn NA, DeVries NA, Tadepalli SC,
Lisle C., IA-FEMesh: An open-source, interactive, multiblock approach to
musculoskeletal finite element model development, Comput Methods Programs
Biomed (in press).
National Alliance for Medical Image Computing
http://na-mic.org
Acknowledgements
• Grant funding NIH/NIBIB
– R21 (EB001501)
– R01 (EB005973)
• Nicole Kallemeyn, Nicole DeVries, Esther Gassman,
Ritesh Bafna, Srinivas Tadepalli, Austin Ramme, Wen Li,
Dr. Brian Adams
National Alliance for Medical Image Computing
http://na-mic.org
National Alliance for Medical Image Computing
http://na-mic.org