Abstract: A method for detecting death process of a cell or tissue of a living subject. In one embodiment, the method includes the steps of illuminating the cell or tissue of the living subject with a coherent light, collecting fluorescent light returned from the illuminated cell or tissue of the living subject, identifying a NAD(P)H peak of a spectrum of the collected fluorescent light with a wavelength, ?peak, and obtaining the intensity of the NAD(P)H peak of the spectrum of the collected fluorescent light substantially corresponding to the wavelength ?peak. These steps are repeated at sequential stages until the intensity of the NAD(P)H peak of the spectrum at a current stage is less than the intensity of the NAD(P)H peak of the spectrum at an earlier stage immediately prior to the current stage so as to detect death process of the cell of the living subject at the current stage using the intensity of the NAD(P)H peak of the spectrum.

Abstract: A method for differentiating malignant in vivo liver tissues from normal in vivo liver tissues of a living subject includes the steps of: (a) illuminating a first area and a second area of in vivo liver tissues of the living subject with a first excitation light, (b) measuring an intensity of fluorescent light emitted from each of the first area and the second area of in vivo liver tissues in response to the first excitation light as a function of wavelength so as to obtain a first and a second fluorescent spectra, respectively, (c) illuminating the first area and the second area of in vivo liver tissues with a second excitation light, (d) measuring an intensity of diffuse light reflected by each of the first area and the second area of in vivo liver tissues in response to the second excitation light as a function of wavelength so as to obtain a first and a second diffused reflectance spectra, respectively, and (e) identifying one of the first area and the second area of in vivo liver tissues as malignant liv

Abstract: A method for detecting death process of a cell or tissue of a living subject. In one embodiment, the method includes the steps of illuminating the cell or tissue of the living subject with a coherent light, collecting fluorescent light returned from the illuminated cell or tissue of the living subject, identifying a NAD(P)H peak of a spectrum of the collected fluorescent light with a wavelength, ?peak, and obtaining the intensity of the NAD(P)H peak of the spectrum of the collected fluorescent light substantially corresponding to the wavelength ?peak. These steps are repeated at sequential stages until the intensity of the NAD(P)H peak of the spectrum at a current stage is less than the intensity of the NAD(P)H peak of the spectrum at an earlier stage immediately prior to the current stage so as to detect death process of the cell of the living subject at the current stage using the intensity of the NAD(P)H peak of the spectrum.

Abstract: An apparatus and method for detecting radiation damage in an area of brain tissues, where the area of brain tissues has at least a first region containing brain tissues damaged from radiation exposure and a second region containing no brain tissues damaged from radiation exposure. In one embodiment, the method includes the steps of illuminating in vivo the area of brain tissues with a coherent light at an incident wavelength, &lgr;0, between 330 nm and 360 nm, collecting electromagnetic emission returned from the illuminated brain tissues, and identifying a first peak of intensity of the collected electromagnetic emission at a first wavelength, &lgr;1, and a second peak of intensity of the collected electromagnetic emission at a second wavelength, &lgr;2, wherein &lgr;0, &lgr;1, and &lgr;2 satisfy the following relationship of &lgr;1>&lgr;2>&lgr;0.

Abstract: Tissue types (e.g. tumorous or normal) are determined using optical spectroscopy. Autofluorescence and diffuse reflectance spectra are generated by separately illuminating a tissue surface area with monochromatic light and white light. A peak in autofluorescence intensity (F) is provided around 460 nm from both from normal and tumorous human brain tissue with 337 nm monochromatic light excitation. Separation between white/gray matter and brain tumors is provided by certain combined F-Rd spectrum numerical values, especially certain ratios of F and Rd between 400 nm-600 nm. Numerical values based on certain combinations of unequal exponential powers of F and Rd are essentially unaffected by the superficial blood contamination. In addition, diffuse reflectance intensity (Rd) between 650 nm and 800 nm from white/gray matter was significantly stronger than that from primary and secondary brain tumors and is used with the combined spectrum numerical value to enhance accurate determinations.

Abstract: Optical spectroscopy for brain tumor demarcation was investigated in this study. Fluorescence and diffuse reflectance spectra were measured from normal and tumorous human brain tissues in vitro. A fluorescence peak was consistently observed around 460 nm (±10 nm) emission from both normal and tumorous brain tissues using 337 nm excitation. Intensity of this fluorescence peak (F460) from normal brain tissues was greater than that from primary brain tumorous tissues. In addition, diffuse reflectance (Rd) between 650 nm and 800 nm from white matter was significantly stronger than that from primary and secondary brain tumors. A good separation between gray matter and brain tumors was found using the ratio of F460 and Rd at 400 nm-600 nm. Two empirical discrimination algorithms based on F (400 nm-600 nm), Rd (600 nm-800 nm), and F (400 nm-600 nm)/Rd (400 nm-600 nm) were developed. These algorithms yielded an average sensitivity and specificity of 96% and 93%, respectively.