Light-Emitting Diode–Based Photodynamic Therapy for Photoaging, Scars, and Dyspigmentation: A Systematic Review

BACKGROUND Light-emitting diodes (LEDs) may be used as an activating light source for photosensitizers in photodynamic therapy (PDT), a form of noninvasive phototherapy. Photodynamic therapy for aesthetic dermatologic conditions has demonstrated skin rejuvenating effects. OBJECTIVE To evaluate the safety and efficacy of PDT using LEDs to treat aesthetic dermatologic conditions including photoaged skin, scarring, and dyspigmentation. MATERIALS AND METHODS A search of PubMed and EMBASE databases was conducted through May 31, 2019, to identify studies that used LEDs as a light source for PDT and evaluated cosmetic improvements as the primary outcome measure. RESULTS A total of 24 original articles were included in the authors' systematic review. The available evidence supports methyl aminolevulinate or 5-aminolevulinic acid incubation followed by LED treatment for global improvement of skin quality, including smoother texture, reduction of rhytides, and improvement of scars. Histologic analysis for global skin improvement demonstrated increased collagen fibers and decreased elastin fibers after LED-mediated PDT. CONCLUSION Light-emitting diode–based PDT seems to have beneficial effects for photoaging, scars and dyspigmentation. A paucity of high-quality studies using LED-based PDT for aesthetic outcomes was found, highlighting the need for well-designed randomized control trials on this topic.