From episode 158 on the Medicine Feed. With Dr. Nellie Choi.
I’d kinda given up on Wood’s lamps when hunting for ringworm. I’ve taken hundreds of concerned cats with skin lesions into a dark room with my little portable UV light, with pretty much zero success in finding ‘apple green’ fluorescence.
Dermatologist Nellie Choi says that’s because that little portable UV light isn’t actually a Wood’s lamp!
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A Wood’s lamp and a standard UV light / black light are 2 totally different things. They have very different wavelengths, and the Woods’ wavelength is essential to get the fluorescence of dermatophytes.
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Your little portable black light isn’t much good for anything except checking if your bank notes are counterfeit. (Although I did learn that scorpions fluoresce beautifully - kinda apple-green actually - under a UV light on our recent trip to South Africa!)
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If you’re not sure whether you have the real deal, a pretty good guide is that most good quality genuine Wood’s lamps plug into the wall.
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