She effectiveness of laser therapy is undeniable - both in clinical practice, rehabilitation, physiotherapy, and in the light of science and research. It is commonly used in sports medicine and aesthetic medicine. What's behind the laser therapy phenomenon? What biological processes occur in the body under the influence of laser light? How is health improved, pain reduced and inflammation leveled? Why is this non-surgical form of treatment so effective?
How does laser therapy work?
On the action laser therapy Several thousand studies have been published. Many of them were carried out on cells in vitro, and the results obtained are sufficient to be sure that the laser light affects different types of cells in the human body. Among other things, they observed: an increase in angiogenesis (capillary formation), which is crucial in wound healing; elongation of axons in the nerve cell; stabilization of the cell membrane and many other changes at the cellular level.
Thus, laser therapy is primarily used to reduce pain and inflammation, as well as to promote tissue regeneration. It is commonly used in physiotherapy, rehabilitation and sports medicine. It is also increasingly used in aesthetic medicine and cosmetology, as studies show that laser therapy can improve skin texture and reduce fine lines and wrinkles. Undoubtedly, it is one of the more effective forms of non-surgical treatment Many injuries and ailments.
To understand, how laser therapy works, it is necessary to look at the photochemical effect that occurs in the target cell after absorption of laser light by the chromoform (the part of the cell that absorbs light). Examples of photochemical processes include photobiomodulation and photobiostimulation, during which photons, emitted by the laser, interact with target cells and cause specific biochemical changes (stimulating or inhibiting). The body's response to photon absorption can include: DNA and RNA synthesis, protein and collagen synthesis, and cell proliferation.
All of the above effects lead to faster regeneration of damaged tissues, which causes the laser light to effectively modulate cellular metabolism.
What does photobiostimulation consist of?
Although laser therapy works and its effectiveness cannot be denied, the very mechanism of action of photobiomodulation and photobiostimulation on the human body is not fully known and understood. There is a lively discussion on the subject in the scientific community. As a result, it is known that Not one, but several mechanisms are responsible for the health-promoting effects of laser therapy dependent on the type of cell being stimulated.
One of the proposed mechanisms of action of laser therapy is related to the fact that red light and infrared radiation emitted during laser therapy is absorbed by cytochrome C, which is located in the inner membrane of mitochondria. Cytochrome C is an important part of the respiratory chain (acts as a transporter), and in the example discussed here, it acts as a photoreceptor.
When cytochrome C absorbs light, it is automatically stimulated, and this leads to its greater activity. As a result, it binds more easily to oxygen, which makes it cytochrome C oxidase - a compound that is essential for the production of ATP.
It is the cell's energy carrier, which facilitates the course of biological reactions, is responsible for many mechanisms at the cellular level and is essential for life.
Stimulation of cytochrome C by laser therapy thus leads to faster cell proliferation, activation of intracellular metabolism, Reduce pain, reduce inflammation and accelerate tissue regeneration. Increases in growth factors (e.g. TGFb and bFGF) and inhibitors of metalloproteinases (e.g. TIMP) are also observed. As a consequence more collagen production occurs and at the same time its less degradation.
The importance of wavelength in laser therapy
Cells in the human body respond to light in a range of wavelengths: from ultraviolet to infrared. The color of the light, however, indicates the wavelength. Thus, in clinical practice, lasers used include ruby lasers (694 nm), argon lasers (488 nm and 514 nm), helium-neon lasers (623.8 nm), as well as lasers with wavelengths close to 1000 nm, since they penetrate tissue perfectly. It is also worth remembering that the color of the light emitted by the laser causes a particular type of tissue to absorb the energy sent out more. As a result, the key in laser therapy is to tailor the wavelength to the health problem in question.
For example, cytochrome C - due to its properties - absorbs light from 500 nm to 1100 nm. This is because tissue in the body can reflect, absorb, scatter or transmit light. Thus, in laser therapy, the key is to tailor the wavelength to the specific cell type. Laser therapy is effective and treats injuries because the light is able to penetrate individual tissues and reach the targeted cells.
Chromophores in biological tissue play an important role in laser therapy. These include melanin, water, hemoglobin and oxyhemoglobin.
The best results of laser therapy are achieved when a sufficient number of photons, expressed in joules (J), delivered to a given area (cm2).
Interestingly, it has been shown that tissues that are anemic (e.g., due to inflammation or damage) are more receptive to laser light than healthy tissues.
The absorption of laser light by the skin and subcutaneous tissue is greater the longer the wavelengths emitted. As a result, it is known that Waves up to about 1000 nm are effectively used for deeper penetration - relieve pain and inflammation, and accelerate tissue healing. Laser therapy tailors the spectrum of laser energy to a specific medical target.
High energy laser
High-energy laser radiation (HILT) is widely used in physiotherapy and sports medicine. This method allows the body's tissues to be treated without the risk of thermal damage.
Thanks to the use of high therapeutic power (up to 12 watts), a higher dose of energy reaches the tissues than during low-energy laser therapy.
In clinical practice, the most common use is lasers with a wavelength of about 1000 nm, as they have a unique ability to penetrate tissues. As a result, biostimulatory, anti-inflammatory and analgesic effects are possible, as well as regenerative effects. The use of a high power dose makes it possible to reach directly into the deeper tissues in the human body. Consequently, it is possible to achieve a rapid analgesic effect.
Low energy laser
Low-energy laser radiation (LLLT) is characterized by specific properties, including: monochromaticity, coherence and parallelism of the beam of rays. Low-energy laser therapy uses the effects of photobiostimulation and photobiomodulation. As a result, it is possible to induce desired phenomena at the cellular level (e.g., increased DNA and RNA synthesis, greater cell proliferation) and obtain observable clinical benefits (e.g., pain reduction, faster healing of dental implants).
The method of treatment with low-level laser radiation (LLLT) was introduced into clinical practice by Endre Mester, a Hungarian physician who is also a pioneer of laser medicine.
Low-energy laser radiation most often uses wavelengths of 500 to 1000 nm. In contrast, the human body is most strongly affected by wavelengths of 620-680 nm and 812-870 nm.
Laser therapy - the future of rehabilitation and medicine
Laser therapy is still a relatively young field of medicine with tremendous therapeutic potential. Although scientists have not yet learned all the relationships involved in laser therapy, It cannot be denied its high effectiveness in the non-surgical treatment of. Its use is also associated with proven therapeutic effects.
The technological advances made in recent years also translate into developments in the field of laser therapy.
Thus, it can be assumed that in the years to come, laser therapy will not only become more popular, but also even more effective, which will translate into greater treatment options in physiotherapy and rehabilitation.
Right now Laser therapies are widely used in sports medicine, where they relieve pain, reduce inflammation and speed up recovery to full health. Among their advantages are not only high effectiveness, but also non-invasive nature, which encourages many people to take advantage of related treatments.
Bibliography
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