Introduction of Photobiomodulation Helmet
Photobiomodulation (PBM) describes the use of red or near-infrared light to stimulate, heal, regenerate, and protect tissue that has either been injured, is degenerating, or else is at risk of dying. One of the organ systems of the human body that is most necessary to life, and whose optimum functioning is most worried about by humankind in general, is the brain.
The brain suffers from many different disorders that can be classified into three broad groupings: traumatic events (stroke, traumatic brain injury, and global ischemia), degenerative diseases (dementia, Alzheimer’s and Parkinson’s), and psychiatric disorders (depression, anxiety, post traumatic stress disorder). There is some evidence that all these seemingly diverse conditions can be beneficially affected by applying light to the head. There is even the possibility that PBM could be used for cognitive enhancement in normal healthy people.
In this transcranial PBM (tPBM) application, near-infrared (NIR) light is often applied to the forehead because of the better penetration (no hair, longer wavelength).
PBM therapy was developed more than 50 years ago; however, there is still no common agreement on the parameters and protocols for its clinical application. Some research teams have recommended the use of a power density of less than 100 mW/cm2 and an energy density of 4 to 10 J/cm2 . Others groups recommend as much as 50 J/cm2 at the tissue surface . Parameters like wavelength, energy,
fluency, power, irradiance, pulse mode, treatment duration, and repetition rate can be applied in a wide range.
Our present preliminary results showed a clear response of cerebral rSO2 in relation to the LED stimulation. However, it has to be mentioned that the temperature increased significantly, and these effects have to be taken into account in further studies in detail. There is also the fact that ineffective studies in cells with high mitochondrial activity appear to be due more often to over-dosing than to under-dosing . Therefore, clinical studies concerning the optimal stimulation doses are necessary.