Reliable recovery of the optical properties of multi-layer turbid media by iteratively using a layered diffusion model at multiple source-detector separations

Abstract

Accurately determining the optical properties of multi-layer turbid media using a layered diffusion model is often a difficult task and could be an ill-posed problem. In this study, an iterative algorithm was proposed for solving such problems. This algorithm employed a layered diffusion model to calculate the optical properties of a layered sample at several source-detector separations (SDSs). The optical properties determined at various SDSs were mutually referenced to complete one round of iteration and the optical properties were gradually revised in further iterations until a set of stable optical properties was obtained. We evaluated the performance of the proposed method using frequency domain Monte Carlo simulations and found that the method could robustly recover the layered sample properties with various layer thickness and optical property settings. It is expected that this algorithm can work with photon transport models in frequency and time domain for various applications, such as determination of subcutaneous fat or muscle optical properties and monitoring the hemodynamics of muscle.

Pressure Modulation Algorithm to Separate Cerebral Hemodynamic Signals from Extracerebral Artifacts

“…Thus, it is preferable not to filter systemic components from the measured signals. In a different vein, computationally intense models have been explored to handle extracerebral heterogeneities directly, including layered models, [41][42][43][44][45][46][47][48][49] Monte Carlo techniques in realistic geometries of the head, [50][51][52][53] and imaging. 27,[54][55][56] The complexity of these models, however, can make them impractical to implement for real-time monitoring.…”

Pressure modulation algorithm to separate cerebral hemodynamic signals from extracerebral artifacts

“…Thus, it is preferable not to filter systemic components from the measured signals. In a different vein, computationally intense models have been explored to handle extracerebral heterogeneities directly, including layered models, [41][42][43][44][45][46][47][48][49] Monte Carlo techniques in realistic geometries of the head, [50][51][52][53] and imaging. 27,[54][55][56] The complexity of these models, however, can make them impractical to implement for real-time monitoring.…”

Noninvasive transcutaneous bilirubin assessment of neonates with hyperbilirubinemia using a photon diffusion theory-based method

“…The photon propagation model for the diffusing probe has been described in detail in previous publications [24][25][26][27]. Here, we recapitulated the key steps of model derivation.…”