Four-dimensional (4D) computed tomography (CT) is simulated by first generating a surface mesh from a single thoracic CT scan. Tetrahedralization is applied to the surface mesh to obtain a first volume mesh. Finite element analysis, using boundary constraints and load definitions, is applied to the first volume mesh to obtain a lung deformation according to an Ogden model. Constrained tetrahedralization, using control points, is applied to the lung deformation to obtain a second volume mesh, which is then deformed using mass-spring-damper simulation to produces the 4DCT.
