title: Extended finite element method with simplified spherical harmonics approximation for the forward model of optical molecular imaging.
abstract: An extended finite element method (XFEM) for the forward model of 3D optical molecular imaging is developed with simplified spherical harmonics approximation (SP(N)). In XFEM scheme of SP(N) equations, the signed distance function is employed to accurately represent the internal tissue boundary, and then it is used to construct the enriched basis function of the finite element scheme. Therefore, the finite element calculation can be carried out without the time-consuming internal boundary mesh generation. Moreover, the required overly fine mesh conforming to the complex tissue boundary which leads to excess time cost can be avoided. XFEM conveniences its application to tissues with complex internal structure and improves the computational efficiency. Phantom and digital mouse experiments were carried out to validate the efficiency of the proposed method. Compared with standard finite element method and classical Monte Carlo (MC) method, the validation results show the merits and potential of the XFEM for optical imaging.
authors.affiliation: Life Sciences Research Center, School of Life Sciences and Technology, Xidian University, Xi'an, Shaanxi 710071, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Huangjian
authors.initials: H
authors.lastname: Yi
authors.forename: Qitan
authors.initials: Q
authors.lastname: Zhang
authors.forename: Duofang
authors.initials: D
authors.lastname: Chen
authors.forename: Jimin
authors.initials: J
authors.lastname: Liang
mesh_terms: D000465:Algorithms; D000818:Animals; D003198:Computer Simulation; D020342:Finite Element Analysis; D007091:Image Processing, Computer-Assisted; D051379:Mice; D015233:Models, Statistical; D057054:Molecular Imaging / Q000379:methods*; D009010:Monte Carlo Method; D016011:Normal Distribution; D061848:Optical Imaging / Q000379:methods*; D055095:Optics and Photonics / Q000379:methods*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted; D012984:Software; D013499:Surface Properties