Toric Contact Lenses...
What is a toric?
A toric contact lens is designed to correct astigmatism. With the latest toric
designs patients with high amounts of astigmatism can see 20/20 and enjoy comfortable
contact lens wear in soft lenses. In the past 5 years, many new toric designs
have become available. Many patients who were once told they had to wear a rigid
or hard contact lens can now be refit into the new soft toric contact lenses.
How do torics work?
Toric lenses correct vision on the eye in two directions at the same time. Most
contact lenses will spin from time to time while they are being worn. A toric
should not spin, or it will be correcting vision in the wrong direction. Even
a small amount of spin, or rotation, could cause blurred vision with a toric
lens. To solve this problem, torics are made thicker at the bottom edge of the
lens. Whenever the patient blinks, gravity pulls the thick edge of the toric
lens back down. This gives the toric lens the ability to recenter itself whenever
it rotates, allowing patients with astigmatism to enjoy clear vision with soft
contact lenses.
What is Astigmatism?
Astigmatism is a refractive vision problem. An astigmatic eye has two different
prescriptions in different directions at the same time. Astigmatism is not a
disease. Instead, the astigmatic eye is often described as being shaped oval
instead of round. If the astigmatic eye is oval, then a toric contact lens can
be considered an oval contact lens to match the oval shape of the eye.

Spherical Eye |

Astigmatic Eye |

Oblique Astigmatism |
The diagrams above demonstrate
how an eye can have more than one prescription, or power, at the
same time. The eye on the top left is spherical because it has
the same power in all meridians. The astigmatic eye on the top
right has a stronger power (-6.00) in the horizontal meridian than
in the vertical meridian (-3.00). The eye on the bottom also has
astigmatism, but it is oblique because the rotation is turned 45
degrees from the horizontal.
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