Double Vision on One Eye for a 14-Year-Old

My son, who is 14 years old, started to experience double vision about 1 month ago. It happens only to his left eye, and only when he sees the distant objects, for example, traffic lights or poles in the distance. When an object gets closer (about 30 feet), double vision on that eye disappears. The symptom is the same no matter if he covers the other eye or not. He just had his regualar annual exam with a DO right before that symptom started, and the eye exam result was that his vision on both eyes were good, about 20/25 for both eyes, and no problem was found. Recently, he got eye infection on the same eye - red inside the lower eyelid, swollen, irritating for a few day. It healed and then came back ago a week ago. I'm not sure if double vision and first eye infection happened around the same time. Now, eye infection is getting better. But double vision still persists. Is this something that could be serious? What could be the possible cause(s) of this? Thanks very much for the help!

[John C Hagan III, MD, FACS, FAAO]

double vision does not come from one eye. It is two distinct images that occur with both eyes open and when one eye is shut it goes away.

"Double vision" from just one eye is called monocular diploplia but in fact that almost never happens and what the person sees out of one eye is called "ghosting".  It can be a sign of needing glasses, corneal disease, cataracts, macular disease.

I would suggest you see an Eye MD ophthalmologist perhaps a pediatric ophthalmologist.  Find one near you at www.aao.org

JCHMD