[Light-emitting diodes (LED)]

Clinical efficacy of home-use blue-light therapy for mild-to moderate acne

INTRODUCTION

Blue-light light-emitting diode (LED) therapy has become widely used for the treatment of inflammatory acne. In this study we evaluated the efficacy of a home use blue-light LED application in improving lesions and shortening their time to clearance.

METHODS

This was an IRB approved randomized self-control study. For each patient (n = 30), 2 similar lesions, one of each side of the face were chosen for treatment with either a blue-light LED hand-held or sham device. Treatments (n = 4) were conducted twice daily in the clinic and lesions were followed-up till resolution. Reduction in blemishes size and erythema and the overall improvement were evaluated by both the physician and the patients. Time to lesion resolution was recorded.

RESULTS

There was a significant difference in the response of lesions to the blue-light LED application as opposed to the placebo in terms of reduction in lesion size and lesion erythema as well as the improvement in the overall skin condition (p < 0.025). Signs of improvement were observed as early as post 2 treatments. Time to resolution was significantly shorter for the blue-light LED therapy.

CONCLUSION

The results support the effectiveness of using blue-light LED therapy on a daily basis for better improvement and faster resolution of inflammatory acne lesions.

LED (660 nm) and laser (670 nm) use on skin flap viability: angiogenesis and mast cells on transition line

Skin flap procedures are commonly used in plastic surgery. Failures can follow, leading to the necrosis of the flap. Therefore, many studies use LLLT to improve flap viability. Currently, the LED has been introduced as an alternative to LLLT. The objective of this study was to evaluate the effect of LLLT and LED on the viability of random skin flaps in rats. Forty-eight rats were divided into four groups, and a random skin flap (10 × 4 cm) was performed in all animals. Group 1 was the sham group; group 2 was submitted to LLLT 660 nm, 0.14 J; group 3 with LED 630 nm, 2.49 J, and group 4 with LLLT 660 nm, with 2.49 J. Irradiation was applied after surgery and repeated on the four subsequent days. On the 7th postoperative day, the percentage of flap necrosis was calculated and skin samples were collected from the viable area and from the transition line of the flap to evaluate blood vessels and mast cells. The percentage of necrosis was significantly lower in groups 3 and 4 compared to groups 1 and 2. Concerning blood vessels and mast cell numbers, only the animals in group 3 showed significant increase compared to group 1 in the skin sample of the transition line. LED and LLLT with the same total energies were effective in increasing viability of random skin flaps. LED was more effective in increasing the number of mast cells and blood vessels in the transition line of random skin flaps.