# Inverse problem in refractive index based optical tomography

@article{Khan2005InversePI, title={Inverse problem in refractive index based optical tomography}, author={Taufiquar R. Khan and Alan Thomas}, journal={Inverse Problems}, year={2005}, volume={22}, pages={1121-1137} }

In optical tomography, conventionally the diffusion approximation to the radiative transport equation (RTE) with a constant refractive index is used to image highly scattering or turbid media. Diffusion optical tomography with a constant refractive index is rather difficult due to the exponential instability of the inverse problem. Therefore, it is beneficial to find a simple yet stable model that adequately describes the physics of radiative transport, for example, refractive index based…

## 17 Citations

Optical tomography reconstruction algorithm based on the radiative transfer equation considering refractive index: Part 2. Inverse model

- Mathematics, Computer ScienceComput. Medical Imaging Graph.
- 2013

From the reconstruct image, you can see the case of gradient refractive index agrees with the original image more closer, which shows that the reconstruct algorithm used is robust and effective.

Refractive index imaging from radiative transfer equation-based reconstruction algorithm: Fundamentals

- Physics
- 2011

Abstract We present the first reconstruction algorithm for refractive index imaging, which is based on the radiative transfer equation (RTE). An objective function is iteratively minimized to find a…

Bioluminescence tomography for media with spatially varying refractive index

- Physics
- 2009

Biomedical imaging has developed into the level of molecular imaging. Bioluminescence tomography (BLT), as an optical imaging modality, is a rapidly developing new and promising field. So far, much…

Scaling property of the diffusion equation for light in a turbid medium with varying refractive index.

- Physics, MedicineJournal of the Optical Society of America. A, Optics, image science, and vision
- 2007

It is shown that the process of photon diffusion in a turbid medium with varying refractive index and curved photon paths can be mapped to the diffusion process in a medium with straight photon paths and modified optical properties.

Approximation of Internal Refractive Index Variation Improves Image Guided Diffuse Optical Tomography of Breast

- Physics, MedicineIEEE Transactions on Biomedical Engineering
- 2010

Effective usage of image guidance by incorporating the refractive index (RI) variation in computational modeling of light propagation in tissue is investigated and a priori knowledge of the RI for the segmented regions of tissue in IG-DOT leads to more accurate estimates of optical properties.

Link between the laws of geometrical optics and the radiative transfer equation in media with a spatially varying refractive index

- Physics
- 2008

Abstract We proposed in a previous paper [J.-M. Tualle, E. Tinet, Opt. Commun. 228 (2003) 33] a modified radiative transfer equation to describe radiative transfer in a medium with a spatially…

Effects of refractive index mismatch in optical CT imaging of polymer gel dosimeters.

- Physics, MedicineMedical physics
- 2015

The results show that the proposed scheme ART-rc is able to reconstruct optical density inside the dosimeter better than the results obtained using filtered backprojection and conventional algebraic reconstruction approaches.

Sparsity Regularization in Diffuse Optical Tomography

- Physics
- 2012

The purpose of this dissertation is to improve image reconstruction in Diffuse Optical Tomography (DOT), a high contrast imaging modality that uses a near infrared light source. Because the…

Analysis of the inverse problem associated with diffuse correlation tomography

- Mathematics
- 2012

The aim of this article is to study the mathematical analysis for an inverse problem and its numerical implementation associated with diffuse correlation tomography. The coefficients of the diffusion…

Derivation of the Radiative Transfer Equation in a Medium with a Spatially Varying Refractive Index: A Review

- Physics, Chemistry
- 2012

Abstract The propagation of multiply scattered light in heterogeneous media is a subject of broad interest, especially because of its implications in biomedical optics. Many works have investigated…

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