Summary: | 碩士 === 國立中央大學 === 光電科學與工程學系 === 106 === Diffuse reflectance spectra can provide the information about absorption and scattering characteristics of substance, finding out the tissue composition and the size of granule of objects. This technique can be applied to many fields such as color measurement, color matching, remote sensing, phytology and medical detection. However, in the past, the analysis of diffuse reflectance spectra couldn’t get the difference about the different spatial distribution of diffuse reflectance spectra, but the average spectra information of entire area. If we combine the spatial information with spectra, we can get more useful information.
The biological tissue chromophores at arbitrary locations on skin are variety, which have different absorbance and reflectance depending on wavelength. By combining the spatial information with spectra, we can analyze the correlation between the absorbance and reflectance of the biological tissue chromophores, such as melanin, deoxygenated hemoglobin, oxygenated hemoglobin, β-carotene on skin.
In this article, we set up a multiple-excitation-wavelength system, which are able to select different wavelength exposures to the sample, recording the spatial distribution of absorbance and reflectance. Subsequently, establish hyperspectral images, including 2D spatial information and 1D spectral information. We take diffuse reflectance hyperspectral images of human skin, analyzing them by the formula of theoretical models. Afterwards, get the hemoglobin oxygen saturation, hemoglobin concentration and melanin concentration at different locations of the sample; use hypothesis testing to analyze the experimental data, such as the variability of hemoglobin oxygen saturation, hemoglobin concentration and melanin concentration between the blood and bloodless area on the back and palm of hand.
If we collect more data and accumulate bigger database, it can be useful for the medical diagnosis of skin disease. For instance, investigating the temporal variability of melanin concentration, which can tell whether melanin abnormally grow, can help the doctor to diagnose melanoma. The earlier the melanoma is diagnosed; the higher cure rate of skin cancer is.
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