Red & Near Infrared Light
Laser therapy involves the applying red and near infra-red light over injuries in order to encourage healing and to relive pain without drugs and side effects.
It is commonly used for treating injuries in performance animals such as racehorse and greyhound, but can also be used to treat other animals, safely and effectively. Laser Light at various wavelengths encourage healing and rejuvenate cells, whilst reducing inflammation and helping blood flow towards damaged tissue.
Scientists in the US along with NASA came up with the term Photobiomodulation.
The following factors impact upon the effectiveness of laser therapy:
- Wavelength (colour of the light)
- Intensity
- Energy delivered
The type of light used (red or near infra-red) that is, the wavelength used, the intensity in terms of output power, as well as the total energy in Joules/cm2 delivered to the injured muscle group.
The correct dosage delivered impacts upon the effectiveness of the laser therapy and how it impacts upon the quality and rate of pain relief, wound healing, inflammation and regenerating nerves.
Properties of Light
Sunlight
Many different colors
LASER (Light Amplification by the Stimulation of Emitted Radiation)
One color (monochromatic) and waves in phase (coherent)
LED (Light Emitting Diode)
One color (monochromatic) and waves not in phase (non-coherent)
NASA research further explains:
“Low-energy photon irradiation by light in the far-red to near-IR spectral range with low-energy (LLLT) lasers or LED arrays has been found to modulate various biological processes in cell culture and animal models. This phenomenon of photobiomodulation has been applied clinically in the treatment of soft tissue injuries and the acceleration of wound healing. The mechanism of photobiomodulation by red to near-IR light at the cellular level has been ascribed to the activation of mitochondrial respiratory chain components, resulting in initiation of a signaling cascade that promotes cellular proliferation and cytoprotection.”
“A growing body of evidence suggests that cytochrome oxidase is a key photoacceptor of light in the far-red to near-IR spectral range. Cytochrome oxidase is an integral membrane protein that contains four redox active metal centers and has a strong absorbency in the far-red to near-IR spectral range detectable in vivo by near-IR spectroscopy.”
“Moreover, 660–680 nm of irradiation has been shown to increase electron transfer in purified cytochrome oxidase, increase mitochondrial respiration and ATP synthesis in isolated mitochondria, and up-regulate cytochrome oxidase activity in cultured neuronal cells.”
“LED photostimulation induces a cascade of signaling events initiated by the initial absorption of light by cytochrome oxidase. These signaling events may include the activation of immediate early genes, transcription factors, cytochrome oxidase subunit gene expression, and a host of other enzymes and pathways related to increased oxidative metabolism.”
“In addition to increased oxidative metabolism, red to near-IR light stimulation of mitochondrial electron transfer is known to increase the generation of reactive oxygen species. These mitochondrially generated reactive oxygen species may function as signaling molecules to provide communication between mitochondria and the cysts and nucleus.”
Therapeutic photobiomodulation for methanol-induced retinal toxicity.
Proc Natl Acad Sci U S A. 2003 Mar18; 100(6): 3439-44. Epub 2003 Mar 07
