Eye Disease/Disorder – Refractive Error

A Refractive Error is a very common eye disorder. It occurs when the eye cannot clearly focus the images from the outside world. The result of refractive errors is blurred vision, which is sometimes so severe that it causes visual impairment. Refractive errors are disorders, not diseases. A Refractive Error means that the shape of your eye does not bend light correctly, resulting in a blurred image. Light has to be refracted or bent by the cornea and the lens to the retina in order for us to see.

The following are the most common Refractive Errors, all of which affect vision and may require corrective lenses or surgery for correction or improvement:

Astigmatism (blurred vision at all distances)
Astigmatism

Astigmatism is a condition in which an abnormal curvature of the Cornea can cause two focal points to fall in two different locations – making objects up close and at a distance appear blurry. Astigmatisms may cause eye strain and may be combined with nearsightedness or farsightedness. Eyeglasses, Contact Lenses, or Corrective Surgery may help to correct or improve the condition.
Hyperopia (close objects are blurry).
Hyperopia

Commonly known as farsightedness, hyperopia is the most common refractive error in which an image of a distant object becomes focused behind the retina, either because the eyeball axis is too short, or because the refractive power of the eye is too weak. This condition makes close objects appear out of focus and may cause headaches and/or eye strain. Eyeglasses or contact lenses may help to correct or improve hyperopia by adjusting the focusing power to the Retina. Corrective surgery may also help by changing the shape of the Cornea to a more spherical, round shape instead of an oval shape.
Myopia (distant objects are blurry).
Myopia

Commonly known as Nearsightedness, Myopia is a condition in which, opposite of hyperopia, an image of a distant object becomes focused in front the retina, either because the eyeball axis is too long, or because the refractive power of the eye is too strong. This condition makes distant objects appear out of focus and may cause headaches and/or eye strain.

Presbyopia (aging of the lens in the eye).
Presbyopia

After age 40, the lens of the eye becomes more rigid and does not flex as easily. The result is that it is more difficult to read at close range. This normal aging process of the lens can also be combined with myopia, hyperopia or astigmatism. Presbyopia is commonly treated using corrective lenses, such as eyeglasses or contact lenses.

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