A split-face, single-blinded, randomized controlled comparison of alexandrite 755-nm picosecond laser versus alexandrite 755-nm nanosecond laser in the treatment of acquired bilateral nevus of Ota-like macules

Abstract

Background: Q-switched alexandrite lasers (QSALs) have been used for the treatment of acquired bilateral nevus of Ota-like macules (ABNOMs). Currently, picosecond alexandrite laser (PSAL) pulses have become available for pigmentary disorders. However, no studies have compared PSAL and QSAL in the treatment of ABNOM.

Objective: We sought to compare the efficacy and safety of PSAL and QSAL in the treatment of ABNOM.

Methods: Each patient (n = 30) received 3 treatments at 6-month intervals. Matching areas were delimitated on the face of each patient (left/right comparison); 1 side was treated with PSAL and the other side was treated with QSAL. The safety and efficacy of the 2 lasers were determined by visual assessment and self-report from patients 6 months after the final treatment.

Results: The PSAL-treated area achieved significantly better clearance (3.73 vs 2.4) with less severe pain (4.47 vs 5.16). The incidence rate of postinflammatory hyperpigmentation was 27.77% and 54.44% for the PSAL and QSAL treatments, respectively, and the duration of postinflammatory hyperpigmentation was 1.32 and 1.74 months, respectively (P < .001).

Limitations: The limitations of our study include the small sample size and the lack of objective evaluation.

Conclusion: Compared with QSAL, PSAL therapy afforded significantly better clinical outcomes and fewer side effects in the treatment of ABNOM.

Keywords: Q-switched alexandrite laser; acquired bilateral nevus of Ota–like macules; photomechanical effect; picosecond alexandrite laser; postinflammatory hyperpigmentation.