Using laser treatment to eliminate keratosis pilaris.

The keratosis pilaris is a harmless and very common skin inconvenience : it is indeed estimated that it affects between 50 to 80% of teenagers and up to 40% of adults worldwide. This condition causes the emergence of follicular plugs, taking the form of small hard bumps on the skin surface. Most often localised on the arms, calves and thighs, these imperfections can in some cases reach the face or the scalp.

The small bumps associated with keratosis pilaris are typically colourless and surrounded by a slight pink hue in individuals with fair skin, and a brown halo in those with darker skin. While keratosis pilaris is predominantly a cosmetic inconvenience, it can sometimes be accompanied by a mild itch. It is then important to do one's best not to scratch, as this could lead to a mild inflammation.

Several studies have demonstrated a high efficacy of laser treatments in the case of keratosis pilaris. Painless and quick, these treatments provide a real improvement in skin texture after just a few sessions, smoothing the skin's surface while eliminating the small bumps characteristic of keratosis pilaris. There are several types of lasers, all with relatively comparable effectiveness:

• The Nd:YAG laser.

  The Nd:YAG laser is made up of a yttrium aluminium garnet (YAG) crystal doped with a neodymium ion. This laser, with a beam wavelength of 1,064 nm, has good skin penetration. However, the short-term appearance of redness, itching, and swelling are common side effects.

  Among the studies that have examined the effectiveness of this laser in treating keratosis pilaris, one can mention that of LEE, conducted in 2011. Over several weeks, 12 participants with keratosis pilaris underwent a Nd:YAG laser session every two weeks. After 10 sessions, the researchers noted a more than 25% improvement in skin texture for 11 patients. This even exceeded 50% for half of the patients.

• The CO2laser.

  CO2 lasers are ablative lasers that utilise carbon dioxide. Used since the 1990s in dermatology, their operation is based on the excitation of CO2 molecules when they are exposed to infrared radiation. The wavelength emitted by CO2 lasers is 10,600 nm. This type of lasers generally results in very few side effects.

  Furthermore, CO2 lasers have shown good efficacy in treating keratosis pilaris. Several studies have demonstrated that a single session of CO2 laser treatment can, on average, achieve a 50% improvement in skin texture.

• Pulsed light.

  Just as with traditional lasers, the light energy emitted by pulsed light is converted into thermal energywhich allows for the removal of the excess keratin characteristic of keratosis pilaris. However, unlike lasers, pulsed light delivers multiple wavelengths in each pulse (polychromatic light) instead of a precise wavelength. Filters are sometimes used to further control the emitted wavelength.

  Multiple sessions are required to maximise the effectiveness of pulsed light. A study has notably demonstrated an average improvement in skin texture ofapproximately 30% after 3 sessions of pulsed light in individuals affected by keratosis pilaris.

• The diode laser.

  The diode laser emits a wavelength of 810 nm and targets hair follicles specifically to unblock them. The principle of the diode laser also relies on its ability to emit photons that will be converted into thermal energy in the hair follicles, in order to eliminate excess keratin. A few studies have looked into its effectiveness in cases of keratosis pilaris. One of the most recent involving 18 patients showed that after three sessions of diode laser, the skin texture of the individuals had improved by an average of 50%.

Please note : although laser treatments generally provide satisfactory results for keratosis pilaris, it's important to understand that the results are rarely permanent. Indeed, when the treatments are discontinued, a relapse is usually observed.