Resurfacing

Abstract

One of the most popular treatments for rejuvenation of aging skin is resurfacing. Skin resurfacing removes the outer layers of photodamaged skin with subsequent re- epithelization and neocollagenosis. Resurfacing procedures create a controlled injury to the skin to a desired depth to stimulate new epidermis and dermis with improved skin characteristics. Of all of the possible procedures for resurfacing, lasers offer the most precision. Ablative resurfacing with carbon dioxide (CO2) is considered the gold standard for laser resurfacing (Lask et al., Dermatol Surg 21(12):1021-1024, 1995). CO2 lasers emit light at 10,600nm and are either continuous (CW) or pulsed. The degree of thermal damage is dependent on laser wavelength, irradiance and duration of laser exposure. Continuous wave CO2 lasers have a myriad of adverse effects. In the 1980s, researchers created short pulsed CO2 lasers. By using pulse durations shorter than the thermal relaxation time, thermal damage zones were reduced and thus improved the safety profile (Shim et al., Dermatol Surg 24(1):113-117, 1998). Next, pulsed ablative CO2 lasers were created giving more control of tissue vaporization, decreased thermal damage and improved hemostasis (Dover and Hruza, Semin Cutan Med Surg 15(3):177-188, 1996; Lowe et al., Dermatol Surg 21(12):1025-1029, 1995). The 2,940 nm Er:YAG device was then developed to reduce adverse effects associated with CO2 laser. The Er:YAG is absorbed 16 times more strongly by water than the CO2 laser. Er:YAG ablation is more precise with less thermal damage than the CO2 laser. Thus Er:YAG resurfacing efficacy increases with increasing depth of ablation (via multiple passes) and increased thermal damage (Ross et al., Lasers Surg Med 30:93-100, 2002) Although extremely effective for repairing aging skin the adverse events of traditional ablative laser including long post-operative recovery times, significant pigmentary changes and often prolonged erythema caused physicians to search for new options. In the 1990s non-ablative resurfacing emerged with vascular lasers, mid infrared lasers and Q-switched asers which had modest collagen remodeling with minimal clinical efficacy. To address the adverse sequelae of ablative resurfacing and limited efficacy of nonablative laser the concept of fractional photothermolysis was developed (Manstein et al., Lasers Surg Med 34:426-438, 2004). In fractional photothermolysis scanners create array of microscopic wounds at deep dermal depths with controlled collateral coagulation. These microscopic wounds result in zones surrounded by normal tissue which allow for rapid healing of the laser treated columns. Fractional laser wounds can be tuned to specific depths with controlled collateral thermal damage. The first fractional device was the nonablative 1550 nm erbium glass laser. Patients needed multiple nonablative treatments monthly to achieve significant clinical results. Next was the development of fractional ablative CO2 and Er:YAG devices with impressive histologic and clinical effects (Reilly et al., Arch Facial Plastic Surg 12:321-325, 2010). Non-ablative fractional resurfacing (NAFR) results are less robust, but have minimal downtime whereas ablative fractional resurfacing (AFR) and traditional resurfacing have variable degrees of downtime, but greater efficacy. Adverse events appear highest with traditional resurfacing (Tanzi and Alster, Plast Reconstr Surg 111(4):1524-1529, 2003). Now with a greater understanding of the pros and cons of all resurfacing modalities we are experiencing a laser resurfacing renaissance. Laser physicians are now combining modalities such as traditional resurfacing to difficult rhytides (periorally) and treating the rest of the face with fractional lasers. Fractional lasers are emerging as an important modality in the treatment of scars (Reilly et al., Arch Facial Plastic Surg 12:321-325, 2010; Tanzi and Alster, Plast Reconstr Surg 111(4):1524-1529, 2003; Waibel and Beer, J Drugs Dermatol 7(1):59-61, 2008; Tierney et al. Dermatol Surg 35(8):1172-1180, 2009). Individualized skin rejuvenation for patients include fully ablative, fractional ablative, non-ablative fractional lasers with injectables and surgical interventions or any combination of these techniques.