Laser treatments in skin care are in great demand due to the superior results they have produced. Today lasers can be used to treat a large number of skin abnormalities. Laser treatment can also improve the cosmetic appearance of the skin.

Pigmented skin lesion laser removal

These lesions are a very common skin disorder causing physical as well as emotional suffering due to disfigurement.

Laser treatment targets the skin melanin to remove the pigmentation at affected sites, without depigmentation of nearby untargeted sites. Today, laser treatments based on the principle of selective thermolysis give better results.

Lasers with narrow pulse widths and wavelengths between 600 to 1200nm have more penetration and selective destruction. Although QSRL, operating at these parameters, was found to be melanin dependent and specific, it is as effective as or better than PDL in treating most lesions. Overall, QSRL has been found unmatched in its effectiveness and versatility in treating almost all kinds of pigmented lesions.

The QS- Nd: YAG laser, with high powered and narrow pulse widths, is very selective, and effective in superficial epidermal lentiginous lesions, freckles and tattoos. The side effects are minimal.

The 760nm alexandrite laser was designed to penetrate the dermis. It has proved surprisingly effective in post-inflammatory hyperpigmentation, although at the wavelength it operates, melanin targeting should be less selective.

Laser skin resurfacing

Laser skin surfacing is done mainly to improve the cosmetic appearance and, especially, to achieve facial rejuvenation by replacing old skin with new healthy skin. It also removes scars left by previous surgery or trauma.

CO2 laser was first used for skin resurfacing with good effect, though at the risk of thermal injury. Advanced laser technology has now reduced the risk of scarring. The new Ultra pulsed CO2 has proved effective in treating ageing skins. Currently, continuous and pulsed CO2 lasers are used for this treatment.

Er: YAG laser is being evaluated and may be effective in superficial neck or eyelid skin.

To obtain optimal results, the pre-treatment and post treatment of the skin is important, especially with dark skins.

Complications of laser skin resurfacing include infection, contact dermatitis, swelling depigmentation and scarring.

Laser scar removal

In this procedure, only the improperly healed scars that cause pus oozing, pain, disfigurement or functional impairment are removed. These are the hypertrophic, atrophic and keloidal scars. These scars are, however, not life threatening.

Scar removal by modern lasers is better compared to earlier treatments. The earlier CO2, argon and Nd: YAG lasers were discontinued due to unsatisfactory results and the risk they posed to the surgeons.

The 585 nm flash-pumped PDL gives better results in hypertrophic scars and scars in dark skinned patients. Pruritis in some scars show improvements with combined therapies, such as, PDL with intralesional corticosteoids and PDL with CO2 lasers.

Today, ablative and non-ablative laser systems are being used to treat atrophic scars that traditionally, have been difficult to remove. In ablative systems, the latest CO2 laser gives more predictable and reproducible tissue vaporization. The pulsed Er: YAG lasers, although 10 times more selective than CO2 lasers, produces less clinical improvements. Er: YAG is recommended for superficial atrophic scars

Non-ablative systems have recently become popular due to mainly little or no downtime involved. The Nd: YAG was the first such laser system developed for non-ablative treatment and has been successful in treating acne scars and improving skin textures.

Laser tattoo removal

Since pigments are used to create tattoos, laser treatment selection depends on the color of the pigment being removed. Q-switched lasers have become and remain the mainstay of tattoo removal.

The Q-switched ruby laser has proved very effective in removing blue and black tattoos. Higher fluences cleared more tattoo.

The Q-switched Nd:YAG laser can operate at 1064nm and 532nm wave lengths. This allows it to treat dark and blue pigments at 1064nm wavelength and red and orange pigments at 532nm wavelength.

The Q-switched alexandrite laser operating at 755nm wave length falls between the ruby and Nd:YAG lasers. It is therefore able to remove, besides black and blue pigments, also green pigments. Green pigment is most difficult to remove. The alexandrite laser is the treatment of choice in green pigments.

Low energy laser treatments

The effect of low energy lasers on biologic tissues needs further investigations. Initial, flawed studies produced conflicting results and generated controversy. The best-understood area is only the basic science data.

Earlier it was believed low energy lasers act by photochemical reaction. Many studies reported that low energy lasers had a healing action but the mechanism remained unknown. Animal studies showed increased collagen formation. Some studies indicated a role for the immune system where lymphocytes and macrophages seemed to play a role. Studies showing that macrophages, irradiated by low energy lasers, speeded up wound healing by speeding up the proliferation phase of repair were contradicted by other studies. Even reports of the wound healing effects of low energy lasers have been contradicted. More studies are therefore needed to give any definite view on the subject.

Laser hair removal

Laser hair removal is based on the principle of selective photothermolysis. The targeted chromaphores are the endogenous hair melanin or an exogenous, artificially introduced chromaphore like, carbon particle.

Lasers offer a relatively safe, effective and rapid hair removal. Numerous studies have confirmed their benefits. However, current hair removal laser tecnology largely benefits those with dark hair and fair skin. Use of longer wavelengths, longer pulse durations and cooling devices may soon allow hair removal in dark skinned individuals. Removal of light colored hair will be the next goal.

Side effects include pain during and after treatment. Children are likely to show poor tolerance to some laser treatments. Edema, erythema and pigmentary changes, especially in dark skinned patients can also occur.

Conclusion

Despite its undoubted achievements, laser therapy is still evolving. It is now being increasingly felt that for proper management of patients, a clear understanding of the present knowledge of laser physics and laser tissue interactions is vital. Hopefully, this area will, in the future, get as much attention as research on laser.