Share Email Print

Proceedings Paper

Trans-cranial infrared laser stimulation induces hemodynamic and metabolic response measured by broadband near infrared spectroscopy in vivo on human forehead (Conference Presentation)
Author(s): Xinlong Wang; Sahil Sunil Nalawade; Divya Dhandapani Reddy; Fenghua Tian; F. Gonzalez-Lima; Hanli Liu

Paper Abstract

Transcranial infrared laser stimulation (TILS) uses infrared light (lasers or LEDs) for nondestructive and non-thermal photobiomodulation on the human brain. Although TILS has shown its beneficial effects to a variety of neurological and psychological conditions, its physiological mechanism remains unknown. Cytochrome-c-oxidase (CCO), the last enzyme in the electron transportation chain, is proposed to be the primary photoacceptor of this infrared laser. In this study, we wish to validate this proposed mechanism. We applied 8 minutes in vivo TILS on the right forehead of 11 human participants with a 1064-nm laser. Broad-band near infrared spectroscopy (bb-NIRS) from 740-900nm was also employed near the TILS site to monitor hemodynamic and metabolic responses during the stimulation and 5-minute recovery period. For rigorous comparison, we also performed similar 8-min bb-NIR measurements under placebo conditions. A multi-linear regression analysis based on the modified Beer-Lambert law was performed to estimate concentration changes of oxy-hemoglobin (Δ[HbO]), deoxy-hemoglobin (Δ[Hb]), and cytochrome-c-oxidase (Δ[CCO]). We found that TILS induced significant increases of [CCO], [HbO] and a decrease of [Hb] with dose-dependent manner as compared with placebo treatments. Furthermore, strong linear relationships or interplays between [CCO] versus [HbO] and [CCO] versus [Hb] induced by TILS were observed in vivo for the first time. These relationships have clearly revealed close coupling/relationship between the hemodynamic oxygen supply and blood volume versus up-regulation of CCO induced by photobiomodulation. Our results demonstrate the tremendous potential of bb-NIRS as a non-invasive in vivo means to study photobiomodulation mechanisms and perform treatment evaluations of TILS.

Paper Details

Date Published: 19 April 2017
PDF: 1 pages
Proc. SPIE 10062, Optical Interactions with Tissue and Cells XXVIII, 100620M (19 April 2017); doi: 10.1117/12.2253496
Show Author Affiliations
Xinlong Wang, The Univ. of Texas at Arlington (United States)
Sahil Sunil Nalawade, The Univ. of Texas at Arlington (United States)
Divya Dhandapani Reddy, The Univ. of Texas at Arlington (United States)
Fenghua Tian, The Univ. of Texas at Arlington (United States)
F. Gonzalez-Lima, The Univ. of Texas at Austin (United States)
Hanli Liu, The Univ. of Texas at Arlington (United States)

Published in SPIE Proceedings Vol. 10062:
Optical Interactions with Tissue and Cells XXVIII
E. Duco Jansen; Hope Thomas Beier, Editor(s)

© SPIE. Terms of Use
Back to Top