RESUMO
BACKGROUND AND OBJECTIVES: Combined sequential treatments with multiple modalities such as lasers and soft-tissue fillers are commonly required for the treatment of atrophic acne scars. Recently, fractional treatment with picosecond-domain lasers has proven to be effective for skin rejuvenation and scar treatment. However, little is known about the effects of picosecond-domain fractional laser treatment over hyaluronic acid fillers (HAFs). We aimed to evaluate the in vivo tissue responses to 1064 nm picosecond-domain fractional neodymium:yttrium-aluminum-garnet (Nd:YAG) laser treatments using microlens array (MLA) applied over pre-injected HAF in rats. In addition, we evaluated the efficacy and safety of this combined same-day treatment for atrophic acne scars in patients. STUDY DESIGN/MATERIALS AND METHODS: Sprague-Dawley rats were subjected to 1064 nm picosecond-domain fractional Nd:YAG laser treatment immediately after HAF dermal injection. Skin specimens were histologically evaluated on days 0, 7, and 21. In a clinical study, 36 patients with acne scars were treated concurrently with 1064 nm MLA-type picosecond lasers and HAFs. The patients were scheduled to receive two consecutive treatments at 4-week intervals, with a follow-up visit at 12 weeks after the final treatment. Acne scar photographs were graded using the Goodman and Baron's qualitative and quantitative scales at baseline and 12 weeks post-procedure. RESULTS: Picosecond-domain fractional laser treatment immediately after the dermal injection of HAF into rats did not cause any histological changes in the filler or surrounding skin. In a clinical study, treated subjects (n = 36) achieved significant improvement in acne scars and patient satisfaction. No serious adverse events were observed. CONCLUSIONS: Combined picosecond laser and HAF treatment were proven to be safe and effective based on in vivo and clinical study results. Facial rejuvenation and scar treatment using a picosecond-domain fractional laser may be performed immediately after HAF injection. Lasers Surg. Med. © 2020 Wiley Periodicals, Inc.