Laser resurfacing is a very popular procedure worldwide. Full field and fractional lasers are used in many aesthetic practices. There have been significant advances in laser resurfacing in the past few years, which make patient treatments more efficacious and with less downtime. Erbium and carbon dioxide and ablative, nonablative, and hybrid fractional lasers are all extremely effective and popular tools that have a place in plastic surgery and dermatology offices.
Key points
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Full field means 100% of the treated area is removed to the selected depth.
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Fractional means discontinuous portions of the treated area are removed.
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Recovery time is linked to the amount of damage created.
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Fractional treatments usually have less downtime than full field treatments.
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Complications can arise with all of these laser treatments.
Introduction
Data from The American Society of Aesthetic Plastic Surgery collected yearly from core specialists since 1997 through 2014 have shown the increase, decrease, and increase again of laser resurfacing. In 2014 more than 583,000 full field and fractional laser resurfacings were performed in core offices making this the fourth most popular procedure overall after botulinum toxins, hyaluronic acid fillers, and laser hair removal.
Introduction
Data from The American Society of Aesthetic Plastic Surgery collected yearly from core specialists since 1997 through 2014 have shown the increase, decrease, and increase again of laser resurfacing. In 2014 more than 583,000 full field and fractional laser resurfacings were performed in core offices making this the fourth most popular procedure overall after botulinum toxins, hyaluronic acid fillers, and laser hair removal.
History
Full Field Resurfacing
The introduction of carbon dioxide lasers for skin resurfacing in the mid 1990s started the era of laser resurfacing. Lasers quickly replaced chemical peels and dermabrasion in many offices. These devices are used for full field resurfacing, which means that 100% of the target area from the epidermis down is treated ( Fig. 1 A ). Continuous mode carbon dioxide lasers (10,600 nm) were initially used, but complications due to excessive depths of ablation and thermal damage led to discontinuous or pulsed systems. The water chromophore of the carbon dioxide laser allowed tissue vaporization and left behind in the tissues some resultant thermal injury. The initial discontinuous systems delivered either short pulses (Ultrapulse laser, Lumenis lasers, Yokneam, Israel) or scanned pulses (Silk-touch and Feather-touch lasers, Lumenis lasers, Yokneam, Israel). Both methods created a short exposure time to ablate tissue (approximately 75–100 μm) and limited the thermal damage (approximately 75–100 μm) that was created with the continuous systems. Spectacular results of eradicating wrinkles and tightening lax tissue were excellent in many patients, but as long-term experience was obtained there was noted to be an unacceptably high hypopigmentation rate. The pigmentary complications, scarring in some patients, and the considerable patient healing period led to the demise of full field carbon dioxide laser resurfacing around the turn of the century.
Erbium:YAG lasers (2940 nm) have a higher water absorption coefficient than carbon dioxide lasers (about 10 times more efficient) and ablate tissue with much less thermal damage (5–10 μm). These lasers were introduced around the end of the carbon dioxide full field era and were initially marketed for superficial resurfacing as the initial machines were low powered and it was difficult to achieve deeper depths of ablation. Subsequent systems had more significant power and had pattern generators similar to the more advanced carbon dioxide systems. Complications seemed to be less than with carbon dioxide systems, although comparative studies showed recovery time and results to be determined by depth of injury rather then the laser used. Combination systems of carbon dioxide and erbium lasers were also used (Derma-K, Lumenis lasers, Yokneam, Israel).
The authors’ favorite full field laser is the Sciton variable pulse width erbium laser (Sciton Inc, Palo Alto, CA). This device blends the best concepts of the carbon dioxide lasers with the best of the erbium lasers by having a very-high-power erbium laser and by allowing variation of the erbium pulse width, which controls the amount of residual thermal injury. This system creates very precise ablation and where needed/wanted controlled thermal damage (less then with carbon dioxide systems). The clinical results are excellent with a much shorter period of erythema and much lower risk of hypopigmentation ( Figs. 2–4 ).
Other wavelengths for skin resurfacing have been introduced (2780 nm and 2790 nm) (Cutera Lasers, Cutera, Brisbane, CA; Palomar Lasers, Cynosure Inc, Westford, MA) but have not had significant commercial success.
Fractional Resurfacing
Fractional lasers create an array of injury and treat a fraction of the skin at any one time leaving intact skin bridges adjacent to the treated area (see Fig. 1 B). This method differs from full field resurfacing in which 100% of the skin surface treated is removed. Manstein and colleagues introduced this concept in 2004. The first generation of these devices was nonablative and created a zone of desiccated tissue called a microthermal zone (MTZ) ( Fig. 5 ). The first of these devices was at 1550 nm (Reliant technologies, Mountain View, CA, now Solta Medical part of Valeant Pharmaceuticals International). Currently other nonablative wavelengths are also used (1440 nm, 1470 nm, 1540 nm). After an MTZ was created, healing occurred from deeper structures as well as from adjacent structures. This method differs from full field resurfacing in which healing occurred from only deeper structures, that is, hair follicles and sebaceous glands. Deeper treatments and body treatments can safely be performed with nonablative fractional lasers. After the injury was created, the epidermal basal layer was restored within 24 hours and the skin expelled the MTZ over the next week. The expelled MTZ containing melanin was called the microscopic epidermal necrotic debris. New collagen was created and the skin rejuvenated. Advantages of nonablative fractional resurfacing were avoidance of an open wound and very low risk of complications, including pigment disturbance or scarring. Disadvantages include the need for multiple treatments and somewhat less clinical response than with full field ablative resurfacing.
The next advance in laser resurfacing was the development of fractional ablative resurfacing ( Fig. 1 C). These lasers in wavelengths of carbon dioxide, erbium, and YSGG systems created a column of tissue ablation in the skin instead of a column of desiccated tissue like the fractional nonablative systems (see Fig. 5 ). The varying fractional ablative devices differ not only in wavelength but also in system power, spot size, and amount of thermal damage created adjacent to and deep to the ablated hole. Carbon dioxide ablative fractional lasers ablate tissue and leave a ring of adjacent thermal tissue. The erbium lasers leave less thermal damage but with usually more bleeding. The Sciton ProFractional erbium fractional laser allows one to vary the amount of thermal damage similarly to their full field system ( Fig. 6 ). Other newer carbon dioxide fractional lasers allow variation of the thermal damage zones (Deka Medical, San Francisco, CA), whereas others allow superficial and deeper penetration with a single scan (Syneron, Yokneam, Israel). These ablative fractional lasers are more efficacious then the nonablative fractional lasers but create more patient healing time albeit much less then the full field ablative variants. Experiments with both ablative and nonablative fractional lasers in same session treatment proved promising.
The Thulium device (1927 nm) by Solta Medical is a nonablative fractional device marketed as especially effective in removing superficial pigment. This device is generally used with their nonablative 1550-nm laser.
The newest fractional laser on the market is a hybrid fractional laser made by Sciton (Palo Alto, CA) and called the Halo. This device is very interesting as it allows coincident delivery of first their erbium fractional laser then a nonablative 1440-nm pulse in the same hole. This device is very efficacious and creates very minimal healing times. This laser is the authors’ laser choice for skin rejuvenation when recovery time is limited ( Figs. 6 and 7 ).
