Refractive error icon

REFRACTIVE
ERRORS

Refractive errors deal with a variety of conditions that distort vision.

Anatomy image showing light passing through the structures of the eye

Refractive errors are when the cornea is abnormally shaped and can’t focus light directly on the retina at the back of the eye, resulting in out-of-focus and blurry vision. 

Conditions include short-sightedness (myopia), far-sightedness (hyperopia), astigmatism and age-related long-sightedness (presbyopia).

What are the types of refractive errors?

Short-sightedness (Myopia)

Difficulty in seeing longer distances.

Long-sightedness (Hyperopia)

Difficulty seeing things up close. If you are over 40, you may in fact have Presbyopia.

Astigmatism

A blurry portion of vision. Astigmatism commonly occurs together with short or long-sightedness.

Presbyopia

Also known as age-related long-sightedness, this is caused by reduced flexibility in the lens of the eye usually occurring after age 40.

What are the causes of refractive errors?

Refractive errors are typically genetic although short-sightedness can be caused by environmental factors such as excessive eye strain from continued focus on a computer screen, TV or book.

Age related long-sightedness is due to a hardening of the lens caused by age. Astigmatism can occur from an eye injury but is also, and primarily, a genetic condition.

What are the symptoms of refractive errors?

Apart from the obvious definitions above, some people are not aware that they may have a refractive issue, particularly if they have had it all their life or it occurs gradually. The following symptoms may indicative a refractive issue:

What are the treatment options for refractive errors?

Refractive errors of varying degrees are very common in the population. The following treatment options include:

Glasses and contact lenses

The main non-surgical solutions to refractive errors.

Laser Eye Surgery

These procedures alter the shape of the cornea so the light is focused correctly on the retina. Three generations of laser eye surgery are available including SMILE, LASIK and PRK.

Lens replacement

Used in aged-related long-sightedness (Presbyopia) or when laser surgery isn’t possible.

Implantable Contact Lens (ICL)

Inserted between the iris and the lens. This is used when laser eye surgery is not possible due to thin corneas or the strength of prescription is too high.

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