Astigmatism (uh-STIG-muh-tiz-um) is a typical and normally treatable imperfection in the curvature of your eye that causes blurred range and near vision. But what can affect to your astigmatism getting worse?
Astigmatism occurs when either the front surface area of your eye (cornea) or the lens, inside your eye, has mismatched curves. Instead of having one curve like a round ball, the surface area is egg shaped. This causes blurred vision at all distances.
Astigmatism is often present at birth and might take place in combination with nearsightedness or farsightedness. Frequently it’s not noticable adequate to require corrective action. When it is, your treatment alternatives are restorative lenses or surgery.
Your eye has two structures with curved surfaces that flex (refract) light onto the retina, that makes the images:
- The cornea, the clear front surface area of your eye along with the tear film
- The lens, a clear structure inside your eye that modifications shape to help focus on near objects
In a perfectly shaped eye, each of these elements has a round curvature, like the surface area of a smooth ball. A cornea and lens with such curvature bend (refract) all inbound light to make a sharply focused image directly on the retina, at the back of your eye.
A refractive error
If either your cornea or lens is egg formed with two mismatched curves, light rays aren’t bent properly, causing a refractive error. This makes a blurry image. Astigmatism is a type of refractive error.
Astigmatism takes place when your cornea or lens is curved more steeply in one direction than in another. You have corneal astigmatism if your cornea has actually mismatched curves. You have lenticular astigmatism if your lens has actually mismatched curves.
Either kind of astigmatism can cause blurred vision. Blurred vision may occur more in one instructions, either horizontally, vertically or diagonally.
Astigmatism might exist from birth, or it might develop after an eye injury, disease or surgery. Astigmatism isn’t triggered or intensified by checking out in poor light, sitting too close to the tv or squinting.
Other refractive errors
Astigmatism may take place in combination with other refractive errors, that include:
- Nearsightedness (myopia). This occurs when your cornea is curved excessive or your eye is longer than normal. Instead of being focused precisely on your retina, light is focused in front of your retina, making remote items seem blurry.
- Farsightedness (hyperopia). This occurs when your cornea is curved too little or your eye is much shorter than normal. The result is the opposite of nearsightedness. When your eye remains in an unwinded state, light never ever concerns a concentrate on the back of your eye, making nearby objects seem blurry.
Often, astigmatism can develop after an eye disease, eye injury or surgery. It is a myth that astigmatism can develop or intensify from reading in low light or sitting really near to the television.