EPILATION, Dr Ferraglio – dentrocasa magazine, November 2015

Currently, the removal of unwanted hair from the body is a worldwide trend and laser photoepilation or other technology based on light is one of the most requested procedures in aesthetic medicine.
According to data from the American Society of Aesthetic Plastic Surgery, epilation was the third most popular non-surgical procedure in 2014 with 828,000 treatments per year, this procedure has steadily maintained the third position for at least a decade.
In Italy, laser hair removal would be in fifth place in the ranking of non-surgical procedures with 24,000 treatments performed in 2014, an increase of 27% over the previous year.
The mechanism of action of laser epilation is based on the principle of selective photothermolysis, written by Anderson and Parrisch in 1983. The main chromophore, i.e. the optical target of the laser is the melanin of the hair follicle, which is concentrated at the root and the stem, structures that act as optical lures for the light ray. However, the biological target is represented by the stem cells located at the level of the follicular papilla and those present in a structure called bulge attached to the hair, these cells, unpigmented, continuously renew the growth of hairs during life.
Basically, the laser beam on the skin is absorbed by the melanin of the hair, the light is transformed into heat and this thermal effect indirectly overheats the noble structures of the hair (stem cells) that are altered until they are totally destroyed. Only in this way is the hair cycle blocked and epilation can be considered really effective.
Selective photothermolysis depends on numerous laser parameters that a medical operator should know very well, among the most important: the wavelength used, the duration of the pulse, the energy density, the size of the emission spot; all these measures, if properly combined, confine the heat in the target chromophore by selectively destroying it and avoiding the dissipation of heat to the surrounding tissues, thus preventing unpleasant side effects.
So there are some key factors for the success of an epilation treatment that go from understanding the anatomy, growth and physiology of the hair, a thorough understanding of the laser tissue interactions and the correct evaluation of the patient, which, inescapably, must consider the skin phototype, the extension of the surface to be treated, the evaluation of the colour and diameter of the hair to be removed. These last aspects will help decide the laser source to be used, provided they are all available to the doctor.
The ideal would be to have different sources at different wavelengths (Alexandrite long pulse 755 nm, Neodymium: Yag long pulse 1640 nm, diodes 800-810 nm) in a multi-purpose centre; in fact, for the laser therapy expert, it is clear that therapy is not only more effective, but it is especially free of side effects when it is more targeted.
Another important factor for success is that of adequate pre and post operative preparation: practitioners should define realistic expectations with patients before starting the treatment cycle. White hairs, fluff and the fine hairs are not responsive to laser treatments as they lack the target chromophore. The skin should not be tanned and the ideal phototype should be the second or third so as to avert the risk of burns, hyper-pigmentation of the skin or even scarring outcomes. Patients should be advised that permanent and complete hair removal is difficult to achieve, but only through multiple treatments can significant long-term results be achieved. The percentage of success also varies depending on the body areas treated, in fact there are areas of the body in which laser hair removal is statistically more effective, for example legs, thighs and groin. The patient should also be advised to avoid UV rays (sun and/or tanning lamps) for at least 3-4 weeks after each laser session.
In conclusion, it is now possible to achieve excellent hair removal results, maintaining high safety margins only by relying on competent professionals, equipped with high-level machinery in multi-purpose structures with the possibility to choose between different possible wavelengths. (Kind collaboration of Dr Alberto Ferraglio)