Pushing photodermatology into practice
Learn more about the impact of sun and light on the skin from Henry W. Lim, MD, FAAD, who presented the Clarence S. Livingood, MD Memorial Award and Lectureship.
Henry W. Lim, MD, FAAD, presented “Photodermatology: Past, Present, and Future” in the Clarence S. Livingood, MD Memorial Award and Lectureship during Sunday’s P151 – Plenary session.
Citing a lifelong interest in the subject, Dr. Lim took the audience on a journey through the emergence of photodermatology and the photobiology related to skin, including sun exposure and its consequences. Starting with the description of visible light by Sir Isaac Newton in 1669, Dr. Lim detailed the progress made in phototherapy, photodermatoses, and photoprotection through the ages.
He traced the current knowledge of photoaging, disease presentation differences between dark skin and light skin, and the impact of visible light + UVA1 on conditions aggravated by sun exposure. These included post-inflammatory hyperpigmentation and melasma, especially in skin of color.
Looking to the future
Using research that has propelled the field, Dr. Lim looked to the future and highlighted developments on the horizon.
- Citing a 2024 study showing that home phototherapy is non-inferior to office-based phototherapy for the treatment of plaque and guttate psoriasis, he said it might be considered as the first-line treatment option in the future.
- Photobiomodulation, a non-invasive form of phototherapy that uses wavelengths in the red light (RL, 620-700 nm) portion of the visible light (VL, 400-700 nm) spectrum and the near-infrared (NIR, 700-1440 nm) spectrum, could be used effectively to treat radiation dermatitis, mucositis, lymphedema, alopecia, ulcers, herpes simplex virus, acne, skin rejuvenation, wounds, and scars.
- Infrared radiation has been used with encouraging results in skin rejuvenation, wound healing, and hair restoration.
- More is being learned about the effect of outdoor air pollutants and their effects on aging and inflammatory diseases such as atopic dermatitis, cellulitis, as well as acne, hair loss, and possibly skin cancers.
- New knowledge of the biologic effects of electromagnetic radiation beyond the UV spectrum (VL, IR) and interactions with exposome and microbiome are emerging, Dr. Lim said.
“Skin microbiome has been shown to produce compounds that help to protect the skin from UVR, and sunscreen has the potential to reduce the diversity of the skin microbiome. Sunscreens that both provide protection against UVR and preserve the skin microbiome may offer additional benefits to skin health,” he said. However, Dr. Lim said additional studies are still needed.
Public education on photoprotection needs to continue, he said. Interaction with regulatory agencies and industry partners is essential to making sure the public has access to safe and effective sunscreens. Dermatologists are the only specialists who have the training and expertise to address photodermatology, including phototherapy.
“It is essential for us to continue to be the owner of this subspecialty by continued photodermatology education and practice,” Dr. Lim said.
