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Movies like "Alice in Wonderland" and "Avatar," which are available to view in 3-D, may be shattering box office records – but could they be shattering your eyesight as well?

Some people have reported having headaches and/or feeling sick after watching these flicks, so we posed the question to Dr. Mike Ehrenhaus, an ophthalmologist based in Queens and Brooklyn, N.Y.

An average person with good eyesight and healthy eyes should not have any trouble watching a 3-D movie – even for a lengthy period of time, Ehrenhaus said.

However, there are two types of people who may not be able to watch movies featuring this technology, he noted.

The first type of person is someone who suffers from amblyopia, or a lazy eye, Ehrenhaus said.

"If your eyes are weak, and you have a lazy eye, you could be getting a little bit of a filter," he said. "You may feel some eye strain, which could cause a headache."

And those who have poor vision and are either not wearing their glasses inside the movie or don’t have an updated prescription may have depth perception problems when watching a 3-D movie – especially if one eye has worse vision than the other, he said.

"These people would be straining their eye to focus and that can definitely give you a headache," Ehrenhaus said.

According to the electronics industry newsletter EETimes.com, researchers are studying a convergence-accommodation conflict that can occur while watching 3-D movies.

With a convergence-accommodation conflict, the person has to adjust his eyesight to moving images while still keeping focused on the background – and this can cause a sensory conflict.

Ehrenhaus said he has not heard of this being a major problem.

"If anything, 3-D technology is positive," he said. "We are using virtual reality 3-D methods in surgeries, and it’s fantastic. It works really well, and it’s not harmful."

If you fall into any of above categories, save a few extra bucks, and opt for the non 3-D version instead. After all, movies are supposed to be all about the story line.