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
