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Author Li, Changqing
Title Breast cancer detection with diffuse optical tomography
Descript 192 p
Note Source: Dissertation Abstracts International, Volume: 68-01, Section: B, page: 0436
Adviser: Huabei Jiang
Thesis (Ph.D.)--University of Florida, 2006
Diffuse optical tomography (DOT) is emerging as a potential imaging technique for breast cancer detection. Compared with the routine x-ray mammography which gives only the structural images of breast tissue, DOT provides not only the structural information, but also the functional images including oxy-hemoglobin, deoxy-hemoglobin, lipid and water content as well as the morphological images including nucleus size and volume fraction. The goal of this thesis study is to obtain these structural, functional and morphological contents of breast tissue using a multi-spectral DOT reconstruction approach. This study involves imaging hardware implementation and software development necessary for achieving the goal. The imaging system and reconstruction software implemented are tested and evaluated using extensive simulations, tissue-like phantom experiments and in vivo clinical studies
A compact diffuse optical tomography system, specifically designed for breast imaging, is constructed. The system consists of 64 silicon photodiode detectors, 64 excitation points, and 10 diode lasers in the near-infrared region, allowing multi-spectral, three-dimensional optical imaging of breast tissue. The system performance and optimization through a calibration procedure are detailed. The system is evaluated using tissue-like phantom and clinical experiments. Quantitative 2D and 3D images of absorption and reduced scattering coefficients 15 are obtained from these experimental data. Two methods, dual mesh method and source intensity optimization method, are implemented for improved 3D DOT reconstructions and validated by tissue-like phantom experiments
Reconstruction algorithms for obtaining tissue morphological images are described. Quantitative images are successfully reconstructed in terms of the size, location and tissue morphology of target from both tissue phantom and in vivo data. Initial clinical results show that the scattering particle size and volume fraction at cellular level are potential new parameters that could be used for differentiating malignant from benign lesions
A new method, namely spectrally constrained DOT, is also developed to directly reconstruct tissue chromophore concentrations and volume fraction of scattering particles simultaneously. The absorption extinction coefficient spectra of oxy-hemoglobin, deoxy-hemoglobin as well as the absorption spectrum of water are measured using a mixture of human blood and Intralipid solution with the imaging system developed. The quality of the reconstructed images is improved substantially when the measured spectra are utilized, compared with that of the images recovered with the spectra obtained from the literature
School code: 0070
Host Item Dissertation Abstracts International 68-01B
Subject Engineering, Biomedical
0541
Alt Author University of Florida
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