REFRACTIVE
ERRORS
Refractive errors deal with a variety of conditions that distort vision.
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.
Astigmatism
A blurry portion of vision. Astigmatism commonly occurs together with short or long-sightedness.
Age-related long-sightedness (Presbyopia)
Can develop from 40 years of age.
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:
- Double-vision
- Haziness
- Glare or halos around bright lights
- Squinting
- Headaches
- Eye strain
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 SMIE, LASIK and PRK.
Lens replacement
Used in aged-related long-sightedness 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.