Artificial daylight
photodynamic therapy is a near-painless treatment for
actinic keratoses, which can be performed indoors using a controlled light dose. Daylight
photodynamic therapy is approved only for treatment of grade I-II
actinic keratoses. The aim of this study was to evaluate whether fractional
laser pre-treatment improves the outcomes of daylight
photodynamic therapy for
actinic keratoses of all grades. In addition, the study compared the outcomes of artificial and natural daylight
photodynamic therapy. This randomized single-blinded split-side comparative study included 60 patients with ≥ 2
actinic keratoses of the head. Fractional
laser pre-treatment was assigned randomly for
actinic keratoses on 1 side of the head and, subsequently, the entire treatment area was treated with artificial or natural daylight
photodynamic therapy. Fractional
laser-mediated daylight
photodynamic therapy achieved significantly higher complete clearance (50.0% vs 30.3%, p = 0.04), partial clearance (78.6% vs 50.0%, p < 0.01) and lesion-specific clearance (86.2% vs 70.2%, p < 0.01) than daylight
photodynamic therapy alone at the 6-month follow-up. No significant differences were found in the outcomes of artificial vs natural daylight
photodynamic therapy or grade I lesions vs grade II-III lesions. Thus, fractional
laser pre-treatment appears to significantly increase the efficacy of artificial and natural daylight
photodynamic therapy, and to be suitable for treatment of
actinic keratoses of all grades.