The video game Tetris could fix lazy eye, according to a new study.

Lazy eye, also known as amblyopia, is a common eye disorder. Research done by Dr. Robert Hess from McGill University Health Centre, Montreal, says the fun video game could be used to train the eyes to work together.

Lazy eye is a common visual impairment in which one eye is significantly weaker than the other.  If caught in childhood, lazy eye can be treated by wearing corrective glasses and wearing an eye patch over the stronger eye for several hours a say. According to the National Institutes of Health, amblyopia affects approximately two to three out of every 100 children.

In his study, Hess took 18 adults with the condition and had them wear head-mounted video goggles that displayed the Tetris game. To mimic the condition of lazy eye, the goggles displayed the game separately for each eye so one eye could see the falling Tetris blocks and the other only the ones already on the ground.

Hess and his team found half of the participants played the game by combining information from both eyes, and the other half played the game only with the weaker eye. The findings showed great improvement in vision of the weaker eye, as well as improvement of depth perception in the group as a whole.

"The key to improving vision for adults, who currently have no other treatment options, was to set up conditions that would enable the two eyes to cooperate for the first time in a given task."

When we get the two eyes working together, we find the vision improves. It's much better than patching, much more enjoyable, it's faster and it seems to work better," Hess told BBC News.

The research was published in the journal Current Biology. Researchers say they hope to begin testing the video game therapy on younger patients.