Laser techniques in the correction of hypermelanosis

Sergey Sukhoversha is a surgeon, exclusive distributor of Sciton Inc in Ukraine (Ukraine, Kiev).

Pigmentation disorders

Hyperchromia, hypermelanosis or melasma are different names for clinical variants of impaired melanogenesis in the direction of increasing skin color. Among them, primary (congenital and acquired) and secondary (post-infectious and post-inflammatory) forms are distinguished.

Acquired hypermelanosis is a pathology in which melanogenesis is activated under the influence of various unfavorable factors. Among them may be physical factors (mechanical, temperature, radiation), chemical, toxic (occupational and medicinal), diseases of internal organs and systems, infectious and parasitic diseases, metabolic disorders, etc. All this pathology is divided into limited and diffuse forms.

In this article we will consider the most common forms of hypermelanosis - melasma and chloasma.

Chloasma (Chloasma, Melanodermia uterina) is a hyperpigmented spot of dark yellow or dark brown color, irregular in shape, with sharply defined boundaries, of various sizes and prone to merging into large foci. Most often it is localized in the forehead, cheeks, temples, and less often - eyelids and chin.

Chloasma is the most common type of limited hypermelanosis, since it occurs in almost every woman during pregnancy, often along with other hormonal pigmentations characteristic of this period (along the midline of the abdomen, around the nipples and genitals). This allows us to interpret this phenomenon as chloasma of pregnant women ( Ch. gravidarum ). As a rule, it disappears with the onset of the first menstruation, although it can often persist for longer periods, in some cases - until menopause and even after. This also includes the so-called pregnancy mask, in which, in addition to the usual areas, the skin of the eyebrows, upper and lower eyelids is intensely colored, giving the face a unique appearance.

Among other types of chloasma, there are forms that occur without any connection with pregnancy due to pathology of the uterus, appendages ( Ch. uterinum or Ch. ovariogenes ), and sometimes when taking contraceptive drugs.

Melasma (M elasma) is a benign hypermelanosis of skin areas exposed to sunlight. Melasma appears as symmetrically located solid or pinpoint areas of skin with hyperpigmentation. On the face, melasma is most often localized in the upper part of the cheeks, the bridge of the nose, the forehead, and the upper lip. People with darker skin or a good reaction to the sun (who tan well) are more likely to develop melasma, with women being affected much more often than men (20:1). Melasma appears between 30–40 years and is most often localized in the upper part of the cheeks, on the bridge of the nose, forehead, and upper lip. Melasma darkens when exposed to sunlight or any other source of ultraviolet radiation.

Depending on the depth of localization

Diagnosis of the depth of localization of hypermelanosis is of practical importance. This determines the choice of local treatment technique (Table 1).

Table 1. Differential diagnosis of hypermelanosis depending on location

To diagnose the type of hypermelanosis, polarized light systems are used, which make it possible to clearly determine the depth of the pigment. As is known, with a decrease in the level of insolation, the intensity of hypermelanosis staining decreases. Syris v300 polarized light systems make it possible to diagnose hypermelanosis that is difficult to see with the naked eye.

Treatment methods

Melasma is quite slow to treat and requires long-term qualified medical supervision.

Among the main approaches, the following points can be highlighted .

• Cancel hormonal contraceptives if a woman is taking them.
• Avoiding medications, dietary supplements, and foods that have photosensitizing effects.
• Apply sunscreen all year round. Sunscreens should have a broad spectrum of protection - UVB+UVA.
• Refusal to use powerful skin cleansers (often used to treat and prevent acne).
• Careful use of cosmetics containing retinoids, α-hydroxy acids, β-hydroxy acids (AHA, BHA). Mandatory consultation with a specialist when using such cosmetics.
• Avoiding dry skin as the skin produces its own SPF.

The use of cosmetics that inhibit melanogenesis:

1. hydroquinone (use prohibited in Europe, contraindicated during pregnancy and lactation);
2. kojic acid;
3. azelaic acid (can be used during pregnancy).

Topical corticosteroids provide a fairly rapid clinical effect, especially in cases where the appearance of melasma is associated with inflammatory phenomena in the skin.

Exfoliating techniques:

1. Chemical exfoliating agents:
   • salicylic acid;
   • hydroxy acids - glycolic, lactic, etc.;
   • topical retinoids – tretinoin.
2. Microdermabrasion. Its disadvantage is the uneven impact in depth. Laser peels with adjustable depth are preferable.
3. MicroLaserPeel (laser peels) – preference should be given to “cold lasers” (erbium).

If melasma is localized in the dermis , the best results will be achieved by fractional skin rejuvenation with an erbium laser (Er:YAG 2940 nm).

If melasma is of a mixed type , then the best results will be shown by a combination of superficial erbium laser peeling with fractional erbium laser rejuvenation or a combination of IPL photorejuvenation with fractional erbium skin rejuvenation.

• Methods that destroy pigment - photorejuvenation IPL, BBL.
• Oral intake of proanthocyanidins and carotenoids - lycopene (Imedin).

The effect in the treatment of melasma is achieved slowly. Complete relief from it can be achieved only in 30% of cases. In other cases, stable remission is achieved, but with contact with the sun or changes in hormonal levels, regression of symptoms is possible.

Laser correction

Photorejuvenation with broadband pulsed light. Melanin absorbs the visible spectrum of light well. The emergence of hardware photorejuvenation techniques has improved the quality of treatment for hyperpigmentation. Selective absorption of energy by melanin leads to the destruction of cells containing excess pigment and melanocytes. For the purpose of photorejuvenation, filters of 515, 530 and 560 nm are used. This technique gives good results for superficial epidermal hypermelanosis.

Laser peeling. The use of laser techniques for melasma has been sharply limited until recently. The main reason for this is post-inflammatory hyperpigmentation, which often develops after laser peels. Laser peeling with micron precision allows you to measure the depth of removal of epidermal cells. It is known that the thickness of the surface layer of the skin (epidermis) is 100 microns. The erbium peeling procedure allows you to remove layer by layer of epidermal cells with an accuracy of 4 microns, which is comparable to the size of the cell. The advantage of erbium laser peeling is the absence of heating of skin cells, therefore, with erbium peeling, melanocytes are not stimulated and post-inflammatory hyperpigmentation does not develop. The high degree of absorption of the laser beam by water contained in the cells causes their immediate removal from the surface of the skin, without heating or transferring heat to neighboring cells. The absence of pronounced peeling after the procedure is due to the fact that some of the cells are removed during the procedure. Peeling begins on the third day and ends by the fifth day.

Fractional thermolysis in the treatment of hypermelanosis. Particularly difficult is the treatment of hypermelanosis of the dermal localization. For hypermelanosis with deep pigment, Jaggi Rao, head of the department of dermatology at the University of Alberta (Edmonton, Alberta, Canada), recommends combining MicroLaserPeel with fractional thermolysis with an erbium laser. This procedure creates microchannels to a given depth, which allows you to achieve good results in hypermelanosis that cannot be treated with conventional methods. Unlike non-ablative fractional rejuvenation (fractional techniques of the 1st generation) and fractional rejuvenation with CO2 lasers, the method of fractional thermolysis with an erbium laser creates microchannels of a given depth without heating neighboring cells and without causing post-inflammatory hyperpigmentation. The second, no less important point in the treatment of melasma is the effect of microfenestration , when, unlike CO2 lasers, coagulation of the walls of microchannels does not occur, and the intercellular fluid can be freely released. This removes excess pigment from the intercellular space. Jaggi Rao considers the method of fractional thermolysis with an erbium laser promising for hypermelanosis that cannot be treated with conventional methods - for melasma of dermal and mixed localization.

Despite significant advances in photorejuvenation techniques, laser peels and fractional techniques, during the treatment of hyperpigmentation one should not forget about the use of sunscreens and drugs that inhibit melanogenesis.

First published: KOSMETIK international journal, No. 4 (46), 2011