Anisometropia

Anisometropia is a significant difference in the prescription between the two eyes, which can affect comfort, binocular vision, and in children can lead to amblyopia if not corrected.

Common symptoms

Blurred vision in one eye, eye strain, headaches, difficulty with depth perception, and sometimes no symptoms at all if the brain ignores the blurrier eye.

Description

Anisometropia means the two eyes focus differently. One eye may be more short-sighted, long-sighted, or astigmatic than the other. Small differences are common, but larger differences can cause the brain to receive two very different images that are difficult to combine.

In children, significant anisometropia is an important cause of amblyopia, because the brain learns to ignore the blurrier eye. In adults, it can cause tiredness, headaches, and reduced depth perception, especially if one eye has become more short-sighted or long-sighted than the other over time.

Treatment involves correcting the prescription with glasses or contact lenses. Contact lenses are often better tolerated for larger differences because they avoid image size differences between the eyes. In children, glasses are usually combined with amblyopia treatment such as patching or atropine drops.