A multi-laboratory comparison of photon migration instruments and their performances: the BitMap exercise

The Monte Carlo code MCML (Monte Carlo modeling of light transport in multi-layered tissue) has been the gold standard for simulations of light transport in multi-layer tissue, but it is ineffective in the presence of three-dimensional (3D) heterogeneity. New techniques have been attempted to resolve this problem, such as MCLS, which is derived from MCML, and tMCimg, which draws upon image datasets. Nevertheless, these approaches are insufficient because of their low precision or simplistic modeling. We report on the development of a novel model for photon migration in voxelized media (MCVM) with 3D heterogeneity. Voxel crossing detection and refractive-index-unmatched boundaries were considered to improve the precision and eliminate dependence on refractive-index-matched tissue. Using a semi-infinite homogeneous medium, steady-state and time-resolved simulations of MCVM agreed well with MCML, with high precision (~100%) for the total diffuse reflectance and total fractional absorption compared to those of tMCimg (< 70%). Based on a refractive-index-matched heterogeneous skin model, the results of MCVM were found to coincide with those of MCLS. Finally, MCVM was applied to a two-layered sphere with multi-inclusions, which is an example of a 3D heterogeneous media with refractive-index-unmatched boundaries. MCVM provided a reliable model for simulation of photon migration in voxelized 3D heterogeneous media, and it was developed to be a flexible and simple software tool that delivers high-precision results.

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Spectroscopy in heterogenous media and applications for bioprocess and environmental monitoring

International Journal of Photoenergy ◽

10.1155/s1110662x02000041 ◽

2002 ◽

Vol 4 (1) ◽

pp. 21-26 ◽

Cited By ~ 3

Author(s):

Frank Schael ◽

Oliver Reich ◽

Sonja Engelhard

Keyword(s):

Diffuse Reflectance ◽

Near Infrared ◽

Transport Theory ◽

Radiation Transport ◽

Diffusion Theory ◽

Nile Blue ◽

Milk Powder ◽

Photon Migration ◽

Heterogenous Media ◽

Reflectance Measurements

Diffuse reflectance measurements and photon migration studies with near infrared (NIR) diode lasers were employed to elucidate experimental methods for determining absorption and scattering coefficients and species concentrations in heterogenous media. Measurements were performed at a number of wavelengths utilizing several laser sources some of which were widely tunable. In order to establish the applicability of simple photon migration models derived from radiation transport theory and to check the experimental boundary conditions of our measurements, simple light scattering solutions (such as suspensions of titanium dioxide, latex particles, and solutions of milk powder) containing dyes (such as nile blue, isosulfan blue) were investigated. The results obtained from diffuse-reflectance studies at different sourcedetector distances were in accordance with predictions from simple photon diffusion theory. Applications of reflectance measurements for monitoring of cell growth during fermentation processes and forin-situinvestigations of soils are presented.

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Frequency domain photon migration measurements of dense monodisperse charged lattices and analysis using solutions of Ornstein Zernike equations

Journal of Colloid and Interface Science ◽

10.1016/j.jcis.2012.07.044 ◽

2012 ◽

Vol 386 (1) ◽

pp. 114-120

Author(s):

Sarabjyot S. Dali ◽

Eva M. Sevick-Muraca

Keyword(s):

Frequency Domain ◽

Photon Migration

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Research on the Near-Infrared (NIR) Photon Migration in the Knee

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.760-762.388 ◽

2013 ◽

Vol 760-762 ◽

pp. 388-391

Author(s):

Yan Ping Chen ◽

Xiong Ma ◽

Chun Bin Li ◽

Song Qing Chen

Keyword(s):

Monte Carlo ◽

Muscle Tissue ◽

Layered Structure ◽

Near Infrared ◽

Propagation Model ◽

Osteoarthritis Of The Knee ◽

Photon Migration ◽

Photon Propagation ◽

Non Invasive ◽

Distribution Rule

To study the phenomena of photon migration in the knee joint is very important in the field of non-invasive near-infrared optical early diagnosis of osteoarthritis of the knee (KOA). In this paper, a photon propagation model of the knee layered structure based on Monte Carlo method is proposed. The migration trace and distribution rule of the photons in knee layered structure are simulated by the Monte Carlo modeling. The proportion of photons which collide with bone tissue then migrate out of the muscle tissue and photons directly migrate out of muscle tissue is calculated and analyzed. The conclusion is that the MC method provided in this study is useful to analyze the photon migration in knee layered structure and to place the detector in a suitable position.

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