Laser treatment for pigmented lesions - how does it work?
Pigmented lesions are darker in colour than normal skin because melanin is abnormally concentrated in one area of the skin. Pigmented lesions could be birthmarks, flat moles, naevi or various freckles/sun spots. Some diseases and infections can also cause pigmentation of skin. Lasers work by delivering an intense beam of light that is absorbed by the melanin in the skin. This light is converted to heat and is absorbed by the cells being targeted destroying them, while leaving the surrounding normal skin unaffected.
What are the risks and benefits of having laser treatment?
The results of laser treatment depend on the depth of the melanin and the colour of the lesion and are, to some degree, unpredictable. Trying a test patch is advisable, but may not always be practical if the treated area is very small.
Several treatments may be required. Successfully treated lesions may recur. Some lesions do not disappear completely, but will be significantly lighter in colour after treatment.
Laser treatment may make the underlying skin colour darker or lighter. If the skin is made lighter, this may be permanent. Caution is needed when treating darker-skinned people as permanent hypopigmentation (lightening) may occur. To reduce the risk of pigmentation changes, SFP 30 sunblock should be worn for at least 6 weeks after treatment, and then you should avoid excessive sun exposure for a further 6 months.
Blistering and crusting of skin sometimes occurs. If this happens, you must not pick or scratch the area to avoid permanent scarring.
The laser beam will damage eyes if viewed directly without protection.
Is there any preparation I need to know about?
Avoid the sun for 4-6 weeks before and after treatment, and during any treatment courses. You may develop hypopigmentation (white spots) after treatment if skin is tanned. The use of self- tanning products must be discontinued one week before treatment..
What happens during treatment?
You and the laser practitioner will wear safety eyewear to protect your eyes from the laser light. Your practitioner will guide the laser to the treatment areas with a small handpiece. Each laser pulse may be preceded by a short pulse of cooling spray. A treatment can take as little as a few minutes to as long as an hour, depending on the size of the area being treated. Often the strength of the laser pulse is changed depending on the reaction on skin and patient comfort.
Each pulse of light feels like the flick of an elastic band. Most patients do not find the treatment too painful. Local anaesthetic cream can be used.
What happens after treatment?
Immediately after the treatment, there will be redness and swelling on the treatment site which may last up to two hours or longer. The treated lesion will appear darker in colour and may look shrivelled. This is normal. The area can be cooled using cold compresses. Aloe vera gel is also applied to the lasered area.
What to expect once home?
Some light crusting of the skin may occur. Avoid picking or scratching the treated skin to avoid permanent scarring. The treated area may appear brown, crusty or red for several days or one week. Once the crusting falls off, the skin underneath will be pink.
You can continue applying aloe vera gel or non-scented hypo-allergenic moisturiser to soothe any irritation and to moisturise. Treat the area gently. You may resume use of your usual creams/lotions/make-up once the irritation/redness/crusting clears. Avoid exercise for 24 hours after treatment.
Avoid sun exposure to reduce the chance of dark pigmentation. Always use sunblock (SPF 30 or higher) throughout the course of your treatment. If you do not follow this advice, you may suffer burning, blistering, scarring and permanent pigment changes.