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

Abstract

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. 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. 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 3months after treatment. 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). 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.