Characterization of picosecond laser-induced optical breakdown using harmonic generation microscopy.
Connie Liu1,2, Pei-Jhe Wu3,4, Shih-Hsuan Chia1
1Institute of Biophotonics, National Yang Ming Chiao Tung University, Taipei, Taiwan.
Lasers in Surgery and Medicine
|April 13, 2023
Summary
Fractional picosecond Nd:YAG laser treatment creates epidermal vacuoles and alters collagen, potentially driving dermal remodeling and neocollagenesis for skin rejuvenation.
Area of Science:
- Dermatology
- Laser Physics
- Histopathology
Background:
- Fractional picosecond 1064-nm Nd:YAG lasers are used for facial rejuvenation.
- The mechanism of dermal remodeling from this nonablative treatment is not fully understood.
Observation:
- Histopathological analysis and in vivo harmonic generation microscopy (HGM) were used.
- The study examined laser-induced changes in human skin phototypes III-IV.
- HGM visualized collagen (SHG) and epidermal components (THG).
Findings:
- Microscopic examination revealed epidermal vacuoles and keratinocyte degeneration.
- HGM showed laser-induced shock wave propagation and loss of collagen signals in the papillary dermis.
- The fractional picosecond laser treatment induced epidermal vacuoles and collagen alterations.
Implications:
- These collagen changes suggest a mechanism for dermal remodeling and neocollagenesis.
- Understanding these mechanisms can optimize fractional picosecond laser treatments.
- This research provides insight into the nonablative effects of picosecond lasers on skin.
