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This study shows the influence that the scattering phase function of Intralipid has on reflectance spectra. Significant spectral remission changes result from simply changing the reflectance probe geometries utilized in tissue spectroscopy research.

Combining nine discrete wavelengths for NIR Spectroscopy with MRI allows quantitative estimation of breast cancers in contrast scans. Combinations of PMT and spectrometers are used with validation in phantoms, normal subjects and pilot human cancers.

The design of a new hybrid breast optical imaging signal detection system is described using photodiodes together with PMTs. The goal of this design is to better quantify chromophores in tissue with a wider wavelength band.

Employing multiple time-bins in the image reconstruction of a time-domain fluorescence tomography dataset provides improved spatial resolution and contrast. Furthermore, these gains can be used to minimize tissue sampling and reduce imaging duration

A comparison of the Diffusion approximation and a Monte Carlo approach in the context of small animal fluorescence tomography is presented, forming a foundation for hybrid approaches to improve accuracy of fluorescence tomography.

‘1click’ toolbox for tetrahedral mesh generation is presented that uses stack of 2D images with multiple regions. GUI-based approach to quality inspection and optimization of mesh bridges the gap from volume imaging to mesh generation.

Raman signal is measured through a tomography set-up with 8 distinct spectrometers allowing for increased spectral resolution. Reconstructed images show good localization and contrast of Raman signal to background for Teflon inclusions within gelatin-based phantoms.

A scanning full-spectrum imaging system was used to image and analyze the spectral morphology of resected breast cancer specimens, to evaluate the optimum parameters from which to diagnose involvement of cancer in the margins. Article not available.

This work studies an approach to combine tomosynthesis breast imaging with near infrared spectroscopy to determine tissue chromphore concentrations using spatial prior tomosythesis data and correlated scatter information.

It is shown that an analytic expression of fluorescence ratio detection can provide a direct estimate of depth in multi-spectral sub-surface imaging. This is supported by preliminary fluorescence data acquired with a broad-beam multi-spectral system.

A broadband scanning scatter spectroscopy imaging system has been developed to allow intra-operative assessment of lumpectomy tumor margins based on localized tissue scatter measures. Results from preliminary phantom measurements are discussed.

A surface-shrinking algorithm is demonstrated for automated source position localization one scattering depth into discretized simulation domains, in near-infrared imaging. The algorithm allows users to accurately place source fiber locations with minimal guidance.

A novel hybrid method combining 3-D FE and BE techniques has been implemented for modeling light diffusion combining homogeneous and heterogeneous regions. Results show less than 1% difference in boundary data between the different models.

Accuracy and resolution of image guided near-infrared spectroscopy for breast imaging is characterized through simulations of varying contrasts and sizes. Results show errors of %4 for sizes greater than 20mm, but higher for smaller sizes.

The dynamic vascular change in the breast due to the pressure-displacement kinetics and inspired gas dynamics are imaged by a frequency domain tomographic system with 20 second temporal resolution.

Optimized bands of wavelengths in spectral optical imaging is presented showing improvement in cross talk between parameters. A normalization technique is presented which creates a more uniform update within a spectral image reconstruction model.

A NIR diffuse optical tomography system with spectrally-encoded sources at two wavelength bands allows simultaneous detection at high speed. It works with MR to provide images of high-contrast, fast changes in tissue oxygen saturation.

An automated ultrasound-guided fluorescence tomography system was created to image the Protoporphyrin IX production of subcutaneous tumors in vivo. Negative production and positive production tumors were compared to validate the system capability.

A new approach for steady-state photon diffusion modeling associated with a cylindrical applicator boundary for trans-luminal optical tomography was evaluated numerically and experimentally. In the diffusion regime the theoretical predictions agree well with experimental findings.

The diagnostic potential of MRI-coupled fluorescence tomography of epidermal growth factor receptor (EGFR) status in brain cancer was demonstrated. Perfect diagnostic performance was observed between mice inoculated with EGFR(+) or EGFR(-) tumor cells.

Non-contact fluorescence tomography of small animals needs to be automated to balance gain control and laser intensity avoiding saturation or noisy signals. System workflow is identified and the concept of automatic exposure control is tested.

Model based image reconstruction in Optical and Molecular imaging is rapidly becoming an optimal method due to the flexibility and robustness of this method to problem specific cases. An online imaging and Finite Element modeling tool for optical imaging has been developed which allows the user to run problem specific cases, as well as providing an online tutorial for light propagation in tissue. This online package, based on NIRFAST is presented and is being made available to users worldwide to allow further development of this novel imaging technique.

MRI-guided near infrared spectroscopy has been implemented with a user-positioned three-dimensional fiber interface, allowing acquisition of multiple planes of data and targeting of suspect regions from within the MR exam.

A reflectance imaging system acquired spectra from breast tissue and scattering parameters were linked to morphological features identified by a pathologist in 75 ROIs. A KNN algorithm discriminated between tissue pathologies with nearly 84% accuracy.

Detailed singular mode analysis is used to define the spatial resolution of whole-body fluorescence tomography instruments. This proposed methodology provides image-space information that is complementary to singular values.

Simulations were completed to determine the effect of the propagation of Raman signal through a rat tibia. Reconstructed data show a shift in the Raman Spectra of less than 1nm as compared to original signal.