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Update on fractional laser technology.

42 AESTHETIC UPDATE Introduction Since the introduction of the first fractional thermolysis (FT) device in 2004, dermatologists have seen numerous FT technologies introduced into the marketplace, which has increased the armamentarium we have available for our patients to treat a variety of skin concerns. With so many devices now available with numerous claims of clinical success, deciding which FT device to use can be confusing. The author reviewed FT in 2007, and it is his hope that this update brings further clarification to this ever-exciting world of FT. It is crucial to state at the onset that all FT devices are not the same, and even though almost every laser company produces an FT device, research endeavors, presentations at major medical meetings, and, most importantly, scientific publications in peer-reviewed medical journals are needed for the legitimacy of FT devices. As clinicians, we should demand the science behind medical devices and not rely on the so-called “white” papers laser companies are eager to make available. Although the majority of laser company papers are sponsored clinical studies, those that have credence will have an institutional review board (IRB) approval for safety concerns and a peer-reviewed manuscript, which helps provide the legitimacy laser companies are so eager to achieve. During the late 1990s and early 2000s, the gold standard for the treatment of facial lines and wrinkles as well as acne and traumatic scars was, at least from a laser point of view, the carbon dioxide (CO2) laser system. This laser was used, by most, in a continuous beam mode and removed all of the epidermis and a portion of the dermis. In the resultant wound-healing cascade, fibroplasia and neocollagensesis were evident in the treated areas. Downtime with the CO2 laser typically lasted about one week or more, and depending on the device and the aggressiveness of the clinician utilizing the device, potential adverse effects became more widespread. These potential adverse effects included pain, edema, persistent erythema, infections, postinflammatory hyperpigmentation, and the most problematic of all, hypopigmentation following the ablative procedure, seen in some patients two years following the laser surgery. Incidence rates for this postlaser hypopigmentation have varied from single digits to as high as 20 percent. To counter these potential adverse events, the erbium:yttriumaluminum-garnet (Er:YAG) laser was introduced. It has a higher absorption coefficient for water and theoretically should not produce the same adverse events as the “more powerful” CO2 lasers. In truth, postlaser hypopigmentation with the Er:YAG lasers still can occur as well as other problems similar to those of the CO2 laser. Downtime still may be from 5 to 7 days depending on the power utilized. Due to these “problems,” ablative laser resurfacing fell out of favor among many laser surgeons. Patients then began receiving rejuvenation treatments with near-infrared nonablative lasers, but with only minimal effects (as most would argue), and intense pulsed light (IPL) devices, which worked well for the treatment of pigment and vascular changes found on the skin, but had only minimal effects on collagen and elastin, thereby not providing the same results as ablative laser resurfacing in treating wrinkles and scars. The near-infrared lasers included various 1319 to 1320nm lasers as well as laser systems in the 1450 and 1540nm range. The 532nm potassium titanyl phosphate (KTP) laser and the 585 to 595nm pulsed dye lasers (PDL) also received attention in the rejuvenation arena, although they are much better at vascular treatments than rejuvenation. A E S T H E T I C U P D A T E