A comparative split-face study of photodynamic therapy with indocyanine green and indole-3-acetic acid for the treatment of acne vulgaris

Background Recently, photodynamic therapy (PDT) using a variety of light sources and photosensitizers has been used for the treatment of acne vulgaris. PDT with aminolaevulinic or methylaminolaevulinic acid has also been used in clinical trials as a treatment for acne, but adverse effects such as pain, erythema and pustular eruption are common. Indocyanine green (ICG) and indole-3-acetic acid (IAA), newer photosensitizers, are known to have minimal adverse effects. Objectives This study was designed to compare the safety and efficacy of PDT using ICG and PDT using IAA in the treatment of mild to moderate acne vulgaris. Methods In this prospective, single-blind, clinical trial, 34 patients with mild to moderate acne were treated with IAA with green light (520 nm) on half of the face and with ICG with near-infrared radiation (805 nm) on the other half. The procedure was carried out five times at 1-week intervals. Results With regard to acne lesions (inflammatory and noninflammatory) and sebum secretion, there were statistically significant reductions at each time point compared with the baseline values (P < 0.05). However, there were no statistically significant differences between the two treatment types (P > 0.05). Both ICG-PDT and IAA-PDT showed better responses for inflammatory lesions than for noninflammatory lesions (P < 0.05). Subjective satisfaction score were statistically significant at 4 and 5 weeks of treatment as well as at 1, 2 and 3 months follow-up (P < 0.05). Conclusions Both PDT with ICG and PDT with IAA are safe and effective for the treatment of mild to moderate acne vulgaris.