The Effects of a 2-W Laser on the Nasolabial Fold of Ageing Individuals Investigated by High-Frequency Ultrasonography: A Nonrandomized Controlled Trial

Introduction: Biomechanical qualities of the skin tissue change following numerous pathological and natural (ageing) conditions. The best skin treatments are those resulting in a positive outcome with the fewest adverse effects. In this study, high-frequency ultrasonography (US), which provides a quantifiable scale, was utilized to evaluate the impact of a 2-W laser on characteristics of nasolabial fold (NLF) including depth and area, epidermis and dermis thicknesses, and Young’s modulus (YM). Methods: Nine female subjects (54.09±0.09 years old) with Fitzpatrick skin types III-IV and five young control participants (26±1.28 years old) for providing the control data were included in this study. Laser therapy was applied twice weekly for seven consecutive sessions. A class IV laser with 810-nm and 980-nm wavelengths, 2-W power, and 25-Hz frequency was applied twice a week for seven consecutive sessions. The energy administered had a density of 8 J/cm2 . An evaluation using high-frequency ultrasound (40 MHz) was accomplished before and 48 hours after the final treatment session. The Face-Q questionnaire was used to assess the patient’s perspective on this procedure. Results: For each US parameter, the intraclass correlation coefficient was high (ICC>0.9). After the laser treatment, NLF depth, area, epidermis, dermis, YM, and Face-Q significantly improved compared to baseline (P