Although possible, being both farsighted and nearsighted is rare. It is more likely for a person to be either farsighted or nearsighted.
When a person is farsighted, objects farther away appear clearly, while nearby objects are blurry or difficult to make out. A nearsighted person can see objects close by clearly, but far away objects appear blurry.
A condition known as anisometropia can cause simultaneous far and nearsightedness. This condition causes one eye to have different focal points compared to the other eye.
This article outlines the symptoms, causes, and treatments for simultaneous far- and nearsightedness.
Anisometropia is a condition where one eye has different refractive power than the other. This leads people to experience unequal focus between the two eyes without glasses or corrective lenses.
People with this condition will notice blurry vision in one eye compared to the other. The brain will be unable to receive information from both eyes. Instead, it will pick the eye that has the clearest focus.
Anisometropia is one of the leading causes of amblyopia in children. Amblyopia is the medical term for what some people call “lazy eye.” Often, one eye will get increasingly blurry while the brain relies on the other for clear vision.
Amblyopia is the
- a squint
- shutting one eye
- tilting the head
In severe cases, a child’s eye may drift or wander.
The cause of anisometropia is likely due to a difference in the size or shape of the eyes. This can cause:
- unequal curving, known as astigmatism
- unequal farsightedness
- unequal nearsightedness
The condition is the cause of about 30–50% of all cases of lazy eye, which affects about 2–4% of people living in North America.
In older people, changes in lens power and cataracts
Eye doctor visits or vision screenings at school can typically easily identify anisometropia in children and adults.
Treatment for anisometropia often involves using glasses or contacts to correct the vision in the weaker eye. This can help the brain learn to use both eyes together.
Sometimes, a child may need additional help getting the brain to use the weaker eye. A doctor may recommend:
- patching the dominant eye
- using a filter on the glasses over the dominant eye
- using eye drops to make the dominant eye’s vision blurry
A child’s vision often changes over time. However, the difference in focus between the two eyes can remain. Early treatment can help improve outcomes.
The following are answers to questions people commonly ask about being nearsighted and farsighted.
What is it called when a person is nearsighted and farsighted?
If a person has both nearsighted and farsighted vision, it typically means they have anisometropia.
This condition causes one eye to see differently than the other. It can cause the brain to choose one eye over the other, leading to the development of a dominant eye.
Is antimetropia rare?
Yes. Antimetropia is a rare subtype of anisometropia that involves nearsightedness in one eye and farsightedness in the other.
How rare is anisometropia?
A person can be farsighted and nearsighted. This typically manifests as a condition known as anisometropia, when one eye’s focus is different from that of the other eye.
It can mean their vision is blurry in one and acute in the other. The brain then selects a dominant eye to see out of.
Treatment often involves using corrective lenses. With early treatment, some children who develop the condition will outgrow it.