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arXiv · 2412.01360

Photon transport through the entire adult human head

Jack Radford·Vytautas Gradauskas·Kevin J. Mitchell·Samuel Nerenberg·Ilya Starshynov·Daniele Faccio
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Abstract

Optical brain imaging technologies are promising due to their relatively high temporal resolution, portability and cost-effectiveness. However, the highly scattering nature of near-infrared light in human tissue makes it challenging to collect photons emerging from more than 4 cm below the scalp, or with source-detector separation larger than several centimeters. We explore the physical limits of photon transport in the head and show that despite an extreme attenuation of ~10^(18), we can experimentally detect light that is transmitted diametrically through the entire adult human head. Analysis of various photon migration pathways through the head also indicates how the source-detector configuration can be used to isolate photons interacting with deep regions of the brain that are inaccessible with current optical techniques.

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Jack Radford, Vytautas Gradauskas, Kevin J. Mitchell, Samuel Nerenberg, Ilya Starshynov, Daniele Faccio. 2024-12-02. Photon transport through the entire adult human head. https://arxiv.org/abs/2412.01360

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