Near-infrared photonic energy penetration: can infrared phototherapy effectively reach the human brain?

Theodore A Henderson,1,2 Larry D Morries2 1The Synaptic Space, Centennial, CO, USA; 2Neuro-Laser Foundation, Lakewood, CO, USA Abstract: Traumatic brain injury (TBI) is a growing health concern effecting civilians and military personnel. Research has yielded a better understanding of the pathophys...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Henderson TA, Morries LD
Formato:	article
Lenguaje:	EN
Publicado:	Dove Medical Press 2015
Materias:	Neurosciences. Biological psychiatry. Neuropsychiatry RC321-571 Neurology. Diseases of the nervous system RC346-429
Acceso en línea:	https://doaj.org/article/e63e208af69d46a8aef596110243c320
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:e63e208af69d46a8aef596110243c320
record_format	dspace
spelling	oai:doaj.org-article:e63e208af69d46a8aef596110243c3202021-12-02T03:38:42ZNear-infrared photonic energy penetration: can infrared phototherapy effectively reach the human brain?1178-2021https://doaj.org/article/e63e208af69d46a8aef596110243c3202015-08-01T00:00:00Zhttp://www.dovepress.com/near-infrared-photonic-energy-penetration-can-infrared-phototherapy-ef-peer-reviewed-article-NDThttps://doaj.org/toc/1178-2021Theodore A Henderson,1,2 Larry D Morries2 1The Synaptic Space, Centennial, CO, USA; 2Neuro-Laser Foundation, Lakewood, CO, USA Abstract: Traumatic brain injury (TBI) is a growing health concern effecting civilians and military personnel. Research has yielded a better understanding of the pathophysiology of TBI, but effective treatments have not been forthcoming. Near-infrared light (NIR) has shown promise in animal models of both TBI and stroke. Yet, it remains unclear if sufficient photonic energy can be delivered to the human brain to yield a beneficial effect. This paper reviews the pathophysiology of TBI and elaborates the physiological effects of NIR in the context of this pathophysiology. Pertinent aspects of the physical properties of NIR, particularly in regards to its interactions with tissue, provide the background for understanding this critical issue of light penetration through tissue. Our recent tissue studies demonstrate no penetration of low level NIR energy through 2 mm of skin or 3 cm of skull and brain. However, at 10–15 W, 0.45%–2.90% of 810 nm light penetrated 3 cm of tissue. A 15 W 810 nm device (continuous or non-pulsed) NIR delivered 2.9% of the surface power density. Pulsing at 10 Hz reduced the dose of light delivered to the surface by 50%, but 2.4% of the surface energy reached the depth of 3 cm. Approximately 1.22% of the energy of 980 nm light at 10–15 W penetrated to 3 cm. These data are reviewed in the context of the literature on low-power NIR penetration, wherein less than half of 1% of the surface energy could reach a depth of 1 cm. NIR in the power range of 10–15 W at 810 and 980 nm can provide fluence within the range shown to be biologically beneficial at 3 cm depth. A companion paper reviews the clinical data on the treatment of patients with chronic TBI in the context of the current literature. Keywords: infrared, traumatic brain injury, TBI, class IV laser, sleep disturbance, depressionHenderson TAMorries LDDove Medical PressarticleNeurosciences. Biological psychiatry. NeuropsychiatryRC321-571Neurology. Diseases of the nervous systemRC346-429ENNeuropsychiatric Disease and Treatment, Vol 2015, Iss default, Pp 2191-2208 (2015)
institution	DOAJ
collection	DOAJ
language	EN
topic	Neurosciences. Biological psychiatry. Neuropsychiatry RC321-571 Neurology. Diseases of the nervous system RC346-429
spellingShingle	Neurosciences. Biological psychiatry. Neuropsychiatry RC321-571 Neurology. Diseases of the nervous system RC346-429 Henderson TA Morries LD Near-infrared photonic energy penetration: can infrared phototherapy effectively reach the human brain?
description	Theodore A Henderson,1,2 Larry D Morries2 1The Synaptic Space, Centennial, CO, USA; 2Neuro-Laser Foundation, Lakewood, CO, USA Abstract: Traumatic brain injury (TBI) is a growing health concern effecting civilians and military personnel. Research has yielded a better understanding of the pathophysiology of TBI, but effective treatments have not been forthcoming. Near-infrared light (NIR) has shown promise in animal models of both TBI and stroke. Yet, it remains unclear if sufficient photonic energy can be delivered to the human brain to yield a beneficial effect. This paper reviews the pathophysiology of TBI and elaborates the physiological effects of NIR in the context of this pathophysiology. Pertinent aspects of the physical properties of NIR, particularly in regards to its interactions with tissue, provide the background for understanding this critical issue of light penetration through tissue. Our recent tissue studies demonstrate no penetration of low level NIR energy through 2 mm of skin or 3 cm of skull and brain. However, at 10–15 W, 0.45%–2.90% of 810 nm light penetrated 3 cm of tissue. A 15 W 810 nm device (continuous or non-pulsed) NIR delivered 2.9% of the surface power density. Pulsing at 10 Hz reduced the dose of light delivered to the surface by 50%, but 2.4% of the surface energy reached the depth of 3 cm. Approximately 1.22% of the energy of 980 nm light at 10–15 W penetrated to 3 cm. These data are reviewed in the context of the literature on low-power NIR penetration, wherein less than half of 1% of the surface energy could reach a depth of 1 cm. NIR in the power range of 10–15 W at 810 and 980 nm can provide fluence within the range shown to be biologically beneficial at 3 cm depth. A companion paper reviews the clinical data on the treatment of patients with chronic TBI in the context of the current literature. Keywords: infrared, traumatic brain injury, TBI, class IV laser, sleep disturbance, depression
format	article
author	Henderson TA Morries LD
author_facet	Henderson TA Morries LD
author_sort	Henderson TA
title	Near-infrared photonic energy penetration: can infrared phototherapy effectively reach the human brain?
title_short	Near-infrared photonic energy penetration: can infrared phototherapy effectively reach the human brain?
title_full	Near-infrared photonic energy penetration: can infrared phototherapy effectively reach the human brain?
title_fullStr	Near-infrared photonic energy penetration: can infrared phototherapy effectively reach the human brain?
title_full_unstemmed	Near-infrared photonic energy penetration: can infrared phototherapy effectively reach the human brain?
title_sort	near-infrared photonic energy penetration: can infrared phototherapy effectively reach the human brain?
publisher	Dove Medical Press
publishDate	2015
url	https://doaj.org/article/e63e208af69d46a8aef596110243c320
work_keys_str_mv	AT hendersonta nearinfraredphotonicenergypenetrationcaninfraredphototherapyeffectivelyreachthehumanbrain AT morriesld nearinfraredphotonicenergypenetrationcaninfraredphototherapyeffectivelyreachthehumanbrain
_version_	1718401704475492352

Near-infrared photonic energy penetration: can infrared phototherapy effectively reach the human brain?

Ejemplares similares