We developed an adaptive boundary and finite element mesher, namely, a Level Set Bounded Interior and Exterior(LBIE)-mesher that produces high quality meshes. This mesher has also been used for studying diffusion in biomolecular systems using continuum mechanics equations. Specifically, finite element methods have been developed to solve the steady-state Smoluchowski equation to calculate ligand binding rate constants for large biomolcules. The approach taken by our LBIE-mesher tetrahedralizes or hexahedralizes the interval volume between the biomolecular surface and an outer boundary sphere which is usually 20-40 times that of the biomolecule.
We converted a simple triangular surface mesh (describing the heart) into volumetric data using the signed distance method. We then extracted tetrahedral meshes from the volumetric data.
These images are of the heart model with valve gaps. The meshes are adaptive tetrahedral meshes, with the valve areas set to the finest level of the mesh.
A cross-section of the adaptive tetrahedral mesh of the heart
The view from outside
The wireframe shows the inner structure of the heart
The result of boundary detection in wireframe, each of the twenty-two components of the heart model is represented by a different color
A cross section of the adaptive tetrahedral mesh, it is obvious that the valves have the finest mesh, thin structures are identified by the feature sensitive error function, and adaptive meshes are generated to preserve correct topology.
the aortic valve
the mitral valve
the pulmonary valve
the tricuspid valve
a cross section of the mitral valve before material layer detection
a cross section of the mitral valve after material layer detection
Credits
The original surface mesh of the heart model was acquired from New York University.
Information about this virtual heart model can be found
here.
