Indications

A positive result is when there is a pigmentary disorder that is obvious, or the fluorescence is noted. The Wood’s lamp is often used to make a diagnosis of the following skin disorders: ● Disorders of pigmentation like melasma, vitiligo ● Pityriasis versicolor which presents as a rash on the chest or back – the rash will emit an orange glow. ● Tinea capitis will reveal areas of baldness, and the Microsporum species will fluoresce blue-green – however, many other fungal infections may not fluoresce with Wood’s lamp ● Scabies and head lice ● Erythrasma caused by Corynebacterium which presents as pigmented rash in the skin folds ● Pseudomonas which will fluoresce green

A Wood’s lamp is also used to look for signs of porphyria in erythrocytes, stool, and urine. Sometimes beauticians may assess for skin imperfections and signs of aging with a Wood’s lamp. When a slit lamp is unavailable, the ophthalmologist may use the Wood lamp to search for scratches and foreign bodies in the cornea.

Physicians often use the wood lamp to examine for fungal, bacterial, and parasitic infections. The Wood lamp is safe and does not damage the skin or cause sunburn. The examination is usually very brief and unlikely to cause harm even in light-sensitive individuals. The recommendation is for patients to close their eyes when during exposure to a Wood’s lamp.