The event database contains all event-related information for the World of Photonics Congress.
Poster Hall B0 European Conferences on Biomedical Optics (ECBO) > Diffuse Optical Spectroscopy and Imaging > Lunch Break and Poster Session - Monday
12:45-14:15 h | Hall B0 Hall B0, ICM
Subjects: Biophotonics and Medical Engineering
In diffuse optical tomography (DOT), the diffusion equation (DE) is frequently used to model the light propagation in the medium. A general approach to solve the DE analytically is to apply the Green function but the solution only exists for homogeneous objects. For more complex DOT geometries, the finite element method (FEM) is normally employed to discretize the DE. However, FEM is limited in acquiring higher order accuracy when higher order basis (shape) functions are involved. Currently the differential operators in the DE are based on the classical local vector calculus. In this paper, by using the concepts of differential operators under the nonlocal vector calculus, we propose a nonlocal diffusion equation (NDE) as a new forward model to accurately describe light propagation in a turbid medium. A graph-based numerical method (GNM) is developed for the proposed NDE. We evaluate the proposed forward model on a semi-infinite homogeneous slab where the analytical solution exists. We perform a systematic comparison between the forward model based on GNM and the analytical solution. The comparison considers: i) the photon boundary flux at each detector; ii) the photon fluence rate at each vertex. Our experiments show that the results of the NDE (discretized by GNM) is quantitatively comparable to the analytical solution. The proposed forward model has an identical implementation for geometries in two and three dimensions due to the nature of the graph representation.