Astigmatism Correction With Contact Lenses
Astigmatism
Astigmatism is a refractive error that is fairly common to some extent in just about everyone. The shape of your eye is normally like a sphere with curvature similar in all directions, but for some of us, that is not the case.
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Oblong or football-shaped corneas (front of your eye) cause a refractive error known as astigmatism. The corneal curvature in the horizontal meridian is different from that in the vertical meridian. If we trace the rays of light entering the eye, we find two focal points that do not fall on the retina (macula). The correction is simple with lenses to focus on those two main meridians.
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If the corneal Astigmatism is low, it is better corrected with RGP spherical lenses, which will mask the corneal astigmatism with the tear film. If the corneal astigmatism is high, a bitoric RGP lens may be needed to correct what cannot be masked with the tear film.
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Besides corneal astigmatism, there is internal astigmatism, usually caused by the misshape of your eyes' internal structures, such as the crystalline lens. A soft toric lens will easily correct this type of astigmatism.
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Finally, your astigmatism could be mixed, with part internal and part external. Special soft lenses will correct this type of astigmatism.
Our Optometrist Can Correct Astigmatism!
Large eyes that have football-shaped corneas have astigmatism, known as myopic astigmatism, and small eyes that are football-shaped have astigmatism, known as hyperopic astigmatism. The eye may have a shape that has both types of astigmatism, known as compound astigmatism. Finally, there is one more type of astigmatism known as irregular astigmatism which is a distortion of some form normally in the cornea.