LASER REJUVENATION EQUIPMENT

The first laser (LASER is an abbreviation of EnglishLight amplification by stimulated emission of radiation: light amplification by induced (stimulated) radiationfor cosmetic purposes (in rubies) was designed and tested very recently, only 55 years ago, 1960. Since then, laser cosmetology has been one of the most sought after areas in aesthetic medicine.

Laser devices are used with great success for epilation, rejuvenation, lifting, removal of blood vessels, age spots, scars, stretch marks, post-acne, neoplasms, tattoos, for the treatment of vitiligo, psoriasis, acne (acne), nail ingrown.

Today's review of laser equipment is highly specialized: we will introduce readers in detail to skin rejuvenation devices.

LASER DEVICE

The laser consists of three main elements:

• energy source (or "pumping" mechanism);
• working body (active environment);
• mirror system (optical resonator).

Energy sourcecan be electric discharge, flash, arc lamp, other laser, chemical reaction, etc. , which activate the working medium with their energy.

Working fluidis ​​the main deciding factor of the generated wavelength, as well as other properties of the laser (monochrome, coherence, narrow focus). There are hundreds or even thousands of different working bodies on the basis of which a laser can be built. However, the following working media are most commonly used: liquid (consisting of an organic solvent, for example methanol, ethanol or ethylene glycol, in which chemical dyes are dissolved), gases (mixture of gases, for example: carbon dioxide, argon, krypton or mixturessuch as helian ion lasers; these lasers are usually pumped by electric discharge), solids (such as crystals and glass; solids are usually activated by the addition of small amounts of chromium, neodymium, erbium or titanium ions); semiconductors.

So, according to the type of working medium (active medium), lasers are divided into:

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

Optical resonator, whose simplest shape is two parallel mirrors, is located around the working body of the laser. Forced radiation of the working fluid is reflected between the mirrors and back into the working fluid, accumulating energy. The wave can be reflected many times before it comes out. More complex lasers use four or more mirrors that also form an optical resonator, but of a more complex design.

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

Additional devices can also be placed in the laser system to achieve various effects, such as rotating mirrors, modulators, filters and absorbers. Their use allows you to change the parameters of laser radiation, for example, wavelength, pulse duration, etc.

TECHNICAL PARAMETERS OF LASER EQUIPMENT

Laser power 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 that acts on a living organism is subject to the phenomena of reflection, absorption, scattering. 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 with a well-defined absorption spectrum. The ability of a particular chromophore to absorb light of different wavelengths of different intensities is determined by the absorption spectrum. The unit of measurement for the ability of a chromophore to absorb laser light is the absorption coefficient.

The absorption spectrum of different chromophores is radically different. 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.

So, there is no one universal wavelength, or one laser, for all indications (tasks). Thus, a laser hair removal cannot rejuvenate the skin, and vice versa. Of course, it often happens that several purposes are indicated in the laser instructions, but in fact there will be only one problem that effectively solves such equipment.

The depth of penetration of laser radiation is inversely proportional to the absorption coefficient and as a consequence 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 380-740 nm) penetration depth will be 3-7 mm, 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) the epidermis strongly absorbs laser radiation and therefore penetrates the tissues to a shallow depth, from 0, 2 to 0, 4 mm.

LASER RADIATION GENERATION METHOD

There arepulsed and cw lasersthat generate radiation. Depending on the pumping method, continuous and pulsed generation of laser radiation can be obtained. Pulsed light is created as beams of waves that are interrupted for a certain time. Other lasers generate continuous light, and a special device divides that light into short segments. As a rule, continuous radiation lasers, in addition to physiotherapy lasers, have the property of unwanted heat release at the site of exposure, which can lead to changes in scars and tissue damage surrounding the site of exposure.

LASER POWER LEVEL

The radiation power of medical (especially cosmetic) lasers varies widely, with a specific purpose. For lasers with continuous pumping, the power can vary from 0. 01 to 100 W. Pulsed lasers are characterized by pulsed power and pulse duration. The power of pulsed lasers is several orders of magnitude higher. Thus, the neodymium laser generates a pulse with energy E = 75 J, whose duration is t = 3x10-12 s. Pulse power: P = E / t = 2, 5x1013 W (for comparison: the power of the hydropower plant is approximately 109 W).

In cosmetology practice, including skin rejuvenation procedures, laser radiation is used with both low power value (low intensity laser radiation, LILI) and high (high intensity laser radiation, VILI).

LOW INTENSITY LASER RADIATION (LLLT)

The action of LLLT is to activate cell membrane enzymes and stabilize lipids. LLLT is known to stimulate cell division and development. The effect occurs at the subtle, atomic-molecular level, where energy is absorbed under the influence of laser radiation of a certain frequency (usually in the red and infrared range). Such energy absorption leads to a sharp increase in intracellular Ca2 + concentration, ie activation of ATP accumulation and release, renewal of cell membranes, increase of intracellular metabolism and increase of regenerative processes due to 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. 1-10 W / cm2). The maximum wavelength for therapeutic lasers is 1300 nm. Diode lasers are especially used for skin rejuvenation:

• emitters of 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 using LLLT).

Therapeutic laser treatments are painless and comfortable for the patient due to their low intensity. In some cases, you may feel a slight warmth. There is no rehabilitation period, however, in order to achieve any pronounced effect (improvement of skin elasticity and firmness, microrelief, moisturizing and lifting of the skin), a course of procedures and accompanying procedures is required.

The basic set of therapeutic lasers includes a device combined with a control panel (sometimes in the form of a touch screen) and a handheld emitter. The kit can contain several emitters (for example, with a large work surface for working on the body and with a small work surface for working on the face), as well as extensions for various procedures. Therapeutic lasers have small dimensions, low energy consumption and the possibility of installing the working medium directly in the soldering iron, without the use of a light guide to deliver radiation.

HIGH INTENSITY LASER RADIATION (DOK)

High intensity laser radiation (2500 J / cm2) enables the concentration of significant energy in a small amount, which causes local thermal heating, rapid evaporation and hydrodynamic explosion in the biological environment. In cosmetology, VILI has the widest application, one of which is skin rejuvenation.

High-intensity laser rejuvenation of the skin is a modern method of lifting, removing and / or reducing the depth of wrinkles and improving skin quality. For high-intensity laser rejuvenation, those devices are used whose radiation is well absorbed by water (because the skin is 77 percent water). The purpose of using such lasers is a rapid rise in temperature in the area of ​​laser pulse absorption with instantaneous tissue evaporation.

Among the various high-intensity laser devices for skin rejuvenation, it is common for experts to distinguish between two main types of devices: fornon-ablativeandablative methods.

Ablation - evaporation of surface tissues by laser exposure.

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

Therefore, 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 skin trauma, but at the same time get a strong response to the regenerative response.

Modern ablative devices include:

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

The term "fractional" needs to be clarified immediately.

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

1. with the help of microlenses installed in the soldering iron (a large number of rays hit the skin at the same time);
2. in scanner mode, when one laser beam sequentially perforates the skin;
3. with a cylindrical extension, which is controlled by laser pulses and allows the procedure to be carried out in motion.

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

In fact, thanks to the advent of fractional lasers, a new era of laser cosmetology has begun: laser procedures have become less painful, safer ("more sensitive"), the rehabilitation period after the procedure has been significantly reduced (from two days to one week). At the same time, clinical efficiency did not decrease, but, on the contrary, increased.

Modern carbon dioxide lasersoperate on the principlefractional photothermolysis, which consists in creating coagulation microzones in the form of pillars perpendicular to the skin surface. The term "photothermolysis" here means the destruction of tissue under the influence of temperature generated in the process of transferring laser energy to the tissue (photo - light, thermal - heating, lysis - destruction). The carbon dioxide laser has a radiation wavelength of 10. 6 microns. During the fractional rejuvenation procedure, this laser removes skin microzones at practically the entire depth of the epidermis (up to 20 microns), while the zone of thermal damage extends into the dermis by 150 microns or more, which causes collagen coagulation. This leads to the desired effect (reduction of denatured collagen fibers, smoothing of the skin).

There are a number of fractional carbon dioxide devices on the market today with adjustable flow density and pulse duration. This allows you to select the temperature and depth of heating of the dermis. Thanks to new technologies, the time for complete post-procedural recovery has been reduced to one week. Companies - distributors of modern carbon dioxide lasers have started to advertise the procedures performed with their help as procedures for rejuvenating the "weekend", because when performing fractional laser photothermolysis, the "acute" rehabilitation period (intense edema and erythema) passes in two days off. Monday the patient can go to work.

The erbium laser has a wavelength of 2. 94 microns and a much higher absorption coefficient than a carbon dioxide laser. Erbium laser radiation penetrates to a depth of about 1 micron, causing rapid evaporation of a thin layer of the epidermis without nearly damaging the surrounding tissues.

“Erbium laser (Er: YAG) is a typical ablative laser. The effect of ablation is so pronounced that the upper layer of the epidermis instantly evaporates without leaving any traces. This laser is very suitable for restoring surfaces, smoothing scars and removing pigmentation. "

Today, erbium lasers are actively used in working with the most sensitive areas: neck and décolleté, paraorbital and periorbital areas. With this laser, each point can be processed several times, while the doctor has the ability to control the entire process of "grinding". Plastic surgeons actively use erbium lasers intraoperatively. Also, erbium lasers are more desirable 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 coagulating with the formation of new collagen in the affected areas.

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

The radiation of such a laser can penetrate the dermis to a depth of 5 mm. For the purpose of skin rejuvenation, this laser is usually used in millisecond and nanosecond pulse ranges, which enables the stimulation of collagen synthesis (in almost all cases) without damaging the surrounding tissues, ie in a non-ablative manner. But when you focus on a small place, it can also be used for ablation.

In modern cosmetology, the neodymium laser is primarily used to remove unwanted veins, such as spider veins, but also for photorejuvenation. The technique even has a separate name -non-ablative skin remodeling. In this case, the subject of influence is hemoglobin. The purpose of the action is to stimulate the growth of collagen. Heat is generated where laser radiation is most absorbed, such as the upper papillary layer, and spreads to nearby tissues. The result is a predictable inflammatory response that causes changes in dermal collagen synthesis with a concomitant skin rejuvenation effect. Thus, due to the partial coagulation of the microvascular layer and the partial denaturation of the collagen structure, the laser initiates the formation of young fibroblasts.

I would especially like to mention the latest achievements in the field of laser technologies for skin rejuvenation - the appearance of picosecond lasers.

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

The picosecond laser generates pulses, the duration of which is measured in billions of seconds. Such short pulses do not have time to cause heat damage to the tissues, but so much energy is concentrated in them that their target instantly decomposes into microparticles, creating vacuoles. This principle of exposure is called photomechanical exposure. In response to the formation of vacuoles in the dermal layer, a reaction begins that triggers the synthesis of new collagen.

The world’s leading laser medicine experts, providing independent reports on fractional picosecond, claim that these lasers provide an effect comparable to traditional ablative fractional lasers, absolutely painless for the patient. But the most important argument in favor of this technology for the modern inhabitants of the metropolis is the ultra-short rehabilitation that lasts from three to twenty-four hours. It should also be noted that before the procedure it is not necessary to spend time on anesthesia, and the procedure itself, due to the very high rate of pulse repetition, lasts no more than thirty minutes. "

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

“The modular platform allows you to gradually expand the possibilities of beauticians by purchasing other supplements. Each nozzle has its own type of emitter and it is always cheaper to buy a nozzle than to buy a separate device. It should be borne in mind that such modular systems allow the physician to have all types of lasers to solve certain problems, rather than using one laser for both hair removal and rejuvenation, because the selective principle implies that each wavelength will do one. well, and all other indications are secondary. Therefore, modular devices with extensions were made so that the clinic did not buy 5-6 separate devices, but had one modular platform with different laser extensions, which is always cheaper and more rational in terms of patient load of six separate lasers, each of which takesspace and is burdened on patients at best two or three days a week. "

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

"Multi-purpose machines have one important drawback: the failure of such a combine will mean the breakdown of all functions at once, and the combine is not always a good choice for a situation where there are several experts" in progress "in different offices. "

In any case, the choice depends on the customer and ultimately depends on many factors: the size of the company, the profile, the number and specialization of the doctor, the financing.

“Discussing the advantages and disadvantages of both versions is like discussing the advantages of a smartphone with a camera over a DSLR. 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 camera capabilities of this phone will hardly be enough for you. "

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

1. The results of clinical trials of this model should be requested from the distributor.
2. You should talk to experts from different salons and clinics working on the equipment you are interested in and find out their feedback.
3. As a rule, serious companies provide customers with the opportunity to test the device by salon specialists, so that employees and administration will be able to assess the efficiency and benefits of the equipment offered.
4. All laser devices must have a certificate of registration from the Ministry of Health and a Gosstandart declaration of conformity.
5. It should be noted that the shelf life of the distributor in some models is limited, this implies additional costs. Therefore, you should ask the supplier to submit 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 which consumables the device has (in addition to the manipulator), how often they will have to be purchased, how much it costs and whether they are always in stock.
7. Find out how the post-warranty maintenance of the device will take place, under what conditions and in what time frame.
8. Find out who and how trains professionals to work on this device, how many professionals can be trained when buying, under what conditions, whether the training will be repeated if the professional staff in your salon changes and under what conditions.

In conclusion, we would like to remind you that the use of laser rejuvenation techniques requires that beauty salons and clinics have a medical license and specialists who have the right to provide services using equipment of this class - doctors who have undergone special training within the "Standard program of additional professional educationmedicine ".