Comparison of Heat Shock Protein 70 Expression in Response to Different Non-Ablative Lasers: An In Vitro Study

Dynamic panoramic presentation of skin function after fractional CO2 laser treatment

Fractional CO2 laser, as a typical ablative laser, has been used to assist in the treatment of many skin diseases, such as photoaging, atrophic scar, hypertrophic scar, superficial pigmentation, vitiligo, and so on. However, the dynamic changes in skin function after fractional CO2 laser treatment are still unclear. This study explored the changes in local skin function and possible regulatory mechanisms after fractional CO2 laser treatment for 1, 3, 5, and 7 days through transcriptome high-throughput sequencing. The results showed that fractional CO2 laser tended to transform the "lesions" into "normal skin", regulate the skin barrier, coordinate the rearrangement of collagen, enhance the local microvascular circulation, activate the immune system to secrete a large number of cytokines, and act as an auxiliary tool to assist drug transport. In conclusion, according to the basic principle of destruction before reconstruction, fractional CO2 laser plays a key role of balancer in skin reconstruction.

Review of Lasers and Energy-Based Devices for Skin Rejuvenation and Scar Treatment With Histologic Correlations

BACKGROUND

Lasers and energy-based devices (EBD) are popular treatments for skin rejuvenation and resurfacing. Achieving desired outcomes and avoiding complications require understanding the effects of these devices at a histologic level. Currently, no comprehensive review summarizing the histologic effects of laser and energy-based treatments exists.

OBJECTIVE

To describe how lasers and EBD alter skin histology and improve the overall understanding of these devices.

MATERIALS AND METHODS

A PubMed search was conducted for studies with histologic analysis of fractional picosecond laser, fractional radiofrequency microneedling, nonablative lasers, and ablative lasers.

RESULTS

Fractional picosecond lasers induce intraepidermal and/or dermal vacuoles from laser-induced optical breakdown. Fractional radiofrequency microneedling delivers thermal energy to the dermis while sparing the epidermis, making it safer for patients with darker skin phototypes. Fractional nonablative lasers induce conical zones of coagulation of the epidermis and upper dermis. Ablative lasers vaporize the stratum corneum down to the dermis. Traditional ablative lasers cause diffuse vaporization while fractional ablative lasers generate columns of tissue ablation.

CONCLUSION

Lasers and EBD are effective for skin resurfacing and rejuvenation and have different mechanisms with disparate targets in the skin. Safe and effective use of devices requires understanding the histologic laser-tissue interaction.