Investigation on the reflection at the boundaries for reconstruction laser-based imaging

Abstract

Optical tomography is acknowledged as an economic and harmless probing technique for medical applications. Recent research tends to show that the use of long term photons, which have travelled a long time in the whole sample to be probed, carry more information in the image reconstruction process. Numerical simulations based on short-pulsed laser beam interaction with non-homogeneous matter are presented. The aim is to emphasize the effect of reflective boundary conditions since reflection enforces photons to stay for a longer period of time in the phantom. It is found that the quality of reconstruction is better when the boundaries are reflecting. Crown

Fluorescence molecular imaging based on the adjoint radiative transport equation

“…were derived by Boulanger et al [69]. Here we propose to adapt these boundary conditions for the adjoint RTE in the frequency domain.…”

“…(A.7) The equations ( 17) and (A. The boundary conditions of the adjoint RTE in the time domain for semi-transparent boundaries (with diffuse reflection) were derived by Boulanger et al [69]. Here we propose to adapt these boundary conditions for the adjoint RTE in the frequency domain.…”

“…Previous analyses dealing with the adjoint for mulations of the RTE can be found in [62][63][64]. The adjoint method was applied to DOT problems based on RTE in the time domain [65][66][67][68][69] and the frequency domain [70][71][72][73][74][75]. In the reports cited, a forward model including partly reflected boundary conditions (Fresnel reflection) was considered in [71].…”

Boundary Effects on the Efficiency of Direct Infra-Red Optical Tomography

“…For inverse reconstruction problems, it is worth noting that reflective boundary conditions are a way to enforce photons to stay longer within the sample. This has the same effects as long-term filtering, as demonstrated in [35], while being applicable to steady-state [26] or frequency-domain techniques [36,37,38]. In these latter approaches, time filtering is not available.…”

New image reconstruction algorithm for fluorescence optical tomography based on the adjoint radiative transfer equation

“…Thus, it allows more accurate computing of the objective function gradient and the computational cost is much lower than for the finite differences method. The adjoint method was applied to DOT problems based on RTE in the time domain 8 and the frequency domain. 9 In the reports cited, a forward model including partly reflected boundary conditions (Fresnel reflection) was considered in.…”