Thursday, March 30, 2023
HomeDermatologyErbium-YAG Cutaneous Laser Resurfacing

Erbium-YAG Cutaneous Laser Resurfacing


Throughout the last decade, cutaneous laser resurfacing has gained popularity among laser surgeons and the public alike. Based upon the principles of selective photothermolysis, resurfacing lasers selectively target water-containing tissue resulting in controlled tissue vaporization. Associated residual thermal injury in the dermis results in collagen shrinkage and remodeling. See the image below.

Before (Left) and after (right) upper and lower li

Before (Left) and after (right) upper and lower lip resurfacing with Erbium 2.94 laser. Courtesy of Meir Cohen, MD.

Lasers currently available for cutaneous resurfacing include a high-energy pulsed or scanned carbon dioxide laser, a short-pulsed erbium:yttrium-aluminum-garnet (Er:YAG),
and modulated (short-and-long-pulsed) Er:YAG systems. High-energy pulsed or scanned carbon dioxide laser skin resurfacing can achieve excellent clinical improvement of photodamage, rhytides, and atrophic scars. However, this resurfacing is associated with an extended reepithelialization period and, in some cases, prolonged erythema that may persist for several months. Of greater concern is the potential for delayed permanent hypopigmentation seen in as many as 20% of patients when multiple-pass carbon dioxide resurfacing is performed. The demand for less aggressive modalities for skin rejuvenation led to the development of the Er:YAG laser.

The 2,940-nm wavelength emitted by the Er:YAG laser is absorbed 12-18 times more efficiently by superficial (water-containing) cutaneous tissue than is the 10,600 nm wavelength of the carbon dioxide laser. With a pulse duration of 250 microseconds, a typical short-pulse Er:YAG laser ablates 5-20 µm of tissue per laser pass at a fluence of 5 J/cm2 with minimal residual thermal damage (compared with 20-60 µm of tissue ablation and up to 150 µm of residual thermal damage per pass with the carbon dioxide laser). The precise tissue ablation and small zone of residual thermal damage results in faster reepithelialization and an improved side effect profile.

Because of these advantages, many thought the short-pulsed Er:YAG laser would supersede the carbon dioxide laser as a superlative ablative modality. However, initial enthusiasm for the short-pulsed Er:YAG laser was tempered by poor intraoperative hemostasis and less impressive clinical improvement (reduced tissue tightening) when compared to traditional high-energy pulsed or scanned carbon dioxide laser resurfacing.

In an attempt to overcome the limitations of the short-pulsed Er:YAG laser, modulated (short-and-long-pulsed) Er:YAG systems were introduced to facilitate deeper ablation of tissue, improve hemostasis, and increase collagen remodeling. With the addition of significant coagulative properties, modulated Er:YAG systems combined precise control of ablation with the ability to induce dermal collagen formation by means of thermal injury.

The concept of fractional photothermolysis revolutionized cutaneous laser resurfacing when introduced by Manstein et al in 2004.
Using a nonablative, 1550-nm Er-doped fiber laser, full-thickness columns of thermal injury (termed microthermal treatment zones or MTZs) are created in a pixelated pattern just below the level of the stratum corneum, with the surrounding skin left intact. Because epidermal barrier function is intact, healing is rapid, without oozing or crusting. Patients typically require a series of treatments for the best response for a variety of conditions such as photodamage and atrophic scarring. However, with the deepest scars or rhytides, the amount of overall improvement may be marginal with this nonablative approach. A study has shown that multiple sessions are effective in facial rejuvenation, stimulating the formation of new collagen and resulting in better skin texture and finer wrinkles.

Most recently, ablative fractional resurfacing treatments with either a carbon dioxide or 2940-nm Er:YAG laser have demonstrated good clinical outcomes with significantly less recovery time and adverse effects compared with traditional ablative laser skin resurfacing.
Research is ongoing to determine the most effective treatment protocols for this exciting new technique.

- Advertisment -

Most Popular