title: Multispectral imaging of absorption and scattering properties of in vivo exposed rat brain using a digital red-green-blue camera.
abstract: In order to estimate multispectral images of the absorption and scattering properties in the cerebral cortex of in vivo rat brain, we investigated spectral reflectance images estimated by the Wiener estimation method using a digital RGB camera. A Monte Carlo simulation-based multiple regression analysis for the corresponding spectral absorbance images at nine wavelengths (500, 520, 540, 560, 570, 580, 600, 730, and 760 nm) was then used to specify the absorption and scattering parameters of brain tissue. In this analysis, the concentrations of oxygenated hemoglobin and that of deoxygenated hemoglobin were estimated as the absorption parameters, whereas the coefficient a and the exponent b of the reduced scattering coefficient spectrum approximated by a power law function were estimated as the scattering parameters. The spectra of absorption and reduced scattering coefficients were reconstructed from the absorption and scattering parameters, and the spectral images of absorption and reduced scattering coefficients were then estimated. In order to confirm the feasibility of this method, we performed in vivo experiments on exposed rat brain. The estimated images of the absorption coefficients were dominated by the spectral characteristics of hemoglobin. The estimated spectral images of the reduced scattering coefficients had a broad scattering spectrum, exhibiting a larger magnitude at shorter wavelengths, corresponding to the typical spectrum of brain tissue published in the literature. The changes in the estimated absorption and scattering parameters during normoxia, hyperoxia, and anoxia indicate the potential applicability of the method by which to evaluate the pathophysiological conditions of in vivo brain due to the loss of tissue viability.
authors.affiliation: Tokyo University of Agriculture & Technology, Graduate School of Bio-Application & Systems Engineering, Koganei, Tokyo 184-8588, Japan.
authors.forename: Keiichiro
authors.initials: K
authors.lastname: Yoshida
authors.affiliation: Tokyo University of Agriculture & Technology, Graduate School of Bio-Application & Systems Engineering, Koganei, Tokyo 184-8588, Japan.
authors.forename: Izumi
authors.initials: I
authors.lastname: Nishidate
authors.affiliation: Tokyo University of Agriculture & Technology, Graduate School of Bio-Application & Systems Engineering, Koganei, Tokyo 184-8588, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Ishizuka
authors.affiliation: National Defense Medical College Research Institute, Division of Biomedical Information Sciences, Tokorozawa, Saitama 359-8513, Japan.
authors.forename: Satoko
authors.initials: S
authors.lastname: Kawauchi
authors.affiliation: National Defense Medical College Research Institute, Division of Biomedical Information Sciences, Tokorozawa, Saitama 359-8513, Japan.
authors.forename: Shunichi
authors.initials: S
authors.lastname: Sato
authors.affiliation: Yamagata University, Graduate School of Science and Engineering, Yonezawa, Yamagata 992-8510, Japan.
authors.forename: Manabu
authors.initials: M
authors.lastname: Sato
mesh_terms: D000818:Animals; D001921:Brain / Q000473:pathology*; D002540:Cerebral Cortex / Q000473:pathology; D003198:Computer Simulation; D003201:Computers; D003952:Diagnostic Imaging / Q000379:methods; D006439:Hemodynamics; D006454:Hemoglobins / Q000737:chemistry*; D000860:Hypoxia / Q000473:pathology; D007091:Image Processing, Computer-Assisted; D001239:Inhalation; D008027:Light; D008297:Male; D009010:Monte Carlo Method; D010100:Oxygen / Q000737:chemistry; D010101:Oxygen Consumption; D051381:Rats; D017208:Rats, Wistar; D012044:Regression Analysis; D012542:Scattering, Radiation; D013057:Spectrum Analysis / Q000379:methods*
chemical_list: D006454:Hemoglobins; D010100:Oxygen