Jing-Wei SuCheng-Ying ChouKung-Bin SungKUNG-BIN SUNG2018-09-102018-09-102014-01http://scholars.lib.ntu.edu.tw/handle/123456789/388920Three-dimensional (3D) refractive index (RI) microscopy is an emerging and useful technique for investigating the inner structures of biological cells or tissues and their correlation with pathological state such as cancerous progression. During progression of epithelial dysplasia which is a precursor of many cancers, changes in nuclear structure and tissue architecture could lead to changes in light scattering properties that have the potential to be in vivo biomarkers for precancer or early cancer. To investigate light scattering properties of normal and precancerous epithelial tissues, we have developed a 3D RI microscopy technique called digital homographic microtomography (DHμT). The axial resolution of the DHμT is improved from 1.1 μm to 0.35 μm by scanning the illumination angle with a circular pattern. Three reconstruction algorithms have been implemented including conventional filtered back projection, optical diffraction tomography (ODT) with direct Fourier interpolation, and ODT with regularization. Compressive sensing capability is demonstrated using the ODT with regularization method. The DHμT technique is applied to measure 3D RI images of normal and cancerous epithelial cell lines and calculate light scattering properties of single cells and synthesized tissue. Cancerous cells show higher total scattering cross section and backscattering cross section than normal cells. Results from synthesized tissue slices indicate up to two-times increase in the scattering coefficient when the tissue changes from normal to high-grade dysplasia. This novel approach for characterizing the scattering coefficient of epithelial tissue is rigorous and could facilitate the development of non-invasive optical techniques for diagnostic, monitoring and therapeutic purposes. ? 2014 Nova Science Publishers, Inc.[SDGs]SDG3Cell culture; Cells; Cytology; Diseases; Histology; Light scattering; Optical systems; Refractive index; Tissue; Tomography; Backscattering cross section; Direct Fourier interpolation; Filtered back projection; Non-invasive optical techniques; Optical diffraction tomography; Reconstruction algorithms; Scattering co-efficient; Total scattering cross sections; Tissue engineeringjournal article2-s2.0-84940252816