Low-fluence 585 nm Q-switched Nd:YAG laser: a novel laser treatment for post-acne erythema

Abstract

Background: Persistent post-acne erythema is one of the most common aesthetic sequelae to arise after active acne resolves. The treatment remains challenging due to lack of effective laser modalities.

Objectives: To evaluate the safety and efficacy of a low-fluence 585 nm Q-switched Nd:YAG laser for the treatment of post-acne erythema.

Materials & methods: Twenty-five patients with post-acne erythema were treated with a low-fluence Q-switched Nd:YAG laser using the 585 nm Gold Toning™ handpiece (5 mm spot size, 5-10 ns, 0.30-0.55 J/cm(2) , 2-4 passes) for three sessions at 2-week intervals. Erythema lesion (macules) count, inflammatory acne (papules, pustules) count, erythema index, degree of post-acne erythema and overall improvement in post-acne erythema and acne scar were assessed at baseline, every 2 weeks and 6 weeks after the last treatment. Subjective degrees of satisfaction were also evaluated. Adverse events were recorded and pain was scored using a visual analog scale (VAS).

Results: At 6 weeks after 3 sessions of laser treatment, all patients demonstrated clinical improvement. Erythema lesion counts decreased by 20.1% (versus baseline) after the first treatment (P = 0.004), by 32.7% after the second treatment, by 46.5% at 2 weeks after the third treatment and by 58.7% at the 6-week follow-up (all P < 0.001). Significant improvements were also noted in erythema indices (22.29 ± 2.4 to 17.51 ± 1.8) and mean post-acne erythema scores after the first treatment (both P < 0.001). The mean scores of independent physician assessments were 4.04 ± 0.9 in term of the improvement of post-acne erythema and 3.44 ± 0.9 in the improvement of scarring. In addition, we could observe a significant decrease in inflammatory acne lesion counts after two laser treatments with a decrease in mean lesion counts by 67% at the 6-week follow-up. Treatment was well-tolerated and adverse effects were limited to transient erythema and edema at treatment sites.

Conclusions: Low-fluence 585 nm Q-switched Nd:YAG laser treatment is safe and effective for the treatment of post-acne erythema with minimal discomfort and quantifiable improvement in the appearance of early acne scarring and inflammatory acne.

Keywords: 585nm Q-Switched Nd:YAG Laser; Acne; Post-acne erythema.