Light Therapy - Indications - Skin Conditions - Acne Vulgaris

Acne Vulgaris

Sunlight was long known to improve acne, and this was thought to be due to antibacterial and other effects of the ultraviolet spectrum which cannot be used as a long-term treatment due to the likelihood of skin damage.

It was found that some of the visible violet light present in sunlight (in the range 415–430 nm) activates a porphyrin (Coproporphyrin III) in Propionibacterium acnes which damages and ultimately kills the bacteria by releasing singlet oxygen. A total of 320 J/cm2 of light within this range renders the bacteria non-viable. Dr. Yoram Harth et al. were the first that issued a patent on the use of UV free high intensity Blue light for the treatment of acne. (United States Patent; 6,835,202 Harth, et al., December 28, 2004, Filed January 9, 2001, Apparatus and method for high energy photodynamic therapy of acne vulgaris and seborrhea). Based on this patent, and a clinical study, the FDA approved for the first time a medical device for the treatment of mild to moderate acne (Clearlight, by CureLIght Medical inc., FDA approval, 510K 013623, August 7, 2002). In 2003, a group at Bar Ilan University in Israel, proved in lab condition the eradication of the acne bacteria by exposure to blue light. ( Eradication of Propionibacterium acnes by its endogenic porphyrins after illumination with high intensity blue light. Ashkenazi H, Malik Z, Harth Y, Nitzan Y. FEMS Immunol Med Microbiol 2003 Jan 21 35:1 17–24.) Later in 2003 a peer reviewed clinical study proved in the first time the clinical effect of blue light on acne lesions. (The effective treatment of acne vulgaris by a high-intensity, narrow band 405–420 nm light source. Elman M, Harth Y, Slatkine M. J Cosmet Laser Ther. 2003 Jun;5(2):111-7.)

Since there are few porphyrins naturally found in the skin, the treatment is believed safe except in patients with porphyria; although eye protection is used due to light-sensitive chemicals in the retina. The first FDA approved blue light system to be approved by the FDA was based on Metal halide lamps custom made to emit most of it energy at 405–420 nm . (Clearlight, by CureLIght Medical inc., FDA approval, 510K 013623, August 7, 2002). Other blue light systems use LEDs. Overall improvements of on average 76% for 80% of patients occurs over three months; most studies show that it performs better than benzoyl peroxide and the treatment is far better tolerated. However, approximately 10% of users see no improvement.