LASER EQUIPMENT FOR REJUVENATION

The first laser (LASER is an abbreviation of EnglishLight Amplificationby Stimulated Emissionof Radiation: amplification of light using induced (stimulated) radiation)for cosmetic purposes (in ruby) was designed and tested very recently, just 55 years ago, in 1960. Since then, laser cosmetology has been one of the most demanded fields in aesthetic medicine.

Laser devices are used with great success for hair removal, rejuvenation, facelift, removal of blood vessels, age spots, scars, stretch marks, post-acne, neoplasms, tattoos, for thetreatment of vitiligo, psoriasis, acne (acne), ingrown toenails.

Today's laser equipment review is highly specialized: we will familiarize readers in detail with skin rejuvenation devices.

LASER DEVICE

The laser consists of three main elements:

• energy source (or "pumping" mechanism);
• body of work (active environment);
Mirror system
• (optical resonator).

The source of energycan be an electric discharge, a flash lamp, an arc lamp, another laser, a chemical reaction, etc. , which activate the workplace with their energy.

The

Working fluidis ​​the main determining factor of the generated wavelength, as well as other properties of the laser (monochrome, coherence, narrow focus). There are hundreds, if not thousands, of different working bodies on the basis of which a laser can be built. However, the following working media are most often used: liquid (consists of an organic solvent, for example methanol, ethanol or ethylene glycol, in which chemical dyes are dissolved), gases (a mixture ofgases, for example: carbon dioxide, argon, krypton or mixtures such as neon lasers; these lasers are most often pumped by electric discharges), solids (such as crystals and glass; the solid material is usuallyactivated by adding small amounts of chromium, neodymium, erbium or titanium ions); semiconductors.

Thus, depending on the type of working environment (active environment), lasers are divided into:

gas
• ;
• liquid (on inorganic or organic dyes);
• metal vapor lasers;
• solid (crystals, glass);
• semiconductor (or diode).

The

optical resonator, the simplest form of which consists of two parallel mirrors, is located around the working body of the laser. Forced radiation from the workplace is reflected between mirrors and back into the workplace, accumulating energy. The wave can be reflected several times before going out. In more complex lasers, four or more mirrors are used, which also form an optical resonator, but of a more complex design.

The quality of manufacture and installation of these mirrors is one of the most important conditions for the quality of a laser system.

Also in the laser system, additional devices can be mounted to achieve various effects, such as rotating mirrors, modulators, filters and absorbers. Their use allows the parameters of laser radiation to be changed, for example, wavelength, pulse duration, etc.

TECHNICAL PARAMETERS OF LASER EQUIPMENT

Laser energy parameters:

1. Power, measured in watts (W).
2. Energy, measured in joules (J).
3. Energy density (J / cm2).
4. Pulse duration, measured in milli-, nano-, picoseconds.
5. Wavelength, measured in micrometers (μm) and nanometers (nm).

Laser radiation, acting on a living organism, is subject to the phenomena of reflection, absorption and diffusion. The degree of these processes depends on the condition of the skin: moisture, pigmentation, blood circulation, swelling of the skin and underlying tissues.

Many lasers target specific chromophores, which are biological structures that have a well-defined absorption spectrum. The ability of a chromophore to absorb light of different wavelengths with different intensities is determined by the absorption spectrum. The unit of measure for a chromophore's ability to absorb laser light is the absorption coefficient.

The absorption spectra of the different chromophores differ radically. Therefore, it is important that the wavelength of the laser radiation coincides with the wavelength at the peak of the absorption capacity of the chromophore to be exposed.

Therefore, there is not a universal wavelength, i. e. a laser, for all indications (appointments). Thus, a laser for hair removal cannot rejuvenate the skin, and vice versa. Of course, quite often it happens that several objectives are indicated in the instructions for the laser, but in fact there will be only one problem in effectively solving such equipment.

The depth of penetration of laser radiation is inversely proportional to the absorption coefficient and, therefore, depends on the wavelength. For different skin chromophores (water, melanin, hemoglobin, oxyhemoglobin), the depth of penetration is also different. For example, in the visible region (0. 38-0. 74 microns, or 380-740nm) the penetration depth will be 3-7mm, in the infrared region (0. 76-1. 5 microns) -from 0. 5 to 1. 5 mm, and in the ultraviolet region (0. 3-0. 5 microns), laser radiation is strongly absorbed by the epidermis and therefore penetrates into the tissues at a shallow depth, from 0, 2 to 0. 4 mm.

METHOD OF LASER RADIATION PRODUCTION

There arepulsed lasers and cwgenerating radiation. Depending on the pumping method, a continuous and pulsed generation of laser radiation can be achieved. Pulsed light is generated as wave beams interrupted for a specified period of time. Other lasers generate continuous light and a special device divides this light into short segments. Typically, continuously generated radiation lasers, in addition to physiotherapy lasers, have the property of releasing unwanted heat at the site of exposure, which can lead to scar changes and damage to the tissues surrounding the body. exhibition site.

LASER POWER LEVEL

The radiation power of medical lasers (in particular cosmetic lasers) varies within wide limits, determined by the purposes of their application. For continuously pumped lasers, the power can vary from 0. 01 to 100 W. Pulsed lasers are characterized by pulse power and pulse width. The power of pulsed lasers is several orders of magnitude higher. Thus, a neodymium laser generates a pulse with an energy of E = 75 J, the duration of which is t = 3x10-12 s. Pulse power: P = E / t = 2. 5x1013 W (for comparison: the power of the hydroelectric power station is about 109 W).

In the practice of cosmetology, including for skin rejuvenation procedures, laser radiation is used both with a low-power (low-intensity laser radiation, LLLT) and high (high-intensity laser radiation) value. high intensity, LILI).

LOW INTENSITY LASER RADIATION (LLLT)

The action of LLLT is to activate enzymes in cell membranes and stabilize lipids. LLLT is known to stimulate cell division and development. The effect occurs at a subtle, atomic-molecular level, where energy is absorbed under the influence of laser radiation of a certain frequency (as a rule, in the red and infrared ranges). Such energy absorption leads to a sharp increase in the intracellular concentration of Ca2 +, that is, there is an activation of the accumulation and release of ATP, the restoration of cell membranes, an increase in intracellular metabolism and an increase in regenerative processes due to the activation of cell proliferation (division). Old cells are intensively replaced with new ones, and the biorhythm of this process is restored. The therapy uses low intensity lasers (with an intensity of 0. 1 to 10 W / cm2). The maximum wavelength for therapeutic lasers is 1300 nm. In particular, diode lasers are used for skin rejuvenation procedures:

• transmitters with wavelengths of 890 nm and 915 nm (laser rejuvenation);
• low intensity laser with a wavelength of 785 to 890 nm (laser biorevitalization and laser mesotherapy - delivery of active ingredients to the skin by LLLT).

Treatments with therapeutic lasers are painless and comfortable for the patient due to their low intensity. In some cases, you may feel a slight heat. There is no rehabilitation period, however, in order to achieve a pronounced effect (improvement of elasticity and firmness of the skin, microrelief, hydration and skin lifting), a series of procedures andsupport procedures is required.

The basic set of therapeutic lasers consists of a combined device with a control panel (sometimes in the form of a touch screen) and a handpiece transmitter. The kit may include several transmitters (for example, with a large work surface for working on the body and with a small area for working on the face), as well as accessories for various procedures. Therapeutic lasers have small dimensions, low power consumption and the ability to install the working environment directly into the handpiece, without using a light guide tool to deliver the radiation.

HIGH INTENSITY LASER RADIATION (WHEEL)

High intensity laser radiation (2500 J / cm2) allows to concentrate a large amount of energy in a small volume, which causes local thermal heating, rapid evaporation and hydrodynamic explosion in a biological environment. In cosmetology, VILI is widely used, one of which is skin rejuvenation.

Skin rejuvenation using high intensity laser radiation is a modern method of lifting, removing and / or reducing the depth of wrinkles and improving the quality of the skin. For high-intensity laser rejuvenation, these devices are used whose radiation is well absorbed by water (since the skin is 77% water). The aim of using such lasers is a rapid rise in temperature in the absorption region of a laser pulse with instantaneous evaporation of the tissue.

Among the variety of high-intensity laser equipment for skin rejuvenation, specialists usually distinguish two main types of devices: fornon-ablativeandablative method.

Ablation - evaporation of superficial tissue by means of laser exposure.

Laser ablation devicesare extremely effective in combating age-related skin changes: the breakdown of collagen and elastin - structural proteins in the skin that give it firmnessand elasticity. Traumatic laser treatments are applied to trigger the renewal processes. In addition, it should be noted that the stronger the injury, the more powerful the rejuvenating effect, but at the same time, of course, the longer the rehabilitation period, the greater the risk of side effects.

This is why the main trends in the development of modern lasers for skin rejuvenation are the search for a compromise, an attempt to find a way to minimize trauma to the skin, but at the same time achieve apowerful response to a regenerative response.

Modern ablative devices include:

• fractionated CO2 lasers (carbon dioxide lasers);
• YAG (yttrium-aluminum-garnet solid crystal laser with erbium ions) erbium fractional lasers.

It is necessary to clarify the term "factional" right away.

A fractional laser differs from a conventional laser in that the laser beam is forcibly divided into a multitude of micro-beams ("fractions"). This can be implemented in hardware in several ways:

1. using microlenses installed in the handpiece (a large number of beams simultaneously strike the skin);
2. in scanner mode, when a laser beam sequentially perforates the skin;
3. with a roller attachment, which is controlled by laser pulses and allows the procedure to be performed in motion.

This leads to the fact that the laser effect on a particular area of ​​the skin does not become total, but zonal: not the entire surface of the skin is exposed to the effect, but thousands of its micro-areas, between which remains unaffected tissue. Fractional lasers are less traumatic: at the time of tissue treatment, they do not cover the entire surface of the skin, but 3 to 70%, depending on the laser settings, while triggering the recovery mechanism over the entire area.

Indeed, thanks to the advent of fractional lasers, a new era of laser cosmetology has begun: laser procedures have become less painful, safer ("delicate"), the period of rehabilitation after procedures has been considerablyreduced (from two days to one week). At the same time, the clinical effectiveness did not decrease, but, on the contrary, increased.

modern carbon dioxide lasersoperate on the principle offractional photothermolysis, which consists of the formation of microzones of coagulation in the form of columns perpendicular to the surfaceskin. The term "photothermolysis" here means the destruction of tissues under the influence of temperature, which occurred during the transfer of energy from laser radiation to the tissues (photo - light, thermal - heating, lysis - destruction). The carbon dioxide laser has a radiation wavelength of 10. 6 microns. When performing the fractional rejuvenation procedure, this laser removes microzones from the skin virtually to the full depth of the epidermis (down to 20 microns), while the area of ​​thermal damage extends into the dermis from150 microns or more, causing collagen to clot. This leads to the desired effect (reduction of denatured collagen fibers, smoothing of the skin).

There are currently a number of fractional carbon dioxide devices on the market with adjustable flux density and pulse duration. This allows you to choose the temperature and depth of heating of the dermis. Thanks to new technologies, the time to complete post-procedural recovery has been reduced to one week. Companies - distributors of modern carbon dioxide lasers began to advertise the procedures carried out with their help as "weekend" rejuvenation procedures, because during fractional laser photothermolysis, the period of "acute" rehabilitation (intense edema and erythema) proceeds on two days off, and on Monday the patient can go to work.

The Erbium laser has a wavelength of 2. 94 microns and a much higher water absorption coefficient than a carbon dioxide laser. Erbium laser radiation penetrates to a depth of approximately 1 micron, causing rapid vaporization of a thin layer of the epidermis with virtually no damage to surrounding tissue.

“The Erbium laser (Er: YAG) is a typical ablative laser. The ablation effect is so pronounced that the top layer of the epidermis instantly evaporates without leaving a trace. This laser is well suited for resurfacing, smoothing scars, removing pigmentation. "

Today, erbium lasers are actively used to work on the most sensitive areas: the neck and décolleté, the paraorbital and periorbital areas. With this laser, each point can be treated multiple times, while the doctor has the ability to control the entire "grinding" process. It is erbium lasers that are actively used intraoperatively by plastic surgeons. Additionally, erbium lasers are preferred when the patient is not ready for long term rehabilitation.

high intensity non-ablative lasersdo not work on the principle of evaporation, but on the principle of heating water and coagulation with the formation of new collagen in the areasaffected.

To implement the non-ablative method, as a rule, a laser with a large depth of penetration into the tissue is chosen. In this category, for rejuvenation, theneodymium (Nd: YAG)(neodymium-doped yttrium-aluminum-garnet crystal) laser with a wavelength of 1064 nm, which corresponds to the spectrum ofnear infrared, is mainly used.

Radiation from such a laser can penetrate the dermis to a depth of 5mm. With the aim of rejuvenating the skin, this laser is typically used in the millisecond and nanosecond pulse range, which helps stimulate collagen synthesis (in almost all cases) without damaging surrounding tissue, i. e. 'that is to say in non-ablative mode. But when focusing in a small place, it can also be used for ablation.

In modern cosmetology, neodymium laser is mainly used to remove unwanted vessels, such as spider veins, but also for photorejuvenation. The technique even has a separate name -non-ablative skin reshaping. In this case, the object of influence is hemoglobin. The purpose of the action is to stimulate the growth of collagen. Heat is generated where laser radiation is absorbed most, such as the upper papillary layer, and travels to nearby tissues. The consequence is a predictable inflammatory response causing changes in the skin synthesis of collagen with a concomitant effect of skin renewal. Thus, due to the partial coagulation of the microvascular bed and the partial denaturation of the collagen structure, the laser triggers the formation of young fibroblasts.

I would particularly like to highlight the latest developments in the field of laser technologies for skin rejuvenation - the emergence of picosecond lasers.

“In 2015, the central theme of all major international laser medicine conferences was the use of picosecond lasers for rejuvenation. This is a completely new and promising technology that only appeared in 2014 and received FDA approval. The principle of operation of picosecond lasers goes beyond the theory of selective photothermolysis, because they do not affect the tissue by heating (thermolysis), but by instantaneous supersaturation of the target with energy ”.

The picosecond laser generates pulses whose duration is measured in trillionths of a second. Such short pulses do not have time to inflict thermal damage to tissues, but so much energy is concentrated there that their target instantly decays into microparticles, forming vacuoles. This principle of exposure is called photomechanical exposure. In response to the formation of vacuoles in the skin layer, a reaction begins which triggers the synthesis of new collagen.

The world's leading experts in laser medicine, providing independent reports on fractional picosecond technologies, claim that these lasers provide an effect comparable to traditional ablative fractional lasers, absolutely painless to the patient. But the most important argument in favor of this technology for a modern metropolitan resident is the ultra-short rehabilitation, which takes three to twenty-four hours. It should also be noted that it is not necessary to spend time on anesthesia before the procedure, and the process itself, due to the very high pulse repetition frequency, does not take more than thirtyminutes. "

Lasers for skin rejuvenation can be divided into profile lasers and complex multifunctional laser systems ("combine").Each type of equipment has its advantages and disadvantages, its fans and its opponents. Many cosmetologists see more benefits in the so-called laser harvester.

“The modular platform allows the beautician to gradually expand the capabilities of the beautician by purchasing other accessories. Each nozzle has its own type of emitter, and buying a nozzle is always cheaper than buying a separate device. It should be remembered that such modular systems allow the doctor to have all types of lasers to solve specific problems, and not to use a single laser for both hair removal and rejuvenation, because the principle of selectionimplies that each wavelength will do a good thing, and all other indications are secondary. Therefore, modular devices with accessories have been designed so that the clinic does not buy 5-6 separate devices, but has a modular platform with different laser accessories, which is always cheaper in terms of money. and more rational in terms of patient loading than six separate lasers, each of which takes up space and is loaded with patients at best two or three days a week. "

Some people think that the multifunctional device is not suitable for large clinics where doctors work “on the fly”.

"Multifunctional machines have a significant disadvantage: failure of such a combine will cause failure of all functions at once, and a combine is not always a good choice for asituation where there are several cabin specialists "on duty" in different offices. "

In all cases, the choice is up to the buyer and depends on many factors: the size of the company, the profile, the number and specialization of doctors, the financing, in the end.

“The debate on the advantages and disadvantages of the two versions is like discussing the advantages of a smartphone with a camera compared to a digital SLR. If you want to take photos, call and surf the Internet at the same time, the choice is obvious. But if you are a professional photographer, the possibilities of the phone's camera will hardly be enough for you. "

To make the right choice of laser rejuvenation machine, experts recommend focusing on the following very important aspects:

1. It is necessary to request the results of clinical trials of this model from distributors.
2. You should talk to specialists at different salons and clinics working on the equipment you are interested in, check out their comments.
3. As a rule, serious companies offer customers the opportunity to test the device by specialists in the salon, so that employees and administration can assess the effectiveness and benefits of the equipment offered.
4. All laser devices must have a registration certificate from the Ministry of Health and a Gosstandart declaration of conformity.
5. You have to pay attention that the term of use of the maniples in some models is limited, it involves additional costs. Therefore, you should ask the supplier to provide a document confirming the guaranteed number of pulses, and not be guided by the words of the manager who sells the device.
6. Be sure to check with the distributor what the device consumables are (in addition to the manual ones), how often they should be purchased, how much they cost and if they are still in stock.
7. Find out how the post-warranty maintenance of the device will work, under what conditions and under what conditions.
8. Find out who and how is training specialists to work on this device, how many specialists can be trained to purchase, under what conditions, if the training will be repeated, if the specialist staff in your salon changes and under what conditions.

In conclusion, we would like to remind you that the use of laser techniques for rejuvenation requires that beauty salons and clinics have a medical license and specialists who have the right to provide services using equipment forthis class - physicians who have undergone special training under the "Standard Additional Professional Education Program for Physicians in Laser Medicine".