Light emitting diodes (LEDs) have become the main light sources for general lighting, due to their high lumen efficiency and long life time. Moreover, their high bandwidth and the availability of diverse wavelength contents ranging from ultraviolet to infrared empower them with great controllability in tuning brightness, pulse durations and spectra. These parameters are the essential ingredients of the applications in medical imaging and therapies. Despite the fast advances in both LED technologies and their applications, few reviews have been seen to link the controllable emission properties of LEDs to these applications. The objective of this paper is to bridge this gap by reviewing the main control techniques of LEDs that enable creating enhanced lighting patterns for imaging and generating effective photon doses for photobiomodulation. This paper also provides the basic mechanisms behind the effective LED therapies in treating cutaneous and neurological diseases. The emerging field of optogenetics is also discussed with a focus on the application of LEDs. The multidisciplinary topics reviewed in this paper can help the researchers in LEDs, imaging, light therapy and optogenetics better understand the basic principles in each other's field; and hence to stimulate the application of LEDs in health care.

OBJECTIVE: To investigate whether nutritional intervention with a proprietary formulation and other micronutrients may favourably alter skin roughness and elasticity. METHODS: Sixty-two women aged 45-73 years participated in a double-blind, placebo-controlled trial testing the efficacy of a proprietary oral supplement for skin nutrition (Evelle), for improvement of skin elasticity and roughness. The active ingredients were vitamins C and E, carotenoids, selenium, zinc, amino acids and glycosaminoglycans, blueberry extract and Pycnogenol. RESULTS: Skin elasticity, measured using an optical cutometer, was found to be statistically significantly increased by 9% after 6 weeks of treatment compared with placebo (p=0.0351). Skin roughness, as evaluated by three-dimensional microtopography imaging, was found to be statistically significantly lowered by 6% compared with the control group after 12 weeks treatment (p=0.0157). CONCLUSION: Evelle can potentially improve visible signs of cutaneous ageing. 

BACKGROUND:Skin fibrosis is a debilitating condition that significantly impacts patient quality of life. Ultraviolet phototherapy is currently used to treat several diseases featuring skin fibrosis. High-fluence light-emitting diode-generated red light (HF-LED-RL) does not cause DNA damage associated with skin cancer, and it is generally regarded as safe, portable, and cost-effective. Early clinical observations suggest that LED-generated light may possess antifibrotic effects, although these findings are largely unexplored. Previously published research demonstrated that HF-LED-RL decreases fibroblast proliferation and collagen in vitro.

OBJECTIVE:The goal of this study was to compare the combination effects of HF-LED-RL alone with HF-LED-RL in combination with resveratrol.

MATERIALS AND METHODS:It is hypothesized that resveratrol, an active ingredient in red wine, a potent antioxidant scavenger of reactive oxygen species, and an inhibitor of collagen production, may synergistically decrease fibroblast proliferation and collagen production when combined with HF-LED-RL.

RESULTS:In this study, evidence is provided that resveratrol combined with HF-LED-RL acts synergistically to decrease fibroblast proliferation and procollagen 1A1 production, and this represents a new potential therapeutic modality that is termed the"photobotanical"effect due to the combined light and botanical properties observed.

CONCLUSION:The study, discovery, and use of photobotanical combinations may usher in new therapeutics or phototherapy adjuvants for the treatment of dermatologic diseases.

BACKGROUND:Skin fibrosis is a debilitating condition that significantly impacts patient quality of life. Ultraviolet phototherapy is currently used to treat several diseases featuring skin fibrosis. High-fluence light-emitting diode-generated red light (HF-LED-RL) does not cause DNA damage associated with skin cancer, and it is generally regarded as safe, portable, and cost-effective. Early clinical observations suggest that LED-generated light may possess antifibrotic effects, although these findings are largely unexplored. Previously published research demonstrated that HF-LED-RL decreases fibroblast proliferation and collagen in vitro.

OBJECTIVE:The goal of this study was to compare the combination effects of HF-LED-RL alone with HF-LED-RL in combination with resveratrol.

MATERIALS AND METHODS:It is hypothesized that resveratrol, an active ingredient in red wine, a potent antioxidant scavenger of reactive oxygen species, and an inhibitor of collagen production, may synergistically decrease fibroblast proliferation and collagen production when combined with HF-LED-RL.

RESULTS:In this study, evidence is provided that resveratrol combined with HF-LED-RL acts synergistically to decrease fibroblast proliferation and procollagen 1A1 production, and this represents a new potential therapeutic modality that is termed the"photobotanical"effect due to the combined light and botanical properties observed.

CONCLUSION:The study, discovery, and use of photobotanical combinations may usher in new therapeutics or phototherapy adjuvants for the treatment of dermatologic diseases.