Treatment of linear and whorled nevoid hypermelanosis using QS 694-nm ruby laser.

Laser is being widely used in treating pigmented lesions nowadays. Linear and whorled nevoid hypermelanosis (LWNH) is a rare pigmentary anomaly, and there are only a handful of cases of successful treatment, all with QS 532- and 755-nm laser. The objective of this study was to examine the clinical outcome of QS 694-nm ruby laser in the treatment of LWNH. We report on a 4-year-old boy presented with asymptomatic macular hyperpigmentation over the entire cheek who underwent 3 treatment sessions with QS 694-nm ruby laser. One month after the last treatment, the patient demonstrated significant improvement to the treatment area. Aside from post-procedural purpura lasting approximately 1 week, the patient experienced no serious adverse effects. No recurrence was observed during the 3-month follow-up. Given the excellent results seen in our patients, we recommended the use of QS 694-nm ruby laser as a safe and effective treatment in patients with LWNH.