title: Interpretation of principal components of the reflectance spectra obtained from multispectral images of exposed pig brain.
abstract: The spatial variation in reflectance such as the blood-vessel pattern can be observed in the image of cerebral cortex. This spatial variation is mainly caused by the difference in concentrations of oxy- and deoxyhemoglobin in the tissue. We analyze the reflectance spectra obtained from multispectral images of pig cortex by principal component analysis to extract information that relates to physiological parameters such as the concentrations of oxy- and deoxyhemoglobin and physical parameters such as mean optical path length. The light propagation in a model of exposed pig cortex is predicted by Monte Carlo simulation to estimate the interpretation of physiological and physical meanings of the principal components. The spatial variance of reflectance spectra of the pig cortex can be approximately described by the first principal component. The first principal component reflects the spectrum of hemoglobin in the cortical tissue multiplied by the mean optical path length. These results imply that the wavelength dependence of mean optical path length can be experimentally estimated from the first principal component of the reflectance spectra obtained from multispectral image of cortical tissue.
authors.affiliation: Keio University, Department of Electronics and Electrical Engineering, 3-14-1, Hiyoshi, Kohoku-ku, Yokohama, 223-8522, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Yokoyama
authors.forename: Motoshi
authors.initials: M
authors.lastname: Watanabe
authors.forename: Yohei
authors.initials: Y
authors.lastname: Watanbe
authors.forename: Eiji
authors.initials: E
authors.lastname: Okada
mesh_terms: D000818:Animals; D002540:Cerebral Cortex / Q000378:metabolism / Q000502:physiology* / Q000528:radiation effects; D003198:Computer Simulation; D006454:Hemoglobins / Q000378:metabolism; D016018:Least-Squares Analysis; D008027:Light; D008959:Models, Neurological; D009010:Monte Carlo Method; D010108:Oxyhemoglobins / Q000378:metabolism; D025341:Principal Component Analysis; D012542:Scattering, Radiation; D013057:Spectrum Analysis; D013552:Swine; D014018:Tissue Distribution
chemical_list: D006454:Hemoglobins; D010108:Oxyhemoglobins; C100003:deoxyhemoglobin