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In this study, we develop an analytical based simulation method to determine laser parameters such as laser power and its duration for laser induced thermal ablation. This method utilizes two important physical approaches to model i) the light propagation and ii) the change in temperature due to the laser absorption in turbid media. First, the photon density is obtained analytically from the solution of the diffusion equation by deriving a special Greens’ function. Next, the Pennes bio-heat equation is solved analytically for a source term consisting of the product of the photon density and the optical absorption coefficient. Our approach is validated with the results obtained by Finite Element Method (FEM) and experimental results acquired from the gold-nanoparticle embedded phantom.

Photo-Magnetic Imaging (PMI) is a novel diffuse optical imaging technique that yields high resolution optical absorption images. It is based on the measurement of the temperature increase of a given medium after its illumination with a near-infrared laser using Magnetic Resonance Thermometry (MRT). In this paper, we present the first multi-wavelengths PMI system able to provide oxy- and deoxyhemoglobin concentration maps with high spatial and quantitative accuracy.

We introduce a new Photo-Magnetic Imaging image reconstruction algorithm that uses analytical methods to solve both its forward and inverse problem, making it 33 times faster than a single iteration of our previous FEM-based algorithm.

Laser induced thermal ablation is a minimally invasive alternative to conventional surgery and can provide faster recovery times as well as reduction in complication rates. In this study, our purpose is to develop a simulation tool for therapy planning to determine important laser parameters that govern the magnitude of temperature rise and its duration in the tissue. This tool is based on the use of a new analytical approach to model laser induced temperature in turbid media. First, the diffusion equation is used for the light propagation and a comprehensive solution is derived analytically by obtaining a special Greens’ function. Next, the heat equation is also solved analytically for a source term given by the product of the solution of the diffusion equation and the local optical absorption. The results obtained with our theoretical model are successfully validated using experimental data.

We present a high-resolution fluorescence imaging technique based on the use of in-vivo temperature sensitive ICG loaded pluronic nanocapsules and the synergistic combination of two imaging techniques: Fluorescence Tomography (FT) and High Intensity Focused Ultrasound (HIFU).

Optical tomography at organ level is challenging due to highly scattering nature of the tissue. We have developed a novel true multimodality imaging technique, namely Photo-Magnetic Imaging (PMI), which provides superior spatial resolution and high quantitative accuracy even in thick tissue.

We describe a novel approach termed "temperature-modulated fluorescence tomography" that can acquire fluorescence images at focused ultrasound resolution. By utilizing recently emerged temperature sensitive fluorescence contrast agents, this technique provides fluorescence images with high spatial resolution.

In this paper, we present a novel imaging technique, namely Photo-Magnetic Imaging (PMI), which overcomes the limitation of pure optical imaging and provides optical contrast at MRI spatial resolution.

A priori information can be used to guide near-infrared diffuse optical tomography reconstruction and improve quantification. The goal of this study is to develop a hands-free, fully automatic US-DOT system for quantitative whole breast imaging.

In this study, a hybrid MR-frequency domain fluorescence tomography (FT) is developed. The phantom studies show that the anatomical images from MRI improve reconstruction of both fluorescence concentration and lifetime parameters significantly.

It is difficult to cross-validate the parameters measured by different modalities. Our in vivo small animal study is the first to validate a true multi-modality system (combined MRI-DOT system) with a true multi-modality contrast agent.

In both absorption and fluorescence mode, in vivo optical tomography is challenging due to highly scattering nature of the tissue. We have developed dual and tri-modality systems that can provide quantitatively accurate cross-sectional optical images using complementary information from other imaging modalities.

We describe the implementation of a multi-modality imaging platform, which integrates a multi-frequency, multi-wavelength optical tomography system with a 3.0 T MRI scanner to obtain the additional diagnostic information of suspicious breast lesions.

Molecular disposition of water has been measured non-invasively in the NIR using Diffuse Optical Spectroscopy in thick tissues. The water binding state has provided significant pathological information of breast tissues.

The design and implementation of a polarization sensitive OCT system is described. An iterative algorithm is used to calculate the Jones matrix of the sample. The performance of the system is evaluated with muscle samples.

Use of multi-frequency DOT for reconstruction of optical properties is investigated. Choosing appropriate frequency values by considering system noise and using multi-parameter Tikhonov regularization, improvement is demonstrated using phantom data with multi-frequency reconstruction.

We developed a simultaneous MR-DOT system for small animal imaging. MRI image is used as a-priori information for DOT reconstruction providing accurate geometry and boundary condition. Performance is demonstrated in-vivo with ENU tumor bearing rat.

The goal of this study is to develop a dynamic DOT system as an adjunct to MRI. Such a combined system may provide complementary information and lead to increased specificity in breast cancer characterization.

We present a quantitative comparison of lipid and water signals obtained from broadband Diffuse Optical Spectroscopy (DOS) and Magnetic Resonance Imaging (MRI) of emulsion tissue phantoms.

The dynamics of optical contrast agents are measured in an adenocarcinoma rat tumor model using a combined frequency-domain and steady-state optical technique. Compartmental modeling of contrast agent dynamics allows quantification of physiologic parameters such as capillary permeability and blood flow. Optically-derived parameters are compared to those measured by contrast-enhanced MRI.

We studied the physiological changes in animal model tumors by co-registration of near-infrared spectroscopy and MRI. T2 weighted and Gd-DTPA enhanced MRI images correlate with changes observed in Hb, HbO2 and water concentrations measured by near-infrared spectroscopy.