Effect of Subdermal 1,444-nm Pulsed Neodymium-Doped Yttrium Aluminum Garnet Laser on the Nasolabial Folds and Cheek Laxity

Abstract

BACKGROUND: Wrinkle formation usually accompanies skin aging. In particular, accentuated nasolabial folds and loss of elasticity are early signs of skin aging. The use of 1,444-nm pulsed neodymium-doped yttrium aluminum garnet (Nd:YAG) lasers has increased in popularity. OBJECTIVE: To evaluate the safety and efficacy of a novel 1,444-nm pulsed Nd:YAG laser in the treatment of NLF and cheek laxity using subdermal laser therapy. METHODS: Ten Korean patients with moderate to severe NLF were enrolled. Each received a single treatment session with a 1,444-nm Nd:YAG laser. Two blinded physicians evaluated clinical improvement by rating comparative photographs on a 5-point scale. Efficacy was also assessed by measuring elasticity and roughness. Skin biopsies were performed on five volunteers before treatment and 3 months after treatment. RESULTS: The 1,444-nm Nd:YAG laser effectively promoted clinical improvement of NLF and cheek laxity (p < .05). Significant differences in elasticity and roughness were observed (p < .05). Epidermal proliferation was stimulated as demonstrated by increases in epidermal thickness and Ki-67 expression (p < .05). Quantitative image analyses of pre- and post-treatment biopsies revealed that collagen fibers increased from baseline (p > .05). Transforming growth factor beta and heat shock protein-70 messenger RNA levels quantified using real-time reverse transcriptase polymerase chain reaction increased significantly from baseline (p < .05). CONCLUSION: The 1,444-nm Nd:YAG laser is an effective treatment modality with minimal complications for the treatment of NLF and cheek laxity, but further research with a larger group of patients is needed to confirm these findings.