What Does the Doctor Look For?
With sophisticated research tools, 20/20 vision has been documented in toddlers, once the shape and size of their eyeballs have fully matured. However, measuring sight with an eye chart depends on communication skills and cooperation, so your pediatrician won't be able to test for visual acuity until your child is at least 3 years old.
In the meantime, your pediatrician will closely examine your baby's eyes for problems, starting from birth. She'll check both the physical shape and size of the eyes and eyelids. And although newborns don't want to open their eyes to bright light, she'll use the light from an ophthalmoscope to check for the "red reflex," a reassuring red color that is reflected off the back of a baby's eyes, giving them a red glow. If this is absent, it could indicate the presence of a cataract, glaucoma, or a congenital eye defect. She'll also look for common problems, such as blocked tear ducts. If your child was premature or if there is a family history of congenital eye problems, the pediatrician will recommend that your baby be examined by a pediatric ophthalmologist in the nursery or soon after discharge.
In addition, at each well-child visit you'll see your baby's doctor dangling an object over her face to see how well she "tracks" it 180 degrees. And to make sure her eye muscles aren't weak, the doctor will shine a light at her eyes, checking that the reflection is at corresponding locations on each pupil.
What Should I Look For?
Before 6 months, it's common for a baby's eyes to appear "crossed," but after 6 months his eyes should begin to work together to focus on an object. If you notice one of baby's eyes drifting off to the side, especially when he is tired, call your pediatrician and let her know. Other signs of vision problems are tilting his head to see an object or bringing it very close to his eyes, sensitivity to light, chronic redness, and tearing. Older kids may complain of headaches.