Low intensity – high efficiency: the use of LILI in aesthetic medicine

Lyudmila Efimova, dermatocosmetologist, expert of the Interregional Professional Cosmetology Association, methodologist of the SportMedImport Group of Companies, (St. Petersburg).

About laser radiation in detail

Laser radiation is a type of physical energy not found in natural light sources. This radiation is produced by special devices - optical quantum generators ( OKGs ) of various designs, called lasers (from the English phrase Light Amplification by Stimulated Emission of Radiation - LASER ). Laser radiation and the principles of its production by lasers were simultaneously and independently discovered in the early 60s of the last century by Soviet and American physicists. And just a few years later (by the end of the same decade), the first attempts were made to use the radiation of low-intensity (therapeutic) lasers for therapeutic purposes.

Laser radiation is emitted by atoms of the working substance of the laser, which can be represented by a gas, liquid, crystal, or semiconductor.

One of the most important characteristics of laser radiation is the wavelength (measured in nanometers or micrometers). Depending on the wavelength, laser radiation can belong to different parts of the spectrum:

1. ultraviolet range (180–400 nm);
2. visible spectrum:

• violet (400–450 nm);
• blue (450–480 nm);
• blue (480–510 nm);
• green (510–575 nm);
• yellow (575–585 nm);
• orange (585–620 nm);
• red (620–760 nm).

3. infrared range:

• near region (760 nm – 15 µm);
• far region (15–30 µm).

In physiotherapy, laser radiation of the red and near-infrared ranges is most often used, which has the greatest penetrating effect and mild biological and therapeutic effects.

Depending on the output power, lasers are divided into:

• low-energy (radiation power density less than 0.4 W/cm2);
• medium-energy (radiation power density 0.4–10 W/cm2);
• high-energy (radiation power density more than 10 W/cm2).

In this article we will talk specifically about low-energy laser systems.

What are "NILI"?

To provide a biostimulating effect on the body (physiotherapy, physiotherapeutic cosmetology) , low-intensity laser radiation (LILI) is used. Medium to high intensity radiation is used to destroy or cut tissue in laser surgery.

When laser radiation interacts with the human body, part of the optical energy is reflected and scattered in space, and the other part is absorbed by biological tissues.

Under the influence of LILI, atoms and molecules of biological tissues pass into an excited state and participate more actively in physical and physicochemical interactions. Selective or preferential excitation of certain atoms or molecules is determined by the wavelength and frequency of LILI.

Absorption of LILI energy leads to a weakening of intramolecular and intermolecular interaction forces. This leads to the breakdown of tissue molecules, acceleration of intracellular biochemical reactions, and an increase in the content of free forms of biologically active molecules.

Thus, nonspecific stimulation of the biochemical activity of tissues exposed to laser irradiation occurs.

Operating principles of LILI

An important result of the effect of LILI on tissue is the enhancement of the specific activity of the cell’s nuclear apparatus: acceleration of DNA and RNA transcription, stimulation of protein synthesis on cell ribosomes. This ensures enhanced biosynthetic processes and, accordingly, a trophic-stimulating effect.

Under the influence of LILI, oxygen tension in tissues and its utilization by cells increases. There is a pronounced increase in local blood circulation, blood flow speed, an increase in the number of collaterals and functioning capillaries. An increase in the activity of oxygen metabolism contributes to the enhancement of energy and plastic processes in the cell.

The source of infrared LILI are semiconductor lasers. They are productive (efficiency - 40–60% versus 1–2% for helium-neon lasers) and provide deep penetration of radiation into biological tissues (up to 7 cm in the near-infrared wavelength range 0.8–1.2 μm).

Infrared laser radiation from semiconductor lasers can be continuous, continuous modulated or burst (pulsed).

The mildness of the physiological effect and the resulting greater therapeutic breadth, the distinct and long-lasting therapeutic effect and cosmetic effects are the main reasons for the increased interest that specialists show in near-infrared LILI. Semiconductor laser devices have undeniable operational advantages: portability, lightness, electrical safety, low power consumption.

Therapeutic effect of low-intensity laser radiation

LILI has a wide range of therapeutic effects, which are based on the mechanisms of physiological action of laser radiation discussed above.

• The anti-inflammatory effect is caused by the activation of the hormonal system that controls inflammatory reactions, as well as the improvement of local blood circulation, increased fibrinolysis, microcirculation and blood supply to tissues.
• The trophic-stimulating effect is caused by an increase in oxygen metabolism and ATP synthesis in the cell, as well as protein synthesis when exposed to LILI. Laser radiation stimulates trophic processes in tissue damage, degenerative processes, premature and age-related aging of tissues.
• The analgesic effect of LILI is not as intense as that of many other physical factors. However, it is stable and lasts for a long time. The action is associated with increased synthesis of endorphins and enkephalins - morphine-like endogenous mediators, as well as with a decrease in pain as a result of the elimination of tissue edema.
• The decrease in microbial contamination of infected wounds under the influence of LILI is explained by improved blood flow in the area of the pathological focus, increased chemotaxis of leukocytes to the area of inflammation and activation of proteolytic enzymes, which have a detrimental effect on microorganisms.
• The anti-edematous effect of LILI is due to the activation of local blood circulation, increased transport of substances through the vascular wall, which improves the conditions for drainage of interstitial tissue fluid into the vascular bed.
• Improvement of the body's immunity occurs due to the activation of phagocytosis, lysozyme activity and the desensitizing effect of laser radiation.

Summarizing the literature data and the results of our own research, we can highlight the following main types of therapeutic effects of LILI:

• stimulation of regeneration in tissues;
• anti-inflammatory;
• immunomodulatory;
• desensitizing;
• vasoactive;
• vegetotropic (sympatholytic, vagolytic);
• psychotropic (sedative, antidepressant);
• hematopoietic (erythropoietic, leukopoietic);
• hypocoagulant;
• analgesic.

All therapeutic and stimulating effects develop gradually and require a course of 5–15 procedures for the results to be stable. Indications and contraindications for low-level laser therapy are discussed in Table 1.

Table 1. Indications and contraindications for low-intensity laser therapy in dermatocosmetology

LILI in reflexology

Recent decades have been marked by the widespread introduction of low-intensity lasers into reflexology. The method of laser puncture (LP), the essence of which is the stimulation or relaxation of acupuncture points using the cutaneous method of low-intensity laser radiation, has become widespread.

The fundamental advantage of laser reflexology methods is the presence of a pronounced biostimulating effect at the cellular and tissue levels, which significantly increases the effectiveness of treating a wide range of diseases compared to traditional acupuncture. LP allows you to avoid complications associated with damage to the body and infection (AIDS, viral hepatitis, etc.). Non-invasiveness and painlessness of action expands the indications for use, in particular, in the elderly, debilitated patients, children, and people who are categorically afraid of injections. It is also significant to reduce the time spent on one procedure (up to 10–15 minutes), which greatly increases the doctor’s productivity.

To perform laser puncture, it is necessary that the device be equipped with a conical attachment to the emitter, which will focus the laser energy on a limited area (1–1.5 cm), which will allow adequate stimulation of the corporal or auricular point. The method of carrying out the procedure is by contact on pre-cleansed dry skin, with light pressure for more complete and deep penetration of radiation with minimal dispersion.

The laser puncture procedure can be carried out either as a single treatment or in combination with laser phoresis. For example, when working with a low-intensity diode infrared laser from the German company Vitalaser, an original protocol for the treatment of paraorbital hernias is used - first, drainage and lifting points of the middle third of the face are stimulated using laser puncture, and then laser phoresis of a gel with hyaluronic acid is performed on the skin of the upper and lower eyelids. The result is visible immediately after the first procedure, and the exposure time itself does not exceed 20 minutes. The same company is developing protocols for anti-stress laser puncture, effects to reduce the feeling of hunger in people on diet therapy, assistance in quitting smoking, relief of pain syndromes (including migraine and radicular pain), lowering blood pressure and many others.

Thus, using therapeutic and aesthetic laser puncture, a cosmetologist not only significantly expands the range of his patients, but also significantly increases his professional level and status.

The dynamic development of models of aesthetic low-intensity lasers, the constant expansion of the range of their applications, the simplicity and conciseness of procedures, the small number of contraindications and the high level of comfort of procedures indicate that these devices have a wonderful future in the hardware services market. So, is it really possible that a modern cosmetologist, having all this information, will still use this equipment only to administer hyaluronic acid and will not be interested in finding new protocols?

First published: Les Nouvelles Esthetiques Ukraine, No. 6 (70), 2011-2012