Laser exfoliation can cause side effects, although they are milder and less likely with non-ablative methods than with ablative methods. Almost any type of laser therapy can cause burns, scarring, dispigmentation, eye injuries, and infections. These complications are the result of selective photothermolysis and, in some cases, can even be used for the benefit of the physician, for example, to reduce hyperpigmentation in melasma. When a laser acts on a chromophore, the molecules absorb energy and heat the surrounding tissue.
To reduce the risk of complications from excessive thermal injury, many lasers use pulses with durations shorter than the thermal relaxation time of the target tissue, which is the amount of time needed for the tissue to cool down to a basal temperature. The goal of selective photothermolysis is to provide sufficient energy to destroy the chromophore without damaging surrounding tissue. It follows that surrounding non-target tissue can therefore be injured by overheating. Burns can result from prolonged pulses, excessive fluence (the amount of energy supplied to the target area) and inadequate cooling.
The risk of burns is greater for lasers that use a continuous beam rather than a pulsed or fractured one. Newer devices reduce the risk of complications by emitting beam pulses in a range of milliseconds to nanoseconds, using multiple fast bursts on an almost continuous basis, or using extremely short pulses with high powers to allow adequate thermal relaxation. Hyperpigmentation and hypopigmentation after laser treatments are comparatively common complications, with hyperpigmentation being more common. The risk of dispigmentation is greater in people with darker skin (Fitz Patrick type III-VI) or who are excessively tanned.
It can be reduced by avoiding sun exposure before and after laser treatments and by using a fractional laser delivery system or cooling devices. However, ironically, overuse of cooling can cause inflammation and also lead to hyperpigmentation. Hyperpigmentation may be due to the accumulation of extracellular melanin due to the destruction of melanocytes or to increased melanin production due to post-treatment inflammation. As such, it doesn't usually last more than three to four months.
Hyperpigmentation is usually best treated with 4% topical hydroquinone, a whitening agent, but it can also be treated with superficial chemical peels or concealment with cosmetics. It's also helpful to avoid exposure to sunlight; for this reason, it's best to avoid laser facial rejuvenation, especially full-field ablation, during the sunny summer months. Burns are caused by overheating of the tissue due to excessive heat generation or insufficient cooling. Proper patient selection and conservative environments reduce the risk of adverse outcomes. Testing the configuration on a small patch of skin two to three weeks before the main treatment also reduces the chance of developing complications; this technique is often employed in laser hair removal.
During treatment, an indication of excessive fluence and, therefore, of excessive heating is the graying of the tissue, which is more evident during non-ablative vascular treatments, in particular pulsed dye therapy for erythematous lesions or scars. If graying occurs, the procedure should be discontinued and the settings and cooling systems reevaluated. Most laser devices have fail-safe systems that prevent more energy from being supplied than the settings indicate, even in the case of that a malfunction occurs. However, a laser can supply less energy if it malfunctions, which can cause the rating to adjust to incorrect settings and then cause excessive fluence later on, after the device has been repaired.
For this reason, it is essential to apply conservative adjustments in the first treatments after a qualified technician repairs the laser. When burns occur, bleeding crusts and ulcerations may appear several days after treatment and may be warning signs of additional complications, such as scarring and dispigmentation. Excessive overlap of treatment areas can cause burns and dispigmentation, but too much space between treatment areas can cause visible areas of untreated skin to appear. Scarring and dispigmentation may appear weeks or months after treatment.
Proper technique and conservative adjustments are essential to reduce the risk of burns. When using a vascular laser, it is important to keep in mind that more erythematous lesions have higher concentrations of chromophores (oxyhemoglobin) and, therefore, will absorb more laser energy than less erythematous lesions; therefore, lower settings are effective for treatment. Likewise, lower adjustments are recommended when treating an injury with the underlying bone, such as on the forehead or orbital border, because energy will reflect back into the bone and go back through the target tissue. In addition to adjusting the power supply settings, several cooling devices, when used properly, also reduce the risk of skin burns. Burns that follow laser therapy can be treated with immediate cooling and then with mild emollients and topical steroids to promote re-epithelialization.
Antibacterial prophylaxis for laser rejuvenation is controversial. If an infection is suspected, the culture threshold should be low, but it is rare that antibiotics are routinely prescribed before laser rejuvenation. Because of the risk of scarring, antibiotic therapy should be initiated promptly if a bacterial infection is suspected. Empirical antibiotic treatment should include Staphylococcus aureus, such as doxycycline or trimethoprim-sulfamethoxazole, but ciprofloxacin may be necessary if cultures reveal the presence of Pseudomonas aeruginosa.
If the patient does not follow an adequate cleaning regimen after ablative laser therapy, there is a possibility of bacterial infection. In addition, if appropriate antibiotics are not prescribed after some laser skin therapies, it can lead to infection. Inappropriate use of lasers can cause changes in skin pigmentation. Hyperpigmentation causes pink, red, or brown spots on the face.
Hypopigmentation removes natural skin tone. It is possible that any of these conditions can be rectified with additional laser therapy. Keep in mind that the risk of injury from laser therapy can occur with any skin tone. Therefore, you should feel comfortable and confident about who is administering the laser treatment.
Choose a dermatologist or board-certified expert who is familiar with treating different skin tones. Burns occur when the skin has absorbed too much heat or energy. Laser treatments are not the same for everyone and the settings used for each individual will vary depending on a few things. One of them is their complexion, a person with a darker complexion may need a different fit than a person with a lighter complexion.
The type of laser being used; it goes without saying that each laser device has its own configuration and cannot be moved from one device to another. This procedure uses intense rays of light to remove damaged layers of skin while reducing the appearance of fine lines and wrinkles, acne scars and age spots. The biggest risks of laser skin rejuvenation are burns, scarring, and infections. Once your skin heals, you can use oil-free makeup to minimize redness, which usually disappears in two to three months. In general, you should discuss whether laser rejuvenation is right for you by talking to your doctor before having the procedure done.
If you have very dark skin, some laser rejuvenation techniques may cause swelling or discoloration after treatment. People with active skin infections, certain medical conditions, or very dark skin tones may not be ideal candidates. Laser therapy is an excellent method for rejuvenating skin texture and minimizing acne scarring. Both ablative and non-ablative laser rejuvenation methods can be performed with a fractioned laser, which creates microscopic columns of treated tissue.
Laser procedures carry an inherent risk of complications; however, a team approach that emphasizes patient education and care coordination will achieve the best results for patients. If aging, acne or excessive sun exposure have left your face with blemishes, scars, wrinkles or lines, laser skin rejuvenation can help your skin look younger and healthier. There may be an exception if you undergo the procedure to modify scars or remove precancerous skin growths. Today, there are many lasers available in the medical aesthetic industry, most of which are safe and effective when done by a trained technician.
Infection is one of the most common complications after laser treatments, especially ablative rejuvenation, because it alters the skin's barrier function. Laser applications in medicine continue to advance with the addition of new devices and the expansion of indications for laser therapy. Strictly avoiding sun exposure for two weeks before treatment can reduce the risk of post-inflammatory hyperpigmentation.
