Which are the various types of Refractive Errors?
What is Myopia (Nearsightedness)?
Nearsightedness or myopia is a condition in which near objects are seen clearly, but not distant objects. This occurs because the light rays focus in front of the retina due to either longer eye ball or increased corneal curvature of a steep cornea. The more myopic you are the blurrier is your distant vision, and objects will have to be brought closer to see clearly.
It can be corrected by prescribing eyeglasses or contact lenses.
Symptoms
- Blurry vision for distant objects
- Eyestrain
- Headaches
- Difficulty seeing the board or screen
What is Hyperopia (Farsightedness)?
Farsightedness, or hyperopia is a condition in which distant objects are usually seen clearly, but close ones are not clear. Farsightedness occurs if your eyeball is shorter than the normal or the cornea is less curved than normal or flat, so light entering your eye is focused behind the retina. A newborn is initially hyperopic and with age the eye grows to normalcy.
In mild cases of hyperopia, patient may not need corrective glasses, as eyes may be able to compensate. In other cases, the ophthalmologist may prescribe spectacle or contact lenses to optically correct this condition or to treat aesthenopic symptoms of the patient.
Symptoms
- Blurred vision for close objects
- Eyestrain
- Difficulty reading
- Eye discomfort
What is Astigmatism (Distorted Vision)?
Astigmatism is a condition where the front surface of your eye, the cornea, is irregular in shape preventing the light to focus at one point on the retina. As a result, the vision would be blurred at all distances. Astigmatism rarely occurs alone. It is usually accompanies myopia or hyperopia.
Most of astigmatism can be corrected with properly prescribed and fitted eyeglasses and/or contact lenses. However, higher astigmatism may be better handled by surgical means.
Symptoms
- Blurred or distorted vision
- Aesthenopic symptoms like headche
- Squinting