Light Dosing and Tissue Penetration: It Is Complicated.

Raymond Lanzafame

doi:10.1089/photob.2020.4843

Abstract

Light Dosing and Tissue Penetration: It Is Complicated.

Highlights

This simple real-world observation arguably flies in the face of decades of arguments and a large number of experiments and publications presented as evidence to support or refute the utility of light-emitting diodes (LEDs), that is, lasers, laser diodes, and other light sources for photobiomodulation (PBM) or other applications
Versus lack thereof, and so called high intensity and treatises on ‘‘Laser versus LED’’ and other variations have muddied understanding of the fact that when the proper wavelengths of light are applied to an appropriate and receptive tissue at the proper parameters, the observed effects of photobiomodulation therapy (PBMT) accrue.[1]. These issues are further compounded by the selection and use of light wavelengths for PBMT based on their ‘‘tissue penetration depth’’ primarily rather than matching wavelengths with the spectral absorption curves of the target chromophores
Some have argued that all cells and tissues should be responsive to PBMT if the proper wavelengths and dosing parameters are delivered, since mitochondria and cytochrome c oxidase, a primary PBM target photoacceptor, exist in eukaryotic cells

Summary

Introduction

This simple real-world observation arguably flies in the face of decades of arguments and a large number of experiments and publications presented as evidence to support or refute the utility of light-emitting diodes (LEDs), that is, lasers, laser diodes, and other light sources for photobiomodulation (PBM) or other applications. These issues are further compounded by the selection and use of light wavelengths for PBMT based on their ‘‘tissue penetration depth’’ primarily rather than matching wavelengths with the spectral absorption curves of the target chromophores.

Results

Conclusion