What are the brown spots on the skin?
The formation of cutaneous spots is caused by an uneven production of melanin by the melanocytes, which release it in the form of small granules that then spread to the superficial layers of the skin. The formation of melanin occurs in reply to external stimuli, like the exposure to ultraviolet rays, and has the purpose of protecting the skin from damage from radiation. Normally, once the stimulus that has induced the production of melanin ceases, the skin tends to regain its uniform colouring. But sometimes the production and the diffusion of the melanin turn out to be excessive and the skin is not able to return to its initial condition.
As time goes by and with the exposure to the sun, brown-coloured spots can form, particularly on the face and hands; the so-called solar lentigo. Furthermore, in time, the pigment of the skin tends to become more and more irregular and this leads to the appearance of brown spots, the so-called lentigo senilis, which are also localized on the back of the hands and on the face.
Where do brown spots on the skin form?
We can have pigmentation due to hormonal modifications, as in the case of oral contraceptives, or replacement hormone therapy in the menopause and finally during pregnancy (melasma). The hormonal spots tend to be more extensive, to be localized on the forehead, on the cheeks and the upper lip and normally get worse with sun-tanning. Another kind of spot forms following inflammatory processes which occur on the skin, or after traumas (post inflammatory hyperpigmentation).
Treatment of brown spots on the skin
It is important to underline that each single spot can be of a different kind, from one to another, even if often they can appear to be connected. These different types of spots require separate diagnoses and consequently different treatments, even if they all have an irregular production of melanin in common and all get worse with exposure to the sun. It is, therefore, of maximum importance to watch out for ultraviolet rays throughout the whole year. Any depigmentation treatment will be short-lived if it is not accompanied by an adequate protection of the skin against ultraviolet radiation. In certain cases the spots can disappear spontaneously (above all post-inflammatory pigmentation), in others treatment may be needed, which can make use of gradually progressive methods, (creams, some peelings, pulsed light) or more aggressive methods (laser).
The creams at our disposal all make use of pharmacologically active substances (they are therefore of an exclusive medical relevance) and have an effect by making use of active principals with a smoothing and exfoliating action (alpha hydroxy acids, retinoids) and the active principals that block the production of melanin (hydrochinone, arbutin, cogic acid, vitamin C, azelaic acid). In this way the cellular renewal is encouraged, whilst at the same time reducing the production and depositing of melanin.
Many of the types of peeling that have a superficial and medium action have the purpose of lessening the pigmentation. The choice of the most suitable type of treatment is up to the specialist on the basis of the diagnosis of the type of spot.
Finally, different kinds of technology are able to assist us in the reduction of the pigmentation. Pulsed light, ablative lasers, ruby and alexandrite lasers are all instruments that are able to treat the various types of pigmentation. Last of all the 1540 fractional non-ablative laser is one of the few lasers with which a clinically significant improvement of melasmas has been obtained.
Melasma (called Chloasma during pregnancy) is a mottled pigmentation of the skin, which is usually localized on the face, to be found frequently in young women. The exact mechanism of the formation of melasmas is not known but there is evidence that the sex hormones (estrogens) stimulate an excessive production of melanin in the skin after exposure to sunlight or to suntan lamps. The lesions appear as brown-coloured spots, which are localized on the forehead, cheeks, on the upper lip, the chin or on the sides or lower portions of the face. In rarer cases the marks are evident on the neck and on the forearms. The pigmentation, which is lighter in the winter, tends to intensify in the summer, with exposure to the sun. Apart from in some forms in pregnancy, in which they lighten spontaneously, melasma usually tends to be chronic and its treatment is lengthy and requires consistency. In fact, the use of aggressive methods generally worsens it and requires treatment based on creams, superficial peeling, or, extremely limited energy when using a laser. Obviously exposure to the sun needs to be eliminated completely.