Background and Design: Topical photodynamic treatment (PDT) with endogenous porphyrine consists of irradiation of a lesion with visible light after the local application of exogenous 5-aminolevulinic acid (ALA). In this study, the effectiveness and usefulness of the photodynamic treatment in solar keratosis were investigated. Materials and Methods: A total of 20 patients with 25 lesions (19 at the face, 4 on the scalp and 2 at the hands) received photodynamic treatment combined with 5-aminolevulinic acid (occlusive application of a 20% ALA emulsion for 6-8 h, irradiation with red light, 580-720 nm). Histological and clinical evaluation were performed both before treatment and 2 months after treatment. Results: In clinical evaluation, complete response was achieved in 84% of lesions. 64% of the histologic specimens showed complete improvement rate. No notable side effects were observed. Conclusion: Photodynamic treatment combined with ALA is an effective model in the treatment of solar keratosis. The potential advantages of PDT over conventional modalities include its non-invasiveness, the ability to treat multiple lesions at one sitting, the good patient acceptance and excellent cosmetic results
