Clinical and histologic changes after 755-nm picosecond laser with a novel platinum focus lens array in the treatment of photo-aged skin.

The 755-nm picosecond laser device has undergone recent updates. A comprehensive evaluation is warranted to summarize and recognize efficacy and safety profiles of the 755-nm picosecond laser with a novel platinum focus lens array for skin lightening and rejuvenation. A retrospective analysis was conducted on patients who received treatment with the updated 755-nm picosecond laser device. Standardized clinical photographs were taken prior to treatment and during follow-up assessments. A modified global aesthetic improvement scale was employed as the main evaluation indicator. Additionally, the abdomens of 4-week-old Bama miniature pigs were treated with the new laser device. Histological changes were examined using hematoxylin and eosin staining, Masson's Trichrome staining, and immunohistochemical techniques. The study involved 10 patients with Fitzpatrick skin types IV to V, presenting with wrinkles, enlarged pores, and pigmented lesions. Notable improvements were observed, accompanied by minimal downtime and complications. Histological analysis conducted immediately after treatment revealed the presence of vacuoles within the epidermis and extravasation of red blood cells in the superficial dermis. Furthermore, dermal thickness exhibited a significant increase following treatment across all energy settings. The expression of collagen type I proteins also showed an increase post-treatment with the new device. The newly developed 755-nm picosecond laser device effectively induces laser-induced optical breakdown and initiates dermal remodeling. It represents a safe and effective therapeutic option for facial rejuvenation.