For the treatment of pigments, the understanding of the type of pigment and the location of these pigments are very important and crucial to its treatment. You must have heard another fallacy propagated by some in the beauty industry: “ the more laser you do the more pigments you will get”. This is not an absolute lie but one that doesn’t help any patient. In many cases, only lasers can treat and remove the pigments. We classify pigments into epidermal pigments (superficial) and dermal pigments (deep). Some use the wood’s lamp to differentiate but with experience one can tell the difference.
Epidermal or superficial pigments can be treated by IPL (510nm) or surface acting lasers like KTP 532, Q Switch 532, Pulsed Dye 595. You noticed that the wavelength used is in the 500 nm range. This is because this wavelength attacks epidermal dark pigments effectively. So why do we have some many treatment modalities? Generally lasers are stronger while IPL is more gentle. Each laser type has its unique treatment usage, downtine and risk.
For example, we prefer to use KTP 532 laser instead of the Q Switch Nd Yag 532 laser. Eventhough it’s the same wavelength essentially, the laser pulse mode is totally different and therefore the Q Switched mode is associated with a much higher risk of post laser pigmentation. In terms of downtime, the Q Switched 532 laser results in a burnt scab that takes 3-5 days to clear while the KTP 532 laser has no scabs. But for some pigments, the Q Switch works much better than the KTP laser. Our aim is to use the most appropriate laser with the least downtime and the highest safety factor for each and every pigmentation. Consequently, we grew to use many lasers.
For dermal pigments, we use a different set of lasers, mainly 1064 Q Switched laser and also the 595 Pulsed Dye laser. In some cases, we may have to use some injections into the pigmentation to speed its clearance. Only such lasers can penetrate into the mid or deep dermis to treat such pigments. IPL will never get so deep so its essential useless.
In all these treatments of pigments, we are using the concept of photothermolysis where light energy in the form of a laser beam or an intense pulsed light (IPL) is sent into the skin. The normal skin tissue is much lighter in color compared to the pigment and thus reflects this energy while the pigment absorbs the light energy preferentially and gets burnt in the end. That’s how pigments are removed. In some cases, with a Q Switched laser, the light energy is in the form of a shot gun and the pigments are burst into some pieces, This is called a photo-acoustic effect. With fractional lasers, its yet another form of pigment removal, its by simple pigment reduction as the skin is burnt in columns.
We need to make mention of a special skin condition called Melasma. Its pigmentation that’s developed largely form a hormonal cause and aggravated by sun exposure. We have several patients with such a condition and the pigmentation can be a mix of epidermal and dermal melasma. Its possible to clear the pigments using lasers as mentioned above but the unique situation is that repigmentation occurs very often. Laser and IPL are only able to target the pigments and clear them. They unfortunately cannot prevent the regeneration of new pigments. With Melasma, the regeneration is especially fast due to the hormone effect. Therefore, with Melasma, its especially important to stop the production of pigments by using lightening creams and sunblock. In some cases, we need to do very light laser sessions but weekly to keep washing away the new pigments.
|Last Updated ( Tuesday, 09 December 2014 02:36 )|