title: Development of a near infrared multi-wavelength, multi-channel, time-resolved spectrometer for measuring brain tissue haemodynamics and metabolism.
abstract: We present a novel time domain functional near infrared spectroscopy system using a supercontinuum laser allowing us to measure the coefficient of absorption and scattering of up to 16 multiplexed wavelengths in the near infrared region. This is a four detector system that generates up to 3 mW of light for each wavelength with a narrow 2-3 nm FWHM bandwidth between 650 and 890 nm; each measurement of 16 wavelengths per channel can be performed up to a rate of 1 Hz. We can therefore quantify absolute haemoglobin changes in tissue and are currently investigating which and how many wavelengths are needed to resolve additional chromophores in tissue, such as water and the oxidation state of cytochrome-c-oxidase.
authors.affiliation: Department of Medical Physics & Bioengineering, University College London, Malet Place Eng. Building, Gower Street, London, WC1E 6BT, UK. luke.dunne.10@ucl.ac.uk.
authors.forename: Luke
authors.initials: L
authors.lastname: Dunne
authors.affiliation: Department of Medical Physics & Bioengineering, University College London, Malet Place Eng. Building, Gower Street, London, WC1E 6BT, UK.
authors.forename: Jem
authors.initials: J
authors.lastname: Hebden
authors.affiliation: Department of Medical Physics & Bioengineering, University College London, Malet Place Eng. Building, Gower Street, London, WC1E 6BT, UK.
authors.forename: Ilias
authors.initials: I
authors.lastname: Tachtsidis
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism* / Q000502:physiology; D006439:Hemodynamics; D006454:Hemoglobins / Q000378:metabolism; D019265:Spectroscopy, Near-Infrared / Q000295:instrumentation / Q000379:methods*; D013552:Swine
chemical_list: D006454:Hemoglobins
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