Microneedling prior to Levulan PDT for the treatment of actinic keratoses: A split-face, blinded trial

Introduction: Photodynamic Therapy (PDT) with topical Levulan is an approved and efficacious method for treating actinic keratoses. This therapy depends on the ability of the Levulan (delta amino levulinic acid) to penetrate the stratum corneum and enter the cells of the epidermis. Microneedling is an increasing popular cosmetic therapy in which an array of tiny needles is used to make holes in the epidermis and presumably induce a wound healing cascade that leads to cosmetic improvement of the skin. We were interested to know if prior microneedling would enhance the penetration of topical Levulan and thus enhance the PDT treatment, and if a cosmetic improvement beyond the PDT alone would be seen when it is used in conjunction with microneedling. Methods: 20 patients each with at least 4 non hyperkeratotic AKs on each side of their face were enrolled. All patients were randomized to receive multiple passes with a microneedling device to 1/2 of their face, left or right, followed by application of Levulan to the entire face. The Levulan was allowed to incubate 1 hour followed by exposure to blue light (Blu U) for 1000 seconds. Results: 19 patients completed the study with 4-month follow up. The mean percentage reduction in AKs was 89.3% on the microneedling side versus 69.5% on the PDT alone side, a significant difference. A physician's global cosmetic assessment was performed based on Canfield Visia photographs: 15 of the 19 patients had a noticeable improved cosmetic appearance on one side of the face versus the other, and in 13 of these patients the improved side was the microneedled side. Discussion: Prior microneedling significantly enhances the effect of Levulan PDT. It also seems to provide a cosmetic benefit above and beyond the PDT alone. It was safe and well tolerated in this study.