Laser therapy is a specific form of light-based therapeutic intervention that utilizes controlled applications of low-intensity, coherent and monochromatic light (i.e., LASER) in humans and animals to produce clinically-beneficial outcomes.
Laser therapy is a painless, non-invasive and very safe treatment that uses controlled amounts of laser light to modulate natural biological processes to produce beneficial clinical effects, such as:
⦁ Relieving pain;
⦁ Resolving chronic and acute inflammation;
⦁ Reducing oedema;
⦁ Healing and regenerating neural tissues;
⦁ Promoting wound healing and tissue repair; and,
⦁ Modulating immune response.
Laser Therapy is not a thermal modality; in most applications, local tissue temperature will not rise more than 1-2°C. At its primary level, laser therapy depends upon the actual interaction between light and tissue, such as the absorption of photons by photoreceptive molecules (chromophores) at a sub-cellular level. These primary interactions create photochemical and photophysical reactions that lead to a cascade of biological processes.
By controlling for photon energy (wavelength), and the rate (power), quantity (time) and distribution (intensity) of that energy as it is delivered to the tissue, we can influence various photochemical and photophysical processes and the biological activities they support, thereby tailoring effects to produce desired clinical outcomes.
How does Laser Therapy Work?
The effects of all light and laser therapies are primarily photochemical; not thermal - at least, not on a macro-scale – and result from a chain of mechanisms initiated by photon absorption:
Primary: Absorption of photons by photo-receptive molecules (chromophores such as e.g. cytochromes, porphyrins, etc.) and the transduction of photon energy to induce chemical changes (i.e., photochemistry)
Secondary: Modulation of ATP production (dose dependent), Nitric Oxide release, and the formation of Reactive Oxygen Species (ROS);
Tertiary: The products of secondary mechanisms then produce effects such as gene transcription, inter-cellular signaling, and vasodilation; and,
Quaternary: Vasodilation increases perfusion, facilitating improved oxygenation and recruitment of macrophages, neutrophils and lymphocytes to areas undergoing repair and/or infection as well as further re-vascularization and proliferation of cells to aid healing. Improved perfusion will also facilitate clearance of inflammatory cells, fluids and debris (i.e. lymphatic drainage) more efficiently
