Near-visible light and UV photoprotection in the treatment of melasma: a double-blind randomized trial

作者：Pablo Castanedo Cazares Juan; Hernandez Blanco Diana; Carlos Ortega Blanca; Fuentes Ahumada Cornelia; Torres Alvarez Bertha^*

来源：Photodermatology Photoimmunology & Photomedicine, 2014, 30(1): 35-42.

DOI：10.1111/phpp.12086

• iron oxide
• melasma
• photoprotection
• sunscreens
• visible light

BackgroundMelasma is an acquired hyperpigmentation on sun-exposed areas. Multiple approaches are used to treat it, but all include broad ultraviolet (UV)-spectrum sunscreens. Visible light (VL) can induce pigmentary changes similar to those caused by UV radiation on darker-skinned patients.
ObjectiveTo assess the efficacy of sunscreen with broad-spectrum UV protection that contains iron oxide as a VL-absorbing pigment (UV-VL) compared with a regular UV-only broad-spectrum sunscreen for melasma patients exposed to intense solar conditions.
MethodsSixty-eight patients with melasma were randomized in two groups to receive either UV-VL sunscreen or UV-only sunscreen, both with sun protection factor50, over 8 weeks. All patients received 4% hydroquinone as a depigmenting treatment. At onset and at conclusion of the study, they were assessed by the Melasma Activity and Severity Index (MASI; a subjective scale), colorimetry (L*) and histological analysis of melanin.
ResultsSixty-one patients concluded the study. At 8 weeks, the UV-VL group showed 15%, 28% and 4% greater improvements than the UV-only group in MASI scores, colorimetric values and melanin assessments, respectively.
ConclusionsUV-VL sunscreen enhances the depigmenting efficacy of hydroquinone compared with UV-only sunscreen in treatment of melasma. These findings suggest a role for VL in melasma pathogenesis.

• 出版日期2014-2