A 26-year-old man from China suffered a detached retina after hours of texting his girlfriend in the dark, using his cell phone messaging app, WeChat. He was required to undergo emergency surgery after his eyesight became plagued with sudden flashes and he discovered his left eye’s retina had become detached.

Retinal detachment — which is normally more prevalent among older people — has become increasingly more common in young people due to excessive cell phone use. The retina is a light-sensitive layer of tissue inside the eye, which sends messages through the optic nerve to the brain. A detached retina involves it being pulled from its normal position; if it’s not treated, this condition can cause permanent vision loss. A retinal detachment is considered a medical emergency.

The Chinese man had reportedly been texting his girlfriend nonstop throughout the day and several hours at night in bed, which spurred his retinal detachment. Yu Bin, an eye expert, told WantChina Times that this was an extreme case, but that it was indeed possible for people to mess up their vision from excessive cell phone use — whether it’s retinal detachment, conjunctivitis (pinkeye), or keratitis (inflammation of the cornea).

In addition, some scientists believe that eye strain can occur from staring at devices: “Our eyes have evolved for three-dimensional viewing,” Andrea Thau, a New York City-based optometrist who is also part of the American Optometric Association, told NBC News, “so we wind up overfocusing as we strain to find a 3-D image on a close-up 2-D screen.” Though there have been some studies that warn of phone and tablet use endangering your eyesight, it’s probably safe to assume that unless you’re excessively staring at your screen for hours at a time, your eyes will probably be okay.