Ashley Roos was shot in the eye with a paintball gun as she stood at a bus stop in Ottawa in 2007. (CBC)

Getting hit with a paintball can cause severe and devastating eye injuries, especially when goggles aren't worn, say ophthalmologists, who add that informal games are when damage is more likely.

High-velocity paintballs can cause tremendous damage to the eye and can lead to surgery, Dr. Kyle Alliman of Bascom Palmer Eye Institute at the University of Miami Miller School of Medicine said.

"Unfortunately, visual loss is often permanent."

In the February issue of the American Journal of Ophthalmology, Alliman and his colleagues reviewed 36 cases of paintball injuries to the eye that were treated at the institute between 1988 and 2005.

In 28 per cent of the patients, the eyeball was ruptured, and in 19 per cent, the retina detached.

Surgery was required in 81 per cent of the patients, including eventual removal of the eye in 22 per cent, the researchers said.

Vision was restored to near normal levels of 20/40 or better in 36 per cent of the patients, who were mostly men with an average age of 21.

Organizers of formal paintball games require eye protection and education, which has reduced the risk of severe injuries.

The results suggest eye injuries are more likely to occur when paintball is played in informal settings, the researchers said.

"Eye protection can prevent over 97 per cent of injuries," Alliman said.