Three-dimensional diffuse optical tomography with full multi-view time-domain data

Abstract

In this work, synthetic time-domain data are generated as if it were collected with a state-of-the-art multi-view experimental optical scanner developed in our group for small animal imaging, and used in a tomographic image reconstruction algorithm. The collected data comprises full time-dependent optical signals leaving the biological medium and acquired all around the medium. The diffuse optical tomography (DOT) algorithm relies on the timedependent parabolic simplified spherical harmonics (TD-pSPN) equations as the forward model to recover the 3D absorption and diffusion coefficient maps of the medium. The inverse problem is casted and solved as an iterative constrained optimization problem where an objective function determines the accuracy of the forward model predictions at each iteration. Time-dependent adjoint variables are introduced to accelerate the calculation of the gradient of the objective function. A three-dimensional case involving an absorption heterogeneity in a homogeneous medium is presented, reproducing practical situations encountered in our lab. The results support our hypothesis that accurate quantitative 3D maps of optical properties of biological tissues can be retrieved using intrinsic measurements obtained with our experimental scanner along with our DOT algorithm.

Differential photon waves imaging

“…Matrix form is the product of forward-model problem. [91][92][93][94][95][96][97][98][99][100][101][102][103][104] The picture which the photon fluencies draw inside the tissue explains that for any kind of live tissue, forward-model problem photon weights which are generated from SD positions have uncertainties. This situation shows itself when someone tries to use photon fluencies inside the inverse problem solution algorithms.…”

“…This structure is creating the matrix form. Matrix form is the product of forward‐model problem 91‐104 . The picture which the photon fluencies draw inside the tissue explains that for any kind of live tissue, forward‐model problem photon weights which are generated from SD positions have uncertainties.…”