Terahertz Spectroscopic Characterization and Imaging for Biomedical Applications

Download or read book Terahertz Spectroscopic Characterization and Imaging for Biomedical Applications written by Woon-Gi Yeo and published by . This book was released on 2015 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: Subsequently, the sensitivity of THz waves to tissue hydration is quantified through freshly-excised tissue samples. We demonstrate that cancer margins can also be accurately characterized using the differences in tissue hydration. The study is expanded to include human lung and small intestine tissues with malignant regions. New image processing algorithms are developed to enhance THz image contrast and localization of malignant areas. Furthermore, a THz polarimetry is introduced to increase sensitivity of cancer margin identification and its performance is demonstrated through full-wave simulations. Finally, human brain tissues exhibiting Alzheimer's disease are investigated to demonstrate the utility of THz imaging in Alzheimer's detection. We quantify, for the first time, measurable differences in THz reflectivity of gray and white matter, leading to accurate post-mortem diagnosis of Alzheimer's disease. Furthermore, we hypothesize that the reason for the reflectivity contrast is due to demyelination of axons. To support this hypothesis, we present full-wave electromagnetic simulations of a simplified axon model and compare the simulation data with THz measurements. Although this initial study demonstrates the efficacy of THz sensing in Alzheimer's detection, more case studies are needed to establish this finding as a viable clinical biomarker in the Alzheimer's detection in early stage.