Long-pulsed Nd:YAG laser-assisted hair removal in pigmented skin: a clinical and histological evaluation

Abstract

Objective: To determine the safety and effectiveness of a long-pulsed Nd:YAG laser at 1064 nm in effecting long-term hair reduction in patients with darkly pigmented skin.

Design: Nonrandomized before-after clinical and histological trial.

Setting: Private practice, ambulatory care facility.

Patients: Twenty women with skin phototypes IV through VI and dark brown to black terminal hair on the face, axillae, or legs.

Intervention: A series of 3 long-pulsed (50-millisecond) 1064-nm Nd:YAG laser treatments at fluences ranging from 40 to 50 J/cm(2) were delivered to the identified treatment areas on a monthly basis by a single operator.

Main outcome measures: Global clinical grading scores of comparable before-after treatment photographs were determined by 2 independent medical assessors during each laser session and 1, 3, 6, and 12 months postoperatively. A dermatopathologist reviewed unmarked histological specimens obtained at baseline, immediately after the initial laser treatment, and at 1 and 6 months after the final laser session.

Results: Substantial hair reduction was seen after each of the 3 treatment sessions. Prolonged hair loss was observed 12 months after the final laser treatment (70%-90% hair reduction). Axillary hair was substantially more responsive to laser irradiation than was hair located on the legs and face. Adverse effects included mild to moderate treatment pain and rare occurrences of vesiculation and transient pigmentary alteration without fibrosis or scarring. Histological tissue changes mirrored clinical response rates, with evidence of selective follicular injury without epidermal disruption.

Conclusion: The long-pulsed 1064-nm Nd:YAG laser is a safe and effective method of long-term hair reduction in patients with darkly pigmented skin.