If you are near-sighted, far-sighted, or have astigmatism, refractive surgery may correct or improve your vision. In some cases, refractive surgery may be able to help presbyopia. There are various surgical procedures for correcting or adjusting your eye's focusing ability by reshaping the cornea, the clear outer layer at the front of your eye. Other procedures involve implanting a lens inside your eye. The most widely performed type of refractive surgery is LASIK (laser-assisted in situ keratomileusis), where a laser is used to reshape the cornea.

For most people, refractive surgery helps to reduce their dependency on glasses and contact lens and enables them to lead an active lifestyle.

Types of refractive errors

There are four different types of refractive errors and they are:

1. Myopia (Short-sightedness or Near-sightedness)

Myopia (short-sightedness or near-sightedness) is a condition in which a person is able to see near objects well (when reading a book or working on the computer) but has difficulty seeing objects that are far away (road signs or bus numbers). Myopia occurs when the eye is unable to focus light rays accurately on the seeing part of the eye, the retina.

2. Hyperopia

Hyperopia (long-sightedness or far-sightedness) occurs when a person can see objects far away but may experience problems seeing up-close objects clearly. Like other refractive errors, hyperopia occurs when the eye is unable to focus light rays accurately on the seeing part of the eye – the retina.

3. Astigmatism

Astigmatism is a condition where the cornea has an abnormal curvature, causing a distortion in vision. A normal cornea is shaped like a sphere but in astigmatism the cornea is oval-shaped, causing problems in focusing the light entering the eye. Astigmatism is a common condition and often occurs together with myopia (short-sightedness) or hyperopia (long-sightedness).

4. Presbyopia

Presbyopia (Lao hua) is an age-related condition in which a person is unable to focus on near objects. Presbyopia is a normal natural ageing process of the eye and usually begins at around 40 years old.

Click on the links below to learn more about the different refractive surgery procedures that are available currently.

Are you a Good Candidate for LASIK?

LASIK Surgery: Is It Right For You?

Common LASIK Myths Debunked

All about LASIK – Doctor Q&A

LASIK / ReLEX – Doctor Q&A

About LASIK – Doctor Q&A


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Ref: L20