Beginning in April 2009, McCann was bothered by blurry vision in his left eye, due to a slight vision change following 2007 LASIK surgery. He decided to opt for glasses when contact lenses proved uncomfortable. In May 2009, Oakley, Inc. made special glasses for McCann to correct the vision problem and allow for comfort under the catcher's mask. McCann remarked, "I need my Oakleys. I have to have the wraparounds for my peripheral vision." In 2009, he had more errors at catcher than any other major leaguer, with 12, and had the lowest fielding percentage among them (.988).