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Determining changes in NIR absorption using a layered model of the human head.

J Steinbrink·H Wabnitz·H Obrig·A Villringer·H Rinneberg
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Abstract

A theoretical approach is presented to determine absorption changes in different compartments of a layered structure from distributions of times of flight of photons. In addition resulting changes in spatial profiles of time-integrated intensity and mean time of flight are calculated. The capability of a single-distance, time-domain method to determine absorption changes with depth resolution is tested on a layered phantom. We apply this method to in vivo measurements on the human head (motor stimulation, Valsalva manoeuvre) and introduce a small-sized time-domain experimental set-up suitable for bedside monitoring.

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BrainComputer SimulationHeadHumansMonte Carlo MethodMotor ActivityPhantoms, ImagingPhotonsSpectroscopy, Near-InfraredValsalva ManeuverJournal ArticleResearch Support, Non-U.S. Gov't

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J Steinbrink, H Wabnitz, H Obrig, A Villringer, H Rinneberg. 2001. Determining changes in NIR absorption using a layered model of the human head.. https://doi.org/10.1088/0031-9155%2F46%2F3%2F320

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