Late-night smartphone use may cause temporary blindness
Two women went temporarily blind after looking at their smartphones in bed. /Courtesy of Twitter
By Lee Jin-a
Two British women became temporarily blind while using their smartphones in the dark, according to a study published Thursday.
London-based researchers said that in unrelated events, the women were watching their phones while lying on their left side in bed and using only their right eye to watch the screen. A pillow covered their left eye.
Once the women put their phones down, their right eye, after it had adapted to the brightness of the screen, went blind until it had time to adjust.
The blindness disappeared when they looked at their phones again with both eyes while in the dark.
The longest period of blindness was about 15 minutes.
Researchers found the same effect when they deliberately re-created the conditions.
"People frequently use smartphones while lying down, when one eye can be inadvertently covered," said the study report, published in the New England Journal of Medicine.
"Hence, presentations such as we describe are likely to become more frequent. Our cases show that taking a detailed history, plus an understanding retinal physiology, can reassure both patient and doctor and can avoid unnecessary anxiety and costly investigations."