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Are you reading this on your smartphone? If you're lying down, you should keep both eyes open.
Two women experienced a shock when they lost sight in one eye after sneaking peeks at their smartphone in bed. Doctors dubbed the phenomenon “transient smartphone blindness.” It may sound like a cautionary tale about smartphone dangers, but it’s actually an easily avoidable condition.
“It’s really a temporary thing,” Dr. Rishi Singh, a staff surgeon at the Cole Eye Institute at Cleveland Clinic, who did not observe the women, told TODAY.
Both women experienced blindness lasting up to 20 minutes in only one eye, according to the report, published in the New England Journal of Medicine. They were reading on their phones in bed, with one eye closed in dimly light rooms. The bright light from the smartphone bleached the pigment in the opened eyes while the closed eyes didn’t get the exposure. When they opened the other eye and looked into the dim room, the bleached eye struggled to adjust while the closed eye acted normally.
It’s basically what happens after someone takes a photo with a bright flash.
“Because all the pigment is bleached, they cannot see. They thought they were blinded,” said Dr. Tongalp Tezel, Chang Family Professor of Ophthalmology at Columbia University.
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The researchers recreated the conditions in a lab — and the same thing occurred.
But Dr. Rahul Khurana, a spokesperson for the American Academy of Ophthalmology urges people not to worry too much.
For one thing, it's not an official medical condition. Also, more study is needed.
"It’s not what we would consider a serious problem,” he said via email.
But looking at smartphones can cause some eye problems:
- Staring at a phone can mean that people don’t blink enough, leading to dry eyes.
- People using small screens tend to squint, which leads to eye strain, and neck and facial spasms.
- The blue light from screens resets the circadian clock, which is the internal clock that regulates sleep/wake cycles.
- Disrupted circadian rhythms leads to poor sleep and contributes to obesity, hypertension, and diabetes among other conditions.
- Some link staring at smartphone screens to macular degeneration and cataracts, although Tezel is skeptical.
“There isn’t enough scientific data,” he said.
Not being able to see for up to 20 minutes may cause distress, but there is a super-easy way to avoid it: Keep both eyes open when checking smartphones in bed.
“I’m not sure this is a very common issue. No patients in my practice, which is in Silicon Valley, have ever come to me with these symptoms,” said Khurana.