Objective To investigate the feasibility of human amniotic membrane-living skin equivalent (AM-LSE) in repairing the skin defect. Methods A 5-year-old boy with giant nevus at neck, shoulder, and back was admitted in July 2016. Normal skin tissue of the patient was harvested and keratinocytes and dermal fibroblasts were separated and expanded in vitro. Human AM was donated from a normal delivery and de-epithelialized for constructing an LSE as a matrix. Keratinocytes were seeded on the epithelial side of the AM which was previously seeded with fibroblasts on the stromal side and then the complex was lifted for air-liquid surface cultivation for 10 days and observed under naked eyes and sampled for histological study. The nevus was excised to deep fascia and the skin defect in size of 20 cm×15 cm was covered with artificial skin of collagen sponge for 2 weeks to enhance granulation tissue formation, and then the AM-LSE grafts of stamp size were grafted on. The dressing was changed until the wound healed. Results After 10 days of air-liquid surface cultivation, the AM-LSE developed a multilayered and differentiated epidermis with the fibroblasts-populated amnion as the dermal matrix. The LSE stamps survived and expanded to cover the whole wound. The grafted area showed normal skin color and soft contexture at 6 months after operation, and histological study showed well developed epidermis with compactly aligned basal cells, stratified and well differentiated squamous, granular layers and stratum corneum and well vascularized dermal compartment without inflammatory cells infiltration. Conclusion The cultivated AM-LSE with autologous cells can repair skin defect and survive for a long term without rejection.
Nevus flammeus is a skin disease caused by congenital skin capillary malformation. In recent years, photodynamic therapy (PDT) has been proved to be effective and safe for this disease, but significant pain in the treatment process is the biggest obstacle to the implementation of this therapy. This article reviews the current pain management strategies in PDT. The current pain management methods include topical anesthesia, cold air analgesia, nerve block and others. Topical anesthesia has weak analgesic effect and short duration in PDT. Cold air analgesia is simple and feasible, but there is potential risk of affecting the treatment effect. The analgesic effect of nerve block is accurate, but the application scenario is limited. For nevus flammeus patients who need PDT, individualized analgesia should be selected according to the patient’s age and treatment scenario.