What's New and Hot with PDT Therapy WCH25
Featuring Dawn Merritt, DO |
Dermatology Residency Program Director
OhioHealth Riverside Hospital
Columbus, OH
Photodynamic therapy (PDT) is an important tool in dermatologists’ toolbox for actinic keratosis treatment and reduction of nonmelanoma skin cancer risk. Unfortunately, PDT has a bad reputation with patients for being too painful and time consuming. In this high-yield session, Dawn Merritt, DO, discussed practical tips for incorporating PDT into your practice. Dr Merritt briefly reviewed the mechanism of action of PDT before discussing the most common photosensitizers and light sources used in the office. Aminolevulinic acid (ALA) 20% solution and ALA 10% gel are the two photosensitizers available in the United States, with ALA 20% solution approved for blue light use and ALA 10% gel approved for red light use.
Dr Merritt discussed the classic protocol for performing PDT, which includes debridement of lesions, application of the photosensitizer, incubation with or without occlusion, and illumination. Recently, studies have emerged that question the optimal photosensitizer, incubation period, and illumination time. A split-face and scalp study of ALA 10% gel versus ALA 20% solution with a one-hour incubation followed by 1000-second blue-light illumination found that both photosensitizers had similar rates of lesion clearance, while ALA 20% solution was associated with more local skin reactions such as erythema, crusting, and scaling.
Changes in incubation time have led to the development of “painless PDT” in recent years. Dr Merritt reviewed a small, split-face study of 23 patients comparing conventional blue light PDT with one-hour incubation and 1000-second illumination with no incubation and illumination for 30, 45, or 60 minutes. All patients who received immediate illumination experienced significantly less pain, and lesion clearance was similar between the two protocols. Dr Merritt cautioned that there is no consensus on which sensitizer, illumination source, or illumination time is preferred, but all studies have shown noninferiority with conventional PDT. Dr Merritt has performed this “painless PDT” with red light using a 30-minute illumination time and seen good lesion clearance with low rate of adverse events. Dr Merritt does recommend using occlusion for PDT on the upper extremities for higher efficacy. To conclude, Dr Merritt discussed case studies of newer uses for PDT including acne vulgaris, photorejuvenation, and folliculitis decalvans.
More from this series
Psoriasis
60 Tips in 60 Minutes - Day 1: Psoriasis, Urticaria, Infection, Skin Cancer, HS and Office Management
Featuring Clay Cockerell, MD | Cheri Frey, MD | Mark Lebwohl, MD
Acne
So Many Topicals, So Little Time: Pearls on Selecting Among Acne Topical Therapies
Featuring Julie Harper, MD
Related CME



Related Media
Powered by Polaris TM
Actinic Keratoses
Efficiently Implementing Photodynamic Therapy (PDT) for Actinic Keratosis (AK) in Dermatology PracticesVideo
Aaron S. Farberg

Actinic Keratoses
Efficiently Implementing Photodynamic Therapy (PDT) for Actinic Keratosis (AK) in Dermatology PracticesVideo
Dawn L. Merritt