Obstructive sleep apnea (breathing pauses during sleep) may increase the risk of vision-robbing glaucoma by about 67%. Researchers from Japan's Hokkaido University say sleep apnea may damage the optic nerve, which carries signals from the eyes to the brain, by reducing oxygen in the bloodstream. Treating sleep apnea could help manage glaucoma and, for those who already have the condition, keep vision from worsening.