What are Pigmented Lesions?
Melanin generated in the melanocytes of the skin is the single most important factor that determines a person’s skin colour. It also plays a natural role in protecting the skin against UV rays from the sun.
If melanin cells are exposed to strong UV rays for a long period of time, they generate more melanin in response to protect the skin and prevent cell damage. Pigmented lesions such as freckles, blemishes, sunspots, melasma and so on are brought about by an excessive accumulation of this pigment. Aside from exposure to UV rays, pigmented lesions can also occur through a variety of causes such as aging, heredity, hormones, stress, temperature changes and lack of sleep.
How do you treat Pigmented Lesions?
Pigmented lesions are treated by eliciting either a photoacoustic or a photothermal effect on the pigment molecules that are present within the layers of the skin. This effect is made possible by the application of heat specifically on the pigment and allowing heat to break the bonds of the molecules holding the pigment together, effectively shattering the pigment into smaller particles that the body can get rid of naturally. On some treatments, these broken down particles are brought to the surface of the skin to slough off, on others they are taken out of the body through our lymphatic system.
Different devices approach this outcome in different ways. For instance, the Pastelle Q-Switched utilises very short pulses of the 1064nm or 532nm wavelength to deliver thermal energy to a target without harming the surrounding skin.
The IRIS uses a long pulse duration that elicits more of a photothermal effect that denatures the pigment in the lesions. Freckles, age spots, liver spots and the like all contain melanin, which absorbs thermal energy from the laser and effectively eliminates them. After a certain period of time, the denatured pigment rises to the surface of the skin and scabs off, leaving the skin clear and looking like new.