Objectives: Daylight-PDT (DL-PDT) is a soft and progressive, painless, mode of PpIX activation as it is produced (30 min of incubation of topical ALA or MAL, 2h continuous exposure). The clinical adventure of DL use for PDT began in the early 20th century but this technique was forgotten until Pr Wulf et al revived it. The first proof of concept study on the efficacy to treat actinic keratoses of the face and scalp was published in 2008. Its non-inferiority has now been proven in numerous multicenter randomized clinical trials. Photorejuvenation (PR) and acne are possible off-label cosmetic uses of PDT
Introduction: PR-PDT ( based on clinical, histological and, with immunohistochemical markers assessment, studies) can both normalize UV-induced atypical keratinocytes and markers (decrease of baseline epidermal p53 level ...) and induce a dermal reshaping by direct effect on dermal FB (ERK signaling pathway ) and indirect epithelial- mesenchymal interactions (IL, TNF, MMPs, ARNm coll…) even for low-level PDT (6J/cm²). Clinical results, even with daylight use, show that tone, lentigos, skin roughness, texture and fine wrinkles can be improved.
Materials / method: Protocols of prior microporation -microneedling, sandpaper abrasion or fractional laser) of the treated skin before ALA or MAL application (assisted delivery – ‘’intensified’’ PDT) are used to enhance PpIX formation and efficiency of PDT sessions but with severe pain rated from 6 to 8 on 10 visual analogic scales. These scores are not acceptable for rejuvenation techniques. The combination of ALA or MAL-assisted delivery and daylight exposure offers a dual benefit: increased efficiency and very low pain scores (0-1 on VAS). It can also be used on extrafacial areas such as the decolletage.
Results: For acne, PDT is always a 2nd or 3rd line of treatment. In the last Cochrane review, among all light therapies, only red-LED MAL-PDT has demonstrated a low-to moderate evidence of efficacy. Applied this way it can be efficient on inflammatory and non inflammatory lesions but adverse effects range from severe to unbearable (intense pain during illumination, volcanic eruption and social eviction of up to 8-10 days, prolonged risks of erythema or post-inflammatory hyperpigmentation…). Daylight use could be an alternative but there is no reference in the literature except for 1 recent Korean study
Conclusion: reporting the absence of significant effect in non inflammatory lesions (Tae In Kim et al., 2017). In the future it could interesting to use creams containing photosensitizers at low dosage and daily...daylight use ! (as it has been published by Kwon et al in 2016 J dermatol.)
Declaraciones
¿Ha recibido algún tipo de financiamiento para realizar su investigación sobre esta temática?
No
¿Ha recibido algún pago, honorario u otra compensación por su trabajo acerca de esta investigación?
No
¿Tiene vínculos financieros con alguna entidad que podría llegar a competir estrechamente con los medicamentos, materiales o instrumentos tratados en su investigación?
No
¿Posee o ha solicitado una patente relacionada a los materiales, productos o instrumentos utilizados en su investigación?
No
Este trabajo no cuenta con el apoyo de ningún financiamiento directo o indirecto. El autor asume plena responsabilidad sobre el mismo.
