A Prospective Split-Face Study of the Picosecond Alexandrite Laser With Specialized Lens Array for Facial Photoaging in Chinese

November 2016 | Volume 15 | Issue 11 | Original Article | 1390 | Copyright © November 2016


Yiping Ge MD, Lifang Guo MD, Qiuju Wu MD, Mengli Zhang MD, Rong Zeng MD, and Tong Lin MD PhD

Department of Cosmetic Laser Surgery, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, P.R., China

Abstract
Background: A 755nm picosecond alexandrite laser with a diffractive lens array has been reported for the treatment of acne scar and photoaging with clinical ef cacy. In this study, we evaluated the application of the 755nm picosecond alexandrite laser with a diffractive lens array for facial photoaging in Chinese. Materials and Methods: Ten subjects with moderate facial photoaging were enrolled in a prospective, evaluator-blinded, open-label, and split-face trial to assess the ef cacy and safety of the 755nm picosecond alexandrite laser with a diffractive lens array for facial photoaging. Each subject received a series of four treatment sessions on the right side of the face at two-week intervals. The left side of the face served as the control side. Blinded evaluation of baseline, pre-treatment, and two-month follow-up visit was performed by two independent dermatologists on a 5-point global photoaging scale (GPS) and a 6/8-point Asian photographic scale (APS). Adverse events and discomfort associated with the treatment were also assessed. Results: Signi cant improvement in photoaged tissue was observed on the treated side of the face, with a mean GPS score decrease from 2.67 to 1.44 at the two-month follow-up visit. A greater improvement in wrinkles was observed (2.78 vs 1.89; P less than 0.05) when com- pared to the improvement in pigmentation (2.67 vs 2.11; P less than 0.05). No changes were observed on the control side. Treatment results improved gradually throughout the treatment program and continued to the two-month follow up. In addition, skin tightening was perceived in all subjects, and shallower nasolabial folds were observed in 60% of the subjects on the treated side of face. Moderate pain and transient erythema were observed as the two main discomforts associated with the treatment. Conclusions: The 755nm picosecond alexandrite laser with a diffractive lens array is efficacious and safe for rejuvenation of photodamaged facial tissue in Chinese. J Drugs Dermatol. 2016;15(11):1390-1396.

INTRODUCTION

Photoaging is a major cosmetic concern which is characterized by various cutaneous changes on sun-exposed areas induced by excessive or cumulative ultraviolet radiation.1 These changes include irregular pigmentation, fine lines, wrinkles, keratosis, coarse skin texture, and skin tone alterations. Various treatment modalities have been introduced to address photoaging, such as lasers, chemical peels, radiofrequency, ultrasound, injections, and surgery.2 Many of these invasive approaches, especially ablative lasers and surgery, are associated with an extended downtime and an increased risk of complications including dyspigmentation, skin infections and scarring. Darker skin type populations are more prone to develop post-inflammatory hyperpigmentation (PIH), limiting the use of those invasive procedures despite their enhanced clinical efficacy.3 Asians have been particularly problematic with PIH as a result of unpredictable responses to laser due to undiagnosed melanin content. As a result, non-invasive or minimally invasive approaches, such as fractional and non-ablative lasers, have been gaining in popularity due to their clinical benefit with a low occurrence of side effects.4-6Q-switched laser technology has been widely used for the treatment of unwanted tattoos and benign pigmentary skin disorders.7 In recent years, Q-switched Nd:YAG Laser (QSNYL) toning, a noninvasive approach, has also been shown to successfully improve photoaging and acne scarring with a little or no downtime and minimal side effects.8,9 A new generation of technology, a picosecond-pulsed alexandrite laser (755nm), has recently been introduced for its superior effectiveness in the treatment of unwanted tattoos and various unwanted pigmentary conditions.10-13 Because of its extremely short pulse duration (hundreds of picoseconds), this novel alexandrite laser is capable of generating both photothermal and photomechanical effects on the tissue while minimizing collateral thermal damage. Combining a specialized diffractive lens array, the picosecond laser delivers intensified energy in a fractionated manner while maintaining a low total fluence, hence achieving a high safety profile. This novel non-ablative fractional resurfacing technology has been reported to be effective for acne scarring and photoaging décolletage.14,15 This new technology has also added a new component to traditional Q-switched