February 25, 2010 (CHICAGO) -- Digital technology is making the 3-D experience like nothing before. But many people still say trying to see in stereo leaves them with a headache, stomach ache or both. That could be a sign of an undiagnosed vision problem. And there may be a way to fix it.
For decades, 3-D was seen as more of a gimmick than an art form. Today's three-dimensional experience is challenging that perception. And by spring you could have a 3D TV in your home.
But even in this advanced form3-D is leaving some viewers feeling sick. Angela Brusnman is one of them.
"Throughout the experience it's definitely an ocular headache. You can tell it's definitely coming from right behind the eyes," said Brunsman.
Complaints include headache, nausea, dizziness and fatigue. There are no hard numbers but its estimated anywhere from 4 to 10 percent of the population can't watch or tolerate 3-D.
"Anywhere from 3 million to 9 million or more will have binocular vision dysfunctions that will stop them from enjoying 3-D movies," said Dominick Maino, O.D., optometrist, Illinois Eye Institute.
So what does that mean?
Three-dimensional film requires each eye to see a different image at the same time. Many people may have minor vision problems that aren't evident on a day-to-day basis. Watching 3-D may unmask the issues. They include things such as lazy eye or convergence insufficiency which means the eyes are not turning in properly to focus. During a 3-D movie, if focusing isn't spot on, you can experience problems.
"It's actually something you can do something about," said Maino.
Maino says these problems can be fixed with vision training, something he does at the Illinois Eye Institute.
"We teach someone how to get those eyes coordinated moving together and then do a neuro-imprint so the brain remembers how to do this in the future," said Maino.
Shannon Wyatt, 28, says her headache started one hour into the 3-D version of Avatar.
"Your brain is totally ignoring the input from one of your eyes," said Wyatt.
Wyatt has been diagnosed with convergence insufficiency. She thinks this may also explain why she sometimes gets tired when reading or gets dizzy talking with people close up.
"The therapy we did try was pretty impressive, how different it felt inside my head," said Wyatt.
But not everyone is convinced.
UIC Eye & Ear Infirmary ophthalmologist Dimitri Azar says it's important to seek an eye exam if you are having daily vision problems. But has his doubts about vision therapy.
"Scientific evidence to support the fact that you could re-train an adult to be able to regain 3D vision is not very strong. But there are some individuals who report that their ability to see 3D has improved," said Azar.
Some experts are starting to question what 3-D could be doing to normal eyesight.
Research from the University of California Berkeley claims poorly made 3-D movies may cause eye strain and fatigue because the eyes have to work so hard.
"That is probably more problematic for young adults, teenagers, etc," said Martin Banks, PhD., UC Berkeley Optometry.
Three-dimensional experts say the newer digital technology does address several of the problems that caused 3-D moviegoers discomfort in the past. And it is now easier to watch for many people.