Photobiomodulation CME part II: Clinical applications in dermatology.

Photobiomodulation (PBM) is an emerging treatment modality in dermatology with increasing office and home-based use. PBM is the use of various light sources in the red light (620-700 nm) and near-infrared (700-1440 nm) spectrum as a form of light therapy. PBM is often administered through low-level lasers or light-emitting diodes. Studies show that PBM can be used effectively to treat conditions secondary to cancer therapies, alopecia, ulcers, herpes simplex virus, acne, skin rejuvenation, wounds, and scars. PBM offers patients many benefits compared to other treatments. It is noninvasive, cost-effective, convenient for patients, and offers a favorable safety profile. PBM can be used as an alternative or adjuvant to other treatment modalities including pharmacotherapy. It is important for dermatologists to gain a better clinical understanding of PBM for in-office administration and to counsel patients on proper application for home-use devices to best manage safety and expectations as this technology develops. PBM wavelengths can induce varied biological effects in diverse skin types, races, and ethnicities; therefore, it is also important for dermatologists to properly counsel their skin of color patients who undergo PBM treatments. Future clinical trials are necessary to produce standardized recommendations across conditions and skin types.

Photobiomodulation CME Part I: Overview and Mechanism of Action.

Photobiomodulation (PBM), previously known as low-level laser light therapy, represents a non-invasive form of phototherapy that utilizes 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. PBM is a promising and increasingly used therapy for the treatment of various dermatologic and non-dermatologic conditions. Photons from RL and NIR are absorbed by endogenous photoreceptors including mitochondrial cytochrome C oxidase (COX). Activation of COX leads to the following changes: modulation of mitochondrial adenosine triphosphate (ATP), generation of reactive oxygen species (ROS), and alterations in intracellular calcium levels. The associated modulation of ATP, ROS and calcium levels promotes the activation of various signaling pathways (e.g., insulin-like growth factors, phosphoinositide 3-kinase pathways), which contribute to downstream effects on cellular proliferation, migration and differentiation. Effective PBM therapy is dependent on treatment parameters (e.g., fluence, treatment duration and output power). PBM is generally well-tolerated and safe with erythema being the most common and self-limiting adverse cutaneous effect.

Integrating skin color assessments into clinical practice and research: A review of current approaches.

Skin color classification can have importance in skin health, pigmentary disorders, and oncologic condition assessments. It is also critical for evaluating disease course and response to a variety of therapeutic interventions and aids in accurate classification of participants in clinical research studies. A panel of dermatologists conducted a literature review to assess the strengths and limitations of existing classification scales, as well as to compare their preferences and utilities. We identified 17 skin classification systems utilized in dermatologic settings. These systems include a range of parameters such as UV light reactivity, race, ethnicity, and degree of pigmentation. The Fitzpatrick skin type classification is most widely used and validated. However it has numerous limitations including its conflation with race, ethnicity, and skin color. There is a lack of validation data available for the remaining scales. There are significant deficiencies in current skin classification instruments. Consensus-based initiatives to drive the development of validated and reliable tools are critically needed.

A narrative review of the impact of ultraviolet radiation and sunscreen on the skin microbiome.

BACKGROUND: The human skin microbiome is a dynamic ecosystem that plays an important role in skin health. The skin microbiome has been implicated in numerous diseases, and our knowledge surrounding it continues to evolve. A better understanding of the interactions between the environment and the skin microbiome will lead to improvements in skin health. METHODS: This article reviews the published literature surrounding the impact of ultraviolet radiation (UVR) and sunscreen on the skin microbiome. RESULTS: Skin microbes are differentially impacted by UVR, and alterations in the microbiome can be detected following UVR exposure. These changes are related to direct bactericidal effects, alterations in the cutaneous metabolome, and changes in the cutaneous immune system. UV filters used in sunscreen have been shown to have bactericidal effects, and many compounds used in sunscreen emulsions can also negatively impact cutaneous microbes. CONCLUSION: A healthy microbiome has been shown to produce compounds that help protect the skin from UVR, and sunscreen has the potential to reduce the diversity of the skin microbiome. This indicates that designing sunscreen products that both provide protection against UVR and preserve the skin microbiome may offer additional benefits to skin health when compared with traditional sunscreen products.

Subjective and objective assessment of color match of universal tinted sunscreens in Fitzpatrick skin phototypes I-VI.

BACKGROUND: Tinted sunscreens not only shield against UV rays but also provide protection against visible light, as opposed to traditional sunscreens. Universal tinted sunscreens are marketed to complement all skin tones. OBJECTIVE: To assess color match and subject satisfaction for 7 universal tinted sunscreens across various price ranges in all Fitzpatrick skin phototypes (SPT). METHODS: Products A-G were applied at concentrations of 1 and 2 mg/cm2 on the dorsal arms of 30 subjects spanning SPT I-VI. Photography, colorimetry, and subject and investigator surveys were utilized to determine color match. RESULTS: Using colorimetry analysis at the recommended 2 mg/cm2 concentration, two of seven products were identified as suitable matches for SPT I-II, while six out of seven were determined to be a good match for SPT III-IV. However, only one product was found to be a good match for SPT V-VI at the recommended concentration according to colorimetry results. CONCLUSION: Universal tinted sunscreens do not provide an adequate color match for all skin phototypes, especially for individuals with very fair or very dark skin tones.

Reliability of the Vitiligo Area Scoring Index measurement tool for vitiligo.

Background: A reliable instrument is needed to assess vitiligo severity and treatment response. Objective: To assess inter- and intrarater variability and accuracy of the Vitiligo Area Scoring Index among trained raters and to evaluate a proposed Vitiligo Area Scoring Index using equidistant 10% depigmentation increments (VASI 10%). Methods: In this prospective study, 12 raters evaluated images of 10 participants with vitiligo on 2 occasions using total body Vitiligo Area Scoring Index (T-VASI) and facial Vitiligo Area Scoring Index (F-VASI) scores after training. Inter- and intrarater reliabilities and accuracy vs digital scores were determined using intraclass correlation coefficients. VASI 10% scores were evaluated separately for interrater reliability and accuracy. Results: F-VASI interrater reliability improved from "moderate" to "good" between time points, while T-VASI was "good" at both time points. Intrarater reliability ranged from "good" to "excellent" for T-VASI and "poor" to "excellent" for F-VASI. Accuracy intraclass correlation coefficient was "good" to "excellent" for most raters. Interrater reliability using VASI 10% was "moderate" for both T-VASI and F-VASI. Limitations: Small participant population and number of raters; participants were not assessed in person; no repeated VASI 10% measures. Conclusion: Vitiligo Area Scoring Index generally provides good to excellent reliability for assessment of vitiligo by raters who receive standardized training.