Treatment of Mild-to-Moderate Plaque Psoriasis with a New 650-Microsecond 1064-nm Nd:YAG Laser: Clinical and Dermoscopic Assessment

INTRODUCTION: About 70–80% of patients with psoriasis suffer from mild disease, and new modalities of topical treatment are urgently needed. This study aims to evaluate the effectiveness of 650-microsecond 1064-nm Nd:YAG laser in the therapy of psoriatic plaques and assess the utility of dermoscopy in predicting treatment response. METHODS: Ten patients (mean age 37.4 ± 16.2 years) with stable plaque-type psoriasis were enrolled. The microsecond Nd:YAG laser treatment was applied to representative plaques on day 0, 7, 14, and 21. Clinical and dermoscopic photographs were performed at each session and follow-up visit (day 28). The disease severity was assessed using modified Psoriasis Area and Severity Index (mPASI) and Investigator Global Assessment (IGA). Patients were asked to rate the intensity of subjective symptoms, tolerability, and final outcome of the treatment. RESULTS: Significant improvement of all mPASI components was observed, although the maximal mean reduction of total mPASI was only 30.3%. At baseline, three patients were assessed as “moderate” and seven as “mild” according to IGA, while on day 28, eight patients were scored as “mild” and two as “almost clear.” Complete resolution of itching was achieved in all patients. Local adverse reactions were also observed, which resulted in moderate tolerance of treatment in four patients. Three participants reported marked improvement on day 28, although 30% of patients observed no benefit. All subjects with dotted vessels, linear vessels, or hemorrhagic spots under dermoscopy at baseline reported some improvement after laser therapy. Three out of six patients with globular vessels were unresponsive to Nd:YAG laser. CONCLUSIONS: Microsecond Nd:YAG laser treatment may provide some improvement of psoriatic plaques, but its routine applicability seems to be limited due to ambiguous efficacy and local adverse reactions. Dermoscopy may be useful in identifying patients who will benefit from the procedure.