1. Ruby laser (694 nm)
2. Alexandrite laser (755 nm)
3. Diode laser (800 nm)
4. Nd:YAG laser (1064 nm)
5. Intense pulsed light (590-1200 nm)

Ruby laser: emits 694 nm red light. In hair removal a longer pulse and lesser potency are used. Ruby laser is used occasionally for fair phototypes (I to III) with dark hair.

Alexandrite laser: emits a wavelength of 755 nm. It penetrates deeper than the ruby laser, which means it can be used for darker phototypes (up to phototype IV). The pulse may be fixed or variable and the spot size may reach 18 mm. Some systems incorporate a scanning system that enables the treatment of wider areas. Gas, gel or cold air are used as cooling systems. One of the advantages of the alexandrite laser is that it is quite fast. Some systems require shaving of the area. Its disadvantages include not being the most appropriate for very dark phototypes (V) or for facial hair removal.

sistemas

Diode laser: it emits a wavelength of 800-810 nm and enables the variation of pulse duration. The spot size is 9 x 9 mm. As long as the hair is dark, darker phototypes (V) can be treated without producing a lesion in the epidermis. The greater the wavelength is, the lesser absorption of melanin, requiring more energy. The cooling system consists of a sapphire in the hand piece that comes into contact with the skin. Shaving of the area is required.
The diode laser’s main advantage is that it allows the treatment of darker phototypes preserving the epidermis. Its basic drawback is that it’s a slower system due to the small spot size. It is not used for facial hair removal because of its wavelength and need of previous shaving of the area.

Nd:YAG laser: It emits a wavelength of 1064 nm through Q-switched pulses or long pulses. This wavelength is mildly absorbed by the pigments, which enables the treatment of all skin types. However, it is less effective. The lesser absorption of melanin requires the use of high fluencies although it can be used to treat darker phototypes without any risks. Long pulse systems emit single pulses of variable duration and the spot size measures 2 to 4 mm. Some systems require the external application of carbon particles to increase their absorption.

Soprano Laser, Super Hair Removal technology SHR A new technique based on the Extended Theory of Selective Photothermolysis and in its Thermal Damage Time (TDT) concept is now available. It is known as Super Hair Removal (SHR) and is currently being applied exclusively with the Soprano Laser Diode. The fundamental key to this technology is the Soprano Laser, a conventional laser diode unit that works with the traditional laser diode hair removal techniques as well as the Super Hair Removal (SHR) mode: The SHR mode works at 10 Hz, that is, 10 pulses per second. Its application is based on a sweeping motion over the skin at a rate of 10 cm/second, rather than concentrating the pulses in one area, with 6 to 8 sweeps over the region. This makes the increase in skin temperature more gradual and from the inside to the surface which avoids the risk of superficial burning. The gradual heating of the skin applying energy in several sweeps provides greater tolerance in patients sensitive to the heat produced by the impact of conventional laser hair removal. Therefore, treatment is somewhat slower due to the number of sweeps required. IML finds this unit very interesting for body hair removal but not for facial hair removal and it is of special interest in situations of highly pigmented skin given that, to date, patients with recent tans and phototype V and VI skins have been treated with no side effects. This technology has proven its efficiency in extreme situations that were previously difficult to treat: 1.-Very darkly tanned patients or with recent tans, either natural or with UVA rays. 2.-Phototype V and VI skins (very dark or black skin) IML is currently carrying out efficiency and security tests with these extreme situations, resulting in very good outcomes. Better than expected. These results will be fully presented in February 2008.

Intense pulsed light: It emits light with a 590 to 1200 nm wavelength. The pulses are generated by a lamp or pulsed flashlamp. Filters are used to determine the most appropriate spectrum according to the patient’s skin and hair type. Short filters are used (590, 615) for fair skin and fine hair. If the skin is tan and the hair is dark, longer filters are used (645, 695, 755). Intense pulsed light is applied to the patient with a quartz guide. It enables the use of multipulses and the variation of pulse durations and the intervals between each. This makes many combinations possible and is especially useful in facial hair removal. Most systems include software which automatically selects the necessary parameters, but the doctor can modify them manually (users parameters). The cooling system consists of gel (at 4º C) which improves the light’s distribution and cools the epidermis. It is a very versatile system that requires skilled training and knowledge of the technique.

Incoming search terms for the article:

The hair follicle contains melanin, a natural chromophore. Other chromophores in the skin are water and haemoglobin. The lasers used in hair removal target melanin and must emit light with an appropriate wavelength for high absorption by this natural chromophore, but minimal absorption by the rest. As light energy is absorbed by the melanin it is transformed into thermal energy, meaning heat which will destroy the hair follicle.

Nowadays, it is still unclear which specific site has to be destroyed to avoid hair regeneration. Studies postulate that the destruction of the papilla and matrix cause a delay in follicle growth. On the other hand, the destruction of stem cells in the protuberance area at the interface between the external radicular sheath and connective tissue causes a permanent epilation.
depilacion

Parameters to be considered in photothermolysis:

Wavelength: is the electromagnetic spectrum frequency band where the laser emits. It is measured in nanometres (nm). The greater the wavelength the greater penetration in the skin and the lesser absorption by chromophore. Wavelengths closer to infrared (700-1400nm) are more appropriate for melanin.

Thermal relaxation time: is the amount of time necessary to reduce by 50% the temperature generated by light emission on the targeted tissue or structures. Optimal pulse duration must be between epidermal relaxation time (3-10 milliseconds) and hair follicle relaxation time (40-100 milliseconds).

Dosage or fluency: is the relationship between available energy and the surface covered by the irradiation beam, measured in Joules/cm2. Efficacy is proportional to dose.

Pulse duration: is the duration of energy emission. It is measured in nano, micro or milliseconds. Pulse duration has become greatly important after Altshuler postulated the amplified theory of photothermolysis. This theory calculates the ideal pulse length for a target at a distance from the heater, considering how long it takes for heat to scatter from the heater to the outermost part of the target. The heater would be what absorbs the energy (melanin), and the target, the object to be damaged by the heat (protuberance stem cells). According to this theory, thermal damage time is the irreversible damage time of the most external part of the target. For a follicle of 200 micras it would be 170 ms.

Number of pulses: the fractioning of energy into several pulses allows the application of larger doses while preserving the epidermis.

Pulse intervals or “pulse delay”: time between pulses.

Size of the irradiation beam or “spot”: the greater the surface, the greater the penetration and efficacy. When a small spot is delivered there is greater scattering of photons in radial direction, without reaching the hair bulbs with a decrease of fluency. To avoid the effect of radial scattering the spot size must be bigger than the light’s penetration depth into the tissue (5-10 mm).

Pulse frequency: shot speed (number of pulses per second triggered), which reduces the duration of the sessions. It is measured in Hertz.

Laser is the advanced technology of light aligned in one direction only used for medical purposes for several decades. Its application in laser hair treatment has the ability to penetrate the surface layer of the skin and is absorbed by the melanin is concentrated in hair follicles. Laser to increase the temperature of melanin and produce thermal injury resulting in the gradual elimination of the hair, but without causing injury to the skin surface. Juan Ruiz Alconera, we capillaries Medical Corporation in the following article detailing why revoke laser.

- Laser Diode (Lightsheer): The laser has many applications and skins are most often used to treat skin types from I to V and the brown and dark skin.

- Alexandrite laser (Candela): A special laser for hair removal and is very effective for skin phototype II to IV, or dark brown hair. The difference between this laser is that it has a cooling system by a shot of ice, which prevents overheating the skin, reducing pain sensation.

- Intense Pulsed Light IPL light emitting mixed noninvasive travel in all directions and is composed of various wavelengths of photons that travel to some, it is the team that controls what happens just a few types of light filter function to paste. Its main advantage is flexibility and therefore we can treat more types of skin and hair.

Enjoy a facial and see the wrinkles disappear a few weeks later.

Here is the source of the world youth waiting for, “says dermatologist Douglas Hamilton in Los Angeles, California.Six years ago, began the soldier’s claim that Americans make pilgrimage to the doctor to remove wrinkles with lasers.But the early treatment had both advantages and disadvantages.

Admittedly, patients received less pronounced wrinkles, but they also received second degree burns and persistent redness after treatment with carbon dioxide laser or erbium laser. Enthusiasm waned.

- I did a laser treatment around the mouth and was very hurt by burns afterward, “says Joyce Uro, 62, who could not use makeup for several weeks after surgery, and then it was an embarrassing redness in a full year.
Lasers that do less harm

- That I had fewer wrinkles seemed simply not worth it, I thought.

Over the past year has focused on the development of lasers designed to create as little damage as possible reactions.

- The last of them, lite, really impresses me, “said Douglas Hamilton dermatologist in Beverly Hills, California.

- My patients experience no pain whatsoever, either during or after the 30-minute reading. They may not even red complexion. There are no side effects at all.

Collagen production is increasing

The only thing that happens is that the dermis layer of skin is heated in such a way that collagen, which gives skin its youthful vigor, increase their natural production. It takes in turn remove small wrinkles around the eyes, the mouth and forehead.

Where the old burned lasers resulted in smoother power directly rather let the results are slow in coming with nLite.

- It can take between one and three months before the wrinkles start to even out, “says dermatologist Douglas Hamilton.
Continues for six months

- It depends on how long it takes for collagen production to get started. Sometimes you also need to make the reading to get really good results. But the improvements will continue to be for a period of six months, approximately.

After puberty, the human skin loses one percent of its collagen each year. Over time, makes the increasing lack of resilience to the skin becomes loose and wrinkled.

- That we can increase production again, and thus the very fact of youthful skin, is pure sensation, “said Douglas Hamilton.
- Now we can also treat virtually all skin types. NLite is particularly appropriate for sun-damaged skin, small delicate crow zoo wrinkles. Deeper wrinkles in the mouth or between the eyebrows, you can not delete.
Treatment for 18 000

The secret behind the latest laser is a light.

- This is a brand new flash bulb of Polyester-type, “said Douglas Hamilton.
- Thanks to the new lighting technology, the skin does not need to heat up as much as they had to before to get results. The light acts directly on the governing production of collagen, instead of burn away layers of the skin.

Tastes like it so much does it cost, of course. In California, patients pay 12 000 Swedish crowns for a local treatment in the face, and 18 000 kronor for the whole face.