Background and objectives: Low fluence Q-switched neodymium-doped yttrium aluminum garnet (Nd:YAG) lasers are widely applied for facial depigmentation. Nonetheless, few reports analyze the general outcome, complications, of single and combined therapy of 532/1064-nm Nd:YAG lasers in Asian patients with Fitzpatrick type IV skin.
Study design/materials and methods: We retrospectively reviewed all consecutive patients who completed 5 consecutive sessions at 1-month intervals of treatment with 1064-nm (spot size: 5-7 mm, 1.5-2.0 J/cm) or combined with 532-nm (spot size, 2-3 mm; 0.5-1.5 J/cm) Nd:YAG laser (Laseroptek, Korea) from October 2011 to March 2013. The patients, laser surgeon, and 3 blinded reviewers assessed the outcomes and complications. Improvement was graded as follows: 1, 0%-25%; 2, 26%-50%; 3, 51%-75%; 4, 76-90%; and 5, greater than 90%. Postinflammatory hyperpigmentation (PIH) was documented according to the severity (1, slight; 2, moderate; 3, severe; and 4, extreme). Other post-laser side effects were also documented (eg, scaling, dryness, erythema, and pruritus).
Results: Four male patients and 37 female patients were included with a mean age of 38.5 years (SD, 10.1 years). There were no significant differences on patients', surgeon's, or blinded reviewers' improvement gradings. (4.11 ± 0.62 vs 4.30 ± 0.46, P = 0.54; 3.88 ± 0.66 vs 3.89 ± 0.31, P = 0.50; 3.30 ± 0.69 vs 3.74 ± 0.38, P = 0.34). Transient minor side effect occurred as follows: erythema in 9 (22%), pruritus in 7 (17%), dryness in 6 (15%), and scaling in 6 (15%). There was no risk difference in these side effects between groups. The PIH scores were slight in 10 patients (4 in single and 6 in combined), severe in 4 (3 in single and 1 in combined), and extreme in 1 (single therapy). The PIH incidence also did not differ (33.3%, 35.3%; P = 0.58).
Conclusions: We reported satisfactory outcomes after low-fluence Q-switched sole 1064-nm or combined 532/1064-nm therapy. The outcome and complication profiles did not differ between the groups. The PIH incidence was not low, but usually transient. The incidence of severe or extreme PIH was rare.