Photosensitivity Testing in Future : Application of LED Wood’s lamp and targeted narrow-band UVB

Abstract

For the diagnosis of photosensitivity diseases, experimental induction of an eruption is of the most importance. Fluorescent lamps, such as black lights and sunlamps, have been used as light sources for phototesting. At the present time, however, both lamps are not commercially available because of the usage of mercury in the tubes. Recently, LED Wood’s lamp has been developed for examination of skin disorders including bacterial infection, fungal infection, porphyria, and pigment disorders. The LED Wood’s lamp emits UVA similarly to that of a fluorescent black light. Based on this characteristic, we used LED Wood’s lamp and also a targeted narrow-band UVB lamp as UVA and UVB light sources, respectively, for phototesting. Phototoxicity of 8-methoxypsoralen was induced in a normal subject using a LED Wood’s lamp, and polymorphous light eruption was produced in a photosensitive patient by exposure to LED Wood’s lamp and targeted narrow-band UVB. These mercury-free devices are much more convenient than conventional apparatuses because of their compact size and inexpensiveness. Skin Research, 20 : 1-5, 2021