Aneisometropia actually describes the vision when one eye has a very different prescription error to the other – usually when one eye is long and the other short sighted (for details of errors of vision see here).
Uncorrected Long Sighted Eye Uncorrected Short sighted eye
If you look through a friends glasses if they are short sighted their spectacle lenses will make the whole world look smaller.
If you look through those of someone who is long-sighted everything will look bigger.
When a person suffers with Aneisometropia this creates a big problem for the poor old brain because it has great difficulty putting the two pictures together to see just one of everything — at the least this means that vision through glasses is not just uncomfortable but usually means that the sufferer simply sees double!
Luckily there is one very simple way of solving the problem of Aneisometropia – Contact Lenses.
One of the biggest advantages of Contact Lenses is that, because they float right on the front of the cornea, they don’t enlarge or reduce the size of everything but focus a natural sized picture on the retina at the back of the eye.
As a result, by fitting Contact Lenses anyone with Aneisometropia will enjoy normal comfortable binocular vision, which would be impossible with glasses!