How does laser therapy work?

How does laser therapy work?

The effects of laser therapy are photochemical in general and with super-pulsed lasers such as the Lumix 2 also photomechanical. Photons enter the tissue and are absorbed in the cell’s mitochondria and at the cell membrane by chromophores. These chromophores are photosensitizers that generate reactive oxygen species following irradiation thereby influencing cellular redox states and the mitochondrial respiratory chain. Within the mitochondria, the photonic energy is converted to electromagnetic energy in the form of molecular bonds in ATP. It is obvious that, in order to interact with the living cell, laser light has to be absorbed by intracellular chromophores.

Cell membrane permeability increases, which promotes physiological changes to occur. These physiological changes affect macrophages, fibroblasts, endothelial cells, mast cells, bradykinin, and nerve conduction rates.

The clinical and physiological effects are obtained by the way in which the tissues absorb laser radiation. This tissue absorption depends on the wavelength of the beam itself and the power to ensure that the laser energy reaches the target tissue at the necessary clinical levels. The use of an improper wavelength laser would not penetrate into the tissue to reach the target area. Furthermore, even if one has a laser with the proper wavelength, if the device does not have enough power to drive the energy into the tissue, the target area may not realize the potential benefits.

Each type of laser emits light at a very specific wavelength which interacts with the irradiated tissue. It also acts in particular with the chromophores present in the tissue, but in a different way. A chromophore, intrinsic or extrinsic, is any substance, colored or clear, which is able to absorb radiation. Among the endogenous chromophores, water and hemoglobin, nucleic acid and proteins can be listed. Among the exogenic chromophores we can instead find porphyrins and hematoporphyrins, which are injected into the organism. These are described as photosensitizers because they fix themselves to the tissue making it photosensitive at specific wavelengths.