Light transport in biological tissue using three-dimensional frequency-domain simplified spherical harmonics equations

Chu, Michael; Vishwanath, Karthik; Klose, Alexander D.; Dehghani, Hamid

doi:10.1088/0031-9155/54/8/016

Cited by 63 publications

(50 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…where c m denote the speed of light in the medium,ŝ andŝ denote the direction of the outgoing and incoming photons, respectively, and p(ŝ,ŝ |r) denotes the scattering phase function, which in biological tissue is typically given by the Henyey-Greenstein function [35,36]: where the anisotropy factor α characterizes the angular distribution of scattering in the tissue. The attenuation operator X X X is the standard attenuated X-ray transform, and its effect on the distribution function is given by [25] […”

Section: Evaluating the Gradient Of The Mean Image Datamentioning

confidence: 99%

An ideal-observer framework to investigate signal detectability in diffuse optical imaging

Jha¹,

Clarkson²,

Kupinski³

2013

Biomed. Opt. Express

View full text Add to dashboard Cite

With the emergence of diffuse optical tomography (DOT) as a non-invasive imaging modality, there is a requirement to evaluate the performance of the developed DOT systems on clinically relevant tasks. One such important task is the detection of high-absorption signals in the tissue. To investigate signal detectability in DOT systems for system optimization, an appropriate approach is to use the Bayesian ideal observer, but this observer is computationally very intensive. It has been shown that the Fisher information can be used as a surrogate figure of merit (SFoM) that approximates the ideal observer performance. In this paper, we present a theoretical framework to use the Fisher information for investigating signal detectability in DOT systems. The usage of Fisher information requires evaluating the gradient of the photon distribution function with respect to the absorption coefficients. We derive the expressions to compute the gradient of the photon distribution function with respect to the scattering and absorption coefficients. We find that computing these gradients simply requires executing the radiative transport equation with a different source term. We then demonstrate the application of the SFoM to investigate signal detectability in DOT by performing various simulation studies, which help to validate the proposed framework and also present some insights on signal detectability in DOT. In vivo hemoglobin and water concentrations, oxygen saturation, and scattering estimates from near-infrared breast tomography using spectral reconstruction," Acad. Radiol. 13, 195-202 (2006).

show abstract

Section: Evaluating the Gradient Of The Mean Image Datamentioning

confidence: 99%

An ideal-observer framework to investigate signal detectability in diffuse optical imaging

Jha¹,

Clarkson²,

Kupinski³

2013

Biomed. Opt. Express

View full text Add to dashboard Cite

show abstract

“…To simulate the photon propagation in tissues in small animals, the high-order simplified harmonics spherical ( N SP ) is used to provide more accurate simulations compared to classic diffusion approximation (DA) [22][23][24]. We developed a fully parallel linear reconstruction algorithm for fluorescence gene reporter tomography [25].…”

Section: Fluorescence Gene Reporter Tomography (Fgrt) Algorithmmentioning

confidence: 99%

“…We developed a fully parallel linear reconstruction algorithm for fluorescence gene reporter tomography [25]. Specifically, the 3 SP approximation in the CW mode is as follows [22][23][24]: …”

Section: Fluorescence Gene Reporter Tomography (Fgrt) Algorithmmentioning

confidence: 99%

Far-red fluorescence gene reporter tomography for determination of placement and viability of cell-based gene therapies

Lu¹,

Darne²,

Tan³

et al. 2013

Opt. Express

View full text Add to dashboard Cite

Non-invasive injectable cellular therapeutic strategies based on sustained delivery of physiological levels of BMP-2 for spinal fusion are emerging as promising alternatives, which could provide sufficient fusion without the associated surgical risks. However, these injectable therapies are dependent on bone formation occurring only at the specific target region. In this study, we developed and deployed fluorescence gene reporter tomography (FGRT) to provide information on in vivo cell localization and viability. This information is sought to confirm the ideal placement of the materials with respect to the area where early bone reaction is required, ultimately providing three dimensional data about the future fusion. However, because almost all conventional fluorescence gene reporters require visible excitation wavelengths, current in vivo imaging of fluorescent proteins is limited by high tissue absorption and confounding autofluorescence. We previously administered fibroblasts engineered to produce BMP-2, but is difficult to determine 3-D information of placement prior to bone formation. Herein we used the far-red fluorescence gene reporter, IFP1.4 to report the position and viability of fibroblasts and developed 3-D tomography to provide placement information. A custom small animal, far-red fluorescence tomography system integrated into a commercial CT scanner was used to assess IFP1.4 fluorescence and to demark 3-D placement of encapsulated fibroblasts with respect to the vertebrae and early bone formation as assessed from CT. The results from three experiments showed that the placement of the materials within the spine could be detected. This work shows that in vivo fluorescence gene reporter tomography of cell-based gene therapy is feasible and could help guide cell-based therapies in preclinical models.

show abstract

“…For this reason, various approximations of RTE have been proposed in the literature, e.g., the delta-Eddington approximation [13], the Fokker-Planck approximation [20,21], the Boltzmann-Fokker-Planck approximation [22,5], the generalized Fokker-Planck approximation [16], the Fokker-Planck-Eddington approximation and the generalized Fokker-Planck-Eddington approximation [10]. For RTE with high absorption and small geometries, the simplified spherical harmonics (S P N ) method ( [14]) is shown to produce good approximate solutions ( [9]). Well-posedness of the (S P N ) method is shown in [25].…”

Section: Introductionmentioning

confidence: 99%

On a family of differential approximations of the radiative transfer equation

2011

View full text Add to dashboard Cite

The radiative transfer equation (RTE) arises in a variety of applications and is challenging to solve numerically due to its integro-differential form and high dimension. For highly forward-peaked media, it is even more difficult to solve RTE since accurate numerical solutions require a high resolution of the direction variable. For this reason, various approximations of RTE have been proposed in the literature. In this paper, we study a family of differential approximations of the RTE in three spatial variables. We explain the idea of constructing the differential approximations, and comment on the usefulness of the approximations.

show abstract

Light transport in biological tissue using three-dimensional frequency-domain simplified spherical harmonics equations

Cited by 63 publications

References 50 publications

An ideal-observer framework to investigate signal detectability in diffuse optical imaging

An ideal-observer framework to investigate signal detectability in diffuse optical imaging

Far-red fluorescence gene reporter tomography for determination of placement and viability of cell-based gene therapies

On a family of differential approximations of the radiative transfer equation

Contact Info

Product

Resources

About