Visible light. Part I: Properties and cutaneous effects of visible light (original) (raw)
Related papers
Effects of Visible Light on the Skin
Photochemistry and Photobiology, 2008
Electromagnetic radiation has vast and diverse effects on human skin. Although photobiologic studies of sunlight date back to Sir Isaac Newton in 1671, most available studies focus on the UV radiation part of the spectrum. The effects of visible light and infrared radiation have not been, until recently, clearly elucidated. The goal of this review is to highlight the effects of visible light on the skin. As a result of advances in the understanding of skin optics, and comprehensive studies regarding the absorption spectrum of endogenous and exogenous skin chromophores, various biologic effects have been shown to be exerted by visible light radiation including erythema, pigmentation, thermal damage and free radical production. It has also been shown that visible light can induce indirect DNA damage through the generation of reactive oxygen species. Furthermore, a number of photodermatoses have an action spectrum in the visible light range, even though most of the currently available sunscreens offer, if any, weak protection against visible light. Conversely, because of its cutaneous biologic effects, visible light is used for the treatment of a variety of skin diseases and esthetic conditions in the form of lasers, intense pulsed light and photodynamic therapy.
Different Wavelengths of LEDs on Cutaneous Wound Healing in Wistar Rats
Journal of Basic & Applied Sciences, 2015
This study evaluates different wavelengths of LED therapy in Wistar rats skin injuries. LEDs (Light Emitting Diodes) are phototherapeutic resource nowadays, since it is considered a good alternative to Low Level Laser Therapy in injury healing because of the lower cost. Twenty-five male Wistar rats were divided in five groups: Control, Red LED (630-780 nm), Green LED (490-565 nm), Blue LED (440-490 nm) and Yellow LED (590-630 nm). It´s a experimental research that it was performed during 4 weeks. Twenty-four hours after surgical injury (1cm²) was applied LED therapy for 6 minutes during five days. Red LED presented best anti-edematous effects in comparison to the other wavebands. The perimeters were reduced in all groups, but in Green and Red LED groups were significantly diminished (p
Lasers in Medical Science, 2013
Sensitive skin is a relatively common dermatologic condition and no optimal treatments have been established so far. Low-level laser/light therapy (LLLT) has been used for its biostimulative effect in various clinical settings. The purpose of this study was to investigate whether low-level laser/light therapy can improve sensitive skin clinically and to evaluate the effects of LLLT on skin in vitro. Twenty-eight patients complaining of sensitive skin were treated with low-level polarized light, and clinical results were evaluated using subjective and objective method. To investigate possible working mechanism of LLLT on skin, cultured human keratinocytes pretreated with nontoxic concentration of sodium lauryl sulfate (SLS) were used. Cytokines released from irritated keratinocytes after LLLT were analyzed. All patients showed subjective and objective improvement after treatment. No adverse effects were reported. The average number of LLLT sessions required to achieve clinical improvement was 9.9, and cumulative dose of LLLT was 71.3 J/cm 2 on the average. Erythema index decreased significantly after LLLT treatment (p=0.017). In vitro assay showed that LLLT significantly reduced the release of VEGF from SLS-pretreated keratinocytes (p=0.021). Our results suggest that LLLT could be a useful and safe treatment modality for sensitive skin, and modification of inflammatory cytokines released from irritated keratinocytes may be considered as one of plausible mechanisms in sensitive skin treated with LLLT.
The Journal of clinical and aesthetic dermatology, 2018
Within the field of dermatology, advances in the use of light emitting diodes (LEDs) have led to their clinical application for a variety of medical and cosmetic uses. Of note, one phototherapy device has demonstrated beneficial effects over a range of clinical applications (Omnilux™; GlobalMed Technologies, Glen Ellen, California). The study included a literature review of published studies. Using LEDs with frequencies of 415nm (blue), 633nm (red), and 830nm (infrared), this device has demonstrated significant results for the treatment of medical conditions, including mild-to-moderate acne vulgaris, wound healing, psoriasis, squamous cell carcinoma in situ (Bowen's disease), basal cell carcinoma, actinic keratosis, and cosmetic applications. Although photodynamic therapy with the photosensitizer 5-aminolevulinic acid might cause stinging and burning, phototherapy is free of adverse events. We determined that phototherapy using LEDs is beneficial for a range of medical and aesth...
Lasers in Medical Science, 2015
From the very first reports describing the method of action of phototherapy, the effects have been considered to be the result of photochemical and photophysical interactions between the absorbed photons and tissue and not related to secondary changes in tissue or skin temperature. However, thermal effects have been recently reported in dark pigmented skin when irradiated with single wavelengths of 810 and 904 nm of low-level laser therapy (LLLT) devices even with doses that do not exceed those recommended by the World Association of Laser Therapy (WALT). The aim of this study was to evaluate the thermal impact during the concurrent use of pulsed red and infrared LEDs and super-pulsed lasers when applied to light, medium, and dark pigmented human skin with doses typically seen in clinical practice. The study evaluated the skin temperature of 42 healthy volunteers (males and females 18 years or older, who presented different pigmentations, stratified according to Von Luschan's chromatic scale) via the use of a thermographic camera. Active irradiation was performed with using the multi-diode phototherapy cluster containing four 905-nm super-pulsed laser diodes (frequency set to 250 Hz), four 875-nm infrared-emitting diodes, and four 640-nm LEDs (manufactured by Multi Radiance Medical™, Solon, OH, USA). Each of the four doses were tested on each subject: placebo, 0 J (60 s); 10 J (76 s); 30 J (228 s); and 50 J (380 s). Data were collected during the last 5 s of each dose of irradiation and continued for 1 min after the end of each irradiation. No significant skin temperature increases were observed among the different skin color groups (p>0.05), age groups (p>0.05), or gender groups (p>0.05). Our results indicate that the concurrent use of super-pulsed lasers and pulsed red and infrared LEDs can be utilized in patients with all types of skin pigmentation without concern over safety or excessive tissue heating. Additionally, the doses and device utilized in present study have demonstrated positive outcomes in prior clinical trials. Therefore, it can be concluded that the effects seen by the concurrent use of multiple wavelengths and light sources were the result of desirable photobiomodulation effect and not related to thermal influence.
Annals of the New York Academy of Sciences, 1985
Photobiology is the study of the interactions of optical nonionizing electromagnetic radiation (ultraviolet, visible, and near infrared) with biomolecules and the resulting biologic responses. These responses are initiated by in vivo photochemistry; specific wavelength and molecular absorbing properties result in electronic excitation or nonspecific kinetic (thermal) excitation of molecules by radiation.
Journal of cosmetic and laser therapy : official publication of the European Society for Laser Dermatology, 2005
A major cause of skin aging is a chronic micro-inflammation triggered by UV radiation and external pollutants. It has been demonstrated that blue light diminishes inflammatory conditions and near infrared light enhances circulation. To assess the effectiveness of a non thermal dual wavelength -- blue (405 - 420 nm) and near infrared (850 - 900 nm) -- light source in skin rejuvenation, in the reduction of the duration of post skin resurfacing erythema and in the acceleration of healing of post surgical conditions (face lift and breast augmentation). We have utilized a non contact, hand free dual wavelength light source (iClearXL and Clear100XL, Curelight Ltd) to treat over 60 patients and perform three controlled studies in four centers. Follow up duration was three months. Control group for photo-rejuvenation consisted of patients treated with Glycolic peeling and daily appliance of vitamin C Control group for post skin resurfacing erythema duration consisted of patients untreated b...
2006
From 2001 to 2005, work was conducted at the Photobiology Unit at Ninewells Hospital in Dundee to examine the optical radiation environment and its implications for normal and diseased skin. Artificial sources of radiation were considered within the contexts of the hazards posed, measurement of the hazards, regulation concerning exposure and sources, and protection of abnormal skin from adverse ffects.From 2001 to 2005, work was conducted at the Photobiology Unit at Ninewells Hospital in Dundee to examine the optical radiation environment and its implications for normal and diseased skin. Artificial sources of radiation were considered within the contexts of the hazards posed, measurement of the hazards, regulation concerning exposure and sources, and protection of abnormal skin from adverse ffects. The hazards posed by both ultraviolet (UV) and visible polychromatic sources were examined for normal and abnormal (chronic actinic dermatitis and solar urticaria) skin in an effort to p...