Fractional resurfacing entails treatment of small areas of the skin, so-called microthermal treatment zones (MTZs), while sparing the remainder of the skin. This results in decreased adverse events and faster healing relative to traditional full-field resurfacing. Nonablative fractional resurfacing (NAFR), which allows even more rapid healing and less need for analgesia, is best for atrophic and mature scars. Ablative fractional resurfacing (AFR), in which the treated skin is fully vaporized, is more appropriate for improving hypertrophic scars and remains the mainstay for scar rehabilitation, including functional improvement of restrictive scars. Adverse events after fractional resurfacing are typically mild and include self-remitting erythema and edema. In selected cases, antibiotic or antiviral prophylaxis may be appropriate. The use of conservative settings can minimize the already low risk of postinflammatory hyperpigmentation or additional scarring.
Hypertrophic and restrictive scars occur when there is a disruption in the normal wound-healing process. Clinically, these scars can create a negative emotional and physical impact. Burn scars are particularly challenging, given that tissue damage can extend both far laterally and deep into the skin.1 Approximately 650,000 people sustain burns in the United States every year that require medical treatment.2 Around 22 million people currently live in the United States with disabilities from cutaneous burns.3
There are numerous treatment options that vary in their mechanism of action and in the degree to which they can improve the overall appearance and functionality of mature scars. These include intralesional 5-fluorouracil or corticosteroids, compression, dermabrasion, chemical peels, silicone gel sheeting, radiation, lasers, surgery, and interferon.1 More recently, laser therapy has been found to be helpful for improving the functional and cosmetic aspects of traumatic and burn scars. Various lasers have been used, including the pulsed dye laser (PDL) and fractional ablative lasers such as erbium:yttrium-aluminum-garnet (Er:YAG) and carbon dioxide (CO2). The latter 2 have been shown to improve the vascularity, pigmentation, and thickness of scars.4 Additionally, they may help improve atrophic scars and may also decrease tension to increase functionality.3 These improvements can lead to reduction in symptoms and a better clinical appearance.
BASIS OF FRACTIONAL LASER TREATMENT OF SCARS
Laser scar revision is based on the principle of controlled thermal injury to induce healing and remodeling in a specific area. The concept of fractional lasers originated many years ago but was formalized within the last decade.3 Since then, fractional laser technology has revolutionized the treatment of burn scars.4 Fractional lasers produce arrays of nonselective microscopic thermal damage zones (MTZs) throughout the epidermis and dermis2 (Fig. 10-1). Water absorption in the infrared wavelength causes tissue coagulation to occur, which permits increased depth of penetration while minimizing tissue injury.5 Deeper tissue penetration induces tissue contraction and tissue remodeling, including new collagen production. Histologic studies have shown that tissue remodeling continues ...