What are Fractional CO2 Lasers?

What are ablative lasers?

Ablative refers to lasers that remove or destroy the outer layers of the skin. This occurs when the light emitted by the laser heats the skin to a boiling point, vaporizing the skin cells. The skin will expectedly react to it being burned, therefore healing from these lasers take time (also known as downtime or recovery period). Despite some expected side effects such as redness, swelling, or peeling, the end result is the development of new skin. The laser’s controlled burn causes collagen to be re-deposited as a result of the natural wound healing process, and the dermis (where collagen is located) becomes thicker, improving the apperance of acne scars or wrinkles. One of the most common ablative lasers are the CO2 lasers.

What is a fractional laser?

Fractional means only portions of the skin surface is ablated (removed) by a laser. This is because the emitted laser beam is “fractionated” into a pattern where some parts of the skin are destroyed, while other parts are left intact. This is why patients undergoing fractional resurfacing often have grid-like marks on the face where the red dots represent ablated areas of the skin, while the rest is intact skin. Because of this “selective” type of resurfacing, fractional lasers are safer and better tolerated than regular resurfacing. The healing time is faster and there are fewer complications such as scarring, hyper- or hypopigmentation. The first fractionated laser made was a fractional CO2 laser.

Fractional CO2 lasers

We previously discussed the different types of lasers, their mechanism of action and applications in my Lasers 101 blog post.

CO2 lasers are ablative lasers that can be fractionated or non-fractionated, and both settings can be done by the same machine. CO2 lasers targets water, and because our skin contains a very high percentage of water, these lasers can effectively remove benign raised lesions (non-fractional mode) and improve acne scars and wrinkles (fractional mode). We will focus on the latter on this blog post.

Fractional CO2 lasers create zones of microinjury that stimulate the production of collagen. This production of collagen can replenish lost collagen, leading to an improvement in acne scars, wrinkles or other skin textural changes due to sun damage. Fractional CO2 lasers do notimprove conditions caused by abnormalities of the blood vessels (e.g. telangiectasia, spider veins, hemangioma).

When will I see results?

Fractional CO2 laser treatments are customized for each patient. Treatments can be deeper, requiring a longer recovery period, or shallower, with less downtime. In general, better results are obtained with deeper treatments. The intensity of treatment depends on many factors including the severity of the skin condition, patient’s lifestyle/occupation (may affect the desired duration of the downtime), skin type (particularly skin pigment), among others. You may see some results within a few weeks but full results are evident after 3-6 months because your body is still producing new skin and more collagen.

How are fractional CO2 laser treatments performed?

This is the procedure at the Levana Dermatology Clinic: The treatment area will be cleansed and a numbing cream (topical anesthetic) will be applied. This will be removed after about an hour. Laser treatment is then performed. A protective eyepiece will be used during the entire procedure. Patients will be asked to keep their eyes closed.

What happens after the laser treatment?

After the laser treatment we will cool your skin down and apply moisturizer and sunscreen on the treated area. You may need to apply a moisturizer or other prescribed skin care products at home. Sunscreen use is a must.

During the first 24 hours after treatment, the treated area may experience redness, swelling and feel as though it is throbbing. I suggest patients apply ice packs on the treated area about 5-10 minutes per hour for the first few hours after the treatment. Your skin will peel for the next few days (average 2-10 days) and will be pink for a few weeks (average 2-6 weeks). Again, this depends on the settings of your treatment.

How many treatments will I need?

Your dermatologist will help you determine the number of CO2 laser treatments you will need. The number of treatments depends on the settings used, which, as I mentioned, are determined by the extent of your skin condition, skin type or patient preference. With more aggressive settings, many patients notice significant improvement with fewer treatments.

Are there contraindications to fractional CO2 laser treatments?

Yes. These include use of medications that increase photosensitivity, use of some anticoagulants, use of isotretinoin in the previous 6-12 months, chemotherapy, history of scarring or difficulty in healing wounds, history of bleeding disorders, and pregnancy.

What are the side effects?

A board-certified dermatologist with good experience using fractional CO2 lasers can decrease the incidence of complications. Here are some side effects reported in literature:

  • Pain or discomfort – most patients report some discomfort ranging from mild to moderate during the procedure. If the patient is too uncomfortable, we will adjust accordingly.
  • Redness – although some redness is expected, prolonged redness can be seen in in patients who have a prior history of flushing or have dilated vessels on the surface of the skin.
  • Swelling – there will be swelling of the skin immediately after laser treatment. This is temporary, often resolving within one to seven days.
  • Peeling – there will be peeling of the skin a few days after laser treatment. This is temporary, often resolving within two to ten days.
  • Pigment changes –rarely, the treated area may heal with increased or decreased pigmentation. This occurs most often in darker skin two to six weeks after treatment. This usually fades in three to six months, though rarely pigment changes can be permanent. This is why it is very important for the dermatologist to assess if you are a good candidate for laser therapy prior to undergoing the procedure.
  • Scarring – there is a small chance of scarring (hypertrophic scars or, very rarely, keloid scars). It is important to report to your dermatologist any prior history of scarring.
  • Infection – occurs rarely but is adequately treated with antibiotics.

I am often asked if fractional CO2 lasers completely heal acne scars. I always explain that it is rare to experience 100% resolution, but I have seen 30-70% improvement in my patients. It is very important to remember that patients respond differently to treatments, and that laser treatments take time to work and often require more than one session to achieve full effects. I find it essential to set my patients’ expectations going forward.

It is best to consult a board-certified dermatologist to determine if you are a good candidate for laser therapy. Your dermatologist can further explain the treatment’s advantages, disadvantages and side effects, and design a skin care regimen while undergoing laser therapy.

Skincerely yours,

Dr. Mara Evangelista-Huber

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