title: Noninvasive determination of absorption and reduced scattering coefficients of adult heads by time-resolved reflectance measurements for functional near infra-red spectroscopy.
abstract: Absorption and reduced scattering coefficients (μ(a) and μ'(s)) of adult heads have been noninvasively determined by time-resolved reflectance measurements. The finite difference time domain (FDTD) analysis was used to calculate time-resolved reflectance from realistic adult head models with brain grooves containing a non-scattering layer. In vivo time-resolved reflectances of human heads were measured by a system composed of a time-correlated single photon counter and a diode laser. By minimizing the objective functions that compare theoretical and experimental time resolved reflectances, μ(a) and μ'(s) of brain were determined. It became clear that time-resolved measurements have enough sensitivity to determine both μ(a) and μ'(s) for superficial tissues, gray matter and white matter, except μ(s) for white matter.
authors.forename: T
authors.initials: T
authors.lastname: Tanifuji
authors.forename: L
authors.initials: L
authors.lastname: Wang
mesh_terms: D066128:Gray Matter / Q000502:physiology*; D006257:Head / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D019265:Spectroscopy, Near-Infrared; D066127:White Matter / Q000502:physiology*; D055815:Young Adult