Laser

Dr.Tim Gianto

Lasers have been around for a long time. They are based on the theory of Einstein in the early 20th century. Theodore Maiman in California built the first LASER (Light Amplification by Stimulated Emission of Radiation) in 1960. After this numerous different types of Lasers where developed and the basis for laser surgery was formulated. The basic design and function of Lasers have remained the same since those early days. There were some new developments in the 1990's incl. pulsed lasers and the Q-Swiched Lasers which have improved the treatment of different skin conditions. Laser resurfacing "the laser peel" has been made possible with the Carbon dioxide (CO2) Laser. There are numerous different lasers that work best on different skin conditions, depending on you individual needs your Surgeon will chose the most appropriate laser.

Before going threw different types of lasers and some of the conditions that laser surgery can treat, it's important for your understanding of laser surgery that you know some basic concepts. Lasers are basically light that travels in parallel and at the same wavelength.. The basic component of light is the photon. The photon that is emitted from the Laser machine has a particular wavelength. The wavelength determine the colour that the laser beam has and this colour can be outside the spectrum that your eyes can see either in the ultraviolet or the infra-red spectrum. The number of photons that are emitted per area unit determine the energy that the laser beam has. When the laser beam reaches an object several things can happen. The laser beam can be reflected off the object, this happens when lasers are aimed at mirrors. The laser beam can go threw the object, this happens when the laser beam is aimed at glass. And finally the laser beam can be absorbed and the energy released, this is what happens in laser surgery. The Laser beam hits the tissue that it is aimed at which causes the energy in the Laser beam to be released and the tissue gets heated up. The laser in laser surgery works by heating up the tissue precisely and thereby destroying it.

Some lasers are used to cut skin, some are used to remove blood vessels, some are used to remove pigment and yet others are used to resurface the skin. How is this versatility possible? How can some lasers specifically target different components in the skin? This is because different tissue components absorb light at different wavelength. Different lasers operate on different wavelength. For example the yellow beam lasers operate on a wavelength of 568 to 585 nm (nano meter). Haemoglobin which is the substance that carries oxygen in you blood absorbs the yellow laser light and heat is developed. As the haemoglobin is contained in red blood cells that circulate in you blood vessels, the heat that is developed destroys the blood vessel. This is very useful when treating conditions involving excessive blood vessels such as port wine stains, strawberry naevus and telangiectasis. Because the haemoglobin absorbs the laser light to a much higher extent than the other tissue components, the blood vessel is selectively destroyed.

Some new concepts in laser surgery have also been developed recently. These have allowed some of the complication of laser surgery to be minimised. One of these concepts is the thermal relaxation time. This is the time it takes the tissue to cool down 50% of the temperature achieved immediately after laser exposure. All lasers work by heating up different components of the tissue and thereby destroying it. If the laser is applied for a long time this heat spreads to the surrounding tissue and destroys components that were not intended to be destroyed. This will cause scarring and a poor result. By pulsing the laser this effect can be minimised. The pulses should be long enough to destroy what you want to destroy but not long enough to heat up the surrounding tissue. The time needed for each pulse is determined by the thermal relaxation time. The Q-swiched lasers were basically developed for this purpose. With this special technology high energy bursts of short duration can be emitted thereby providing highly precise and selective action.

Some common conditions that lasers can be used for.

Laser Resurfacing.

This is also called the "Laser peel". The idea of resurfacing of the skin is to take away the top layer of skin. This top layer is the one that contains fine wrinkles, sun damage and other imperfections. By removing the top layer of skin new skin starts to grow and more youthful looking skin appears. The resurfacing procedure can be either superficial or deep. The Superficial procedures have a quicker heeling time and the final results appear faster but the result is more subtle and the procedure may need to be done several times for the intended result. The deep procedures produce a better long-term result with less of a need to be redone but are more traumatic, with more pain and a longer recovery period.

Other methods of doing skin resurfacing include; chemical peel and dermabrasion. Dermabration scrapes the top layer of skin off your face. It produces good results but has a far higher chance than laser therapy of producing scaring, colour changes and atrophy. Chemical peels include trichloroacetic acid and Phenol peels. Tricloroacetic acid provides a superficial peel but does not eliminate deeper wrinkles or sun damage. The phenol peel provides a more deep peel but has problems with hypo-pigmentation and changing the texture of your skin.

The best method of skin resurfacing seems to be the CO2 laser peel. The operator of the laser can precisely decide how deep the skin peel is going to be and the laser peel is virtually bloodless. You can decide beforehand how deep your peel is going to be and selected reas can also be treated individually. At the end of the procedure the final results can be visualised.

After the treatment you will experience some swelling and discomfort. This may be likened to sunburn. A Crust will appear that you should not pick off as this may cause scarring. After about 10 days you should be free of crusts. It will take a week or two for the results to appear but it may take up to 6 month for the final result to be apparent. As with any surgery there are risk which your surgeon should carefully explain to you.

Removal of vascular lesions

Many vascular lesions cause unsightly cosmetic blemishes. These include portwine stains, capillary haemangiomas, venous lakes, rosacea and spider angioma. All these lesions have in common that they contain blood vessels that cause the unsightly appearance. Laser surgery is very useful for this as it can specifically target the blood components and thereby removing the individual blood vessels in these lesions. A recent development in laser surgery has been the yellow light laser that target these skin lesion more specifically than previous lasers. As with any laser therapy several sessions may be necessary to obtain complete resolution of the problem. Lasers that produce the yellow light include the Argon-pumped Tunable dye laser, Flashlamp-pumped Pulsed Dye Laser, Copper bromide laser and the krypton Laser.

The yellow light laser beam gets absorbed be the red blood cells in your blood vessels and the blood vessels gets destroyed. The final result may take 4-6 weeks to appear and the procedure may need to be repeated. But most of the blemish should be able to be removed.

Tattoo Removal

There are basically two types of tattoos that should be distinguished. These are the amateur tattoo and the professional tattoo. The amateur tattoo is usually done with particles that are much bigger than in the professional tattoo, it is usually also of a single colour. Due to the large particles in the amateur tattoo several treatments may need to be done and full resolution of the tattoo may not happen. The professional tattoo is done with smaller particles and of several colours. Because several different colours are used different lasers may need to be used to remove the tattoo completely. Other problems in tattoo removal are that the particles in the tattoo may change colour. For example a professional colour tattoo may turn black without fading. Selection of the proper laser for different types of tattoos is important. If proper selection is done then complete resolution of the tattoo should be expected.

In Conclusion.

Lasers have a wide area of use. There are several different types of lasers that emit different types of light in different ways. Each type of Laser has its area of uses. No laser is able to do everything. It's therefor important that your doctor selects the proper laser for your condition. If the proper laser is selected the results can be remarkable and well worth trying. Don’t expect lasers to be able to treat everything.