title: Diffuse optical tomographic imaging of biological media by time-dependent parabolic SP(N) equations: a two-dimensional study.
abstract: We investigate the problem of retrieving the optical properties (absorption and scattering) of biological tissue from a set of optical measurements. A diffuse optical tomography (DOT) algorithm that incorporates constrained optimization methods is implemented. To improve image quality, the DOT algorithm exploits full time-domain data. The time-dependent parabolic simplified spherical harmonics equations (TD-pSPN) are used as the forward model. Time-dependent adjoint variables are resorted to in the calculation of the gradient of the objective function. Several numerical experiments for small geometric media with embedded inclusions that mimic small animal imaging are performed. In the experiments, optical coefficient values are varied in the range of realistic values for the near-infrared spectrum, including high absorption values. Single and multiparameter reconstructions are performed with the diffusion equation and higher orders of the TD-pSPN equations. The results suggest the DOT algorithm based on the TD-pSPN model outperforms the DE, and accurately reconstructs optical parameter distributions of biological media both spatially and quantitatively.
authors.affiliation: Université de Sherbrooke, Laboratoire TomOptUS, Département de Génie Electrique et de Génie Informatique, Faculté de génie, 2500 Boulevard Université, Sherbrooke, Québec, J1K 2R1, Canada.
authors.forename: Jorge
authors.initials: J
authors.lastname: Bouza Domínguez
authors.forename: Yves
authors.initials: Y
authors.lastname: Bérubé-Lauzière
mesh_terms: D000465:Algorithms; D000818:Animals; D003198:Computer Simulation; D004058:Diffusion; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008954:Models, Biological; D009391:Nephelometry and Turbidimetry / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D041622:Tomography, Optical / Q000379:methods*