Balancing safety and efficacy in photodynamic therapy for facial port-wine stains in children aged 2-7 years: a prospective controlled study of light-intensity optimization

Background Hemoporfin-mediated photodynamic therapy is increasingly used to treat port-wine stains (PWS), but evidence regarding appropriate light intensity for young children remains limited.Objective To compare safety and efficacy of two light-intensity regimens for hemoporfin-mediated photodynamic therapy in 2- to 7-year-old children with facial PWS.Methods In this open-label prospective controlled study, 40 children were enrolled sequentially to receive photodynamic therapy using light intensities of 60 or 75 mW/cm2 with a hemoporfin dose of 5 mg/kg. The primary outcome was the overall effective rate at 8 weeks after treatment. Clinical outcomes were evaluated at 8 and 24 weeks. The trial was registered at ClinicalTrials.gov (NCT04106258).Results Both treatment regimens were well tolerated and achieved similar overall effective rates at 8 and 24 weeks. The higher light-intensity regimen was associated with a higher complete clearance rate at 24 weeks but also a significantly higher incidence of post-inflammatory hyperpigmentation. No serious adverse events were observed.Conclusion Both light-intensity regimens improved facial PWS in children aged 2–7 years. In this exploratory, non-randomized comparison, 75 mW/cm2 was associated with a higher observed complete-clearance rate, but an increased risk of post-inflammatory hyperpigmentation. Lower light intensity may be considered when minimizing post-inflammatory hyperpigmentation is a clinical priority.