Can increased digital usage cause long-term vision damage?

From smartphones to tablets, more people are spending more time looking at digital screens but could this be causing damage to your vision?

"I'm on twitter first thing in the morning," said Kate Marlys.

As the owner of Philly PR Girl, Marlys spends a lot of time looking at digital screens.

"I'm always on my computer and iPad and monitoring social media so it's really all day, every day," said Marlys.

And she's not alone. In fact, a recent report found the average American spends about seven hours a day staring at screens.

Those screens emit what's called high-energy visible light also known as "blue light."

Dr. Brandon Ayres, an ophthalmologist at Wills Eye Institute, says we know staring at screens can cause problems in the short-term.

It's called Computer Vision Syndrome. Your vision can get blurry, your eyes can get red, feel dry and irritated.

"They feel that strain around their eyes and they're squeezing their eyes trying to blink, trying to get their vision to come back," said Dr. Ayres.

"I always have eye drops with me. That's my trick," said Marlys.

The dryness is mostly due to positioning. If you look straight, your eyes are more open and when you concentrate, you blink less.

Rest your eyes and they should feel better.

But what about damage in the future?

Some studies done in animals show blue light can cause damage to the retina.

That damage looks like macular degeneration - the leading cause of permanent vision loss.

But Dr. Ayres says while there is concern, at this point, we just don't know the impact it will have on people.

"We really don't know what's going to happen in five or 10 or 15 years. So far, I'd have to say we're not seeing any long-term effects. We're not doing more surgery because patients are using PDAs or computers all day long but I can't look into the future," said Dr. Ayres.

For now, he does recommend simple changes to at least prevent eye strain.

Position your computer monitor at least an arm's length away from your eyes.

And slightly lower the screen. By looking down your eye lid will protect more of your eye.

Use artificial tears for dry eyes, lower the brightness on your devices and take breaks.

"Make sure every 10 to 20 minutes, you're taking a break, look across the room, let the eyes relax," said Dr. Ayres.

Some other tips from Dr. Lori Grover, Dean of College of Optometry at Salus University in Elkins Park:

Chronic computer eyestrain may benefit from computer vision eyeglasses, especially toward end of the day.

She says many of the new materials in glasses have UV coatings, and they can protect a little from blue light.

Practice the 20-20-20 rule for breaks which means every 20 minutes, look 20 feet in the distance for at least 20 seconds.

For more information:

-Computer Vision Syndrome: Causes, Diagnosis, Treatment

-Computer Vision Syndrome Symptoms

-The Relationship of Computer Vision Syndrome to Musculoskeletal Disorders

-Computer Vision Syndrome and Computer Glasses FAQ

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