Toric Lenses: Best For Correcting Astigmatism
December 31st, 2009 | by admin |Astigmatism is condition where the patient experiences blurred vision due to the distortion of cornea. It causes the light rays to fall on the retina from a number of different angles, which makes the eye lose focus. The condition can be corrected by wearing Toric Lens.
Well, toric lens is not much different from an ordinary contact lens so far as the material it is made of is concerned. It is different in that its one or both sides of the optical surface work as a cylindrical lens often combining it with spherical lens effects. It may happen sometimes that only one eye has astigmatism while the other is perfectly alright. In such cases the patients are advised to wear a Toric lens in one eye and a normal vision correction lens in the other.
Toric lenses, though made of the same material as the ordinary contact lenses, are effective in correcting both the cylindrical as well as spherical aberrations. Being asymmetrical around the center, they should not be rotated. They are designed to remain unaffected by the movement of the eyes.
Toric lenses need to be custom fitted to suit your eyes and so they take a little longer to be checked and re-checked to make sure that your vision is effectively corrected by the lenses and that they fit you properly. It is then that you can leave the specialist’s clinic and go home with your lenses.
It is not necessary that only Toric lenses can correct astigmatism. If it happens to be of a lesser degree a normal lens can effectively mask it. However, a higher degree of astigmatism can only be corrected by a soft toric lens, rigid contacts or spectacles. One may go for either a soft or rigid contacts. Soft lenses have an edge over the rigid ones in terms of comfort and adaptability while the rigid lenses score better than soft lenses in durability. Besides, rigid lenses are also a little easier to take care of than the soft ones. Many users also feel that rigid lenses give a crispier vision compared to the soft lenses.
Another option that is sometimes explored is the gas permeable lenses. They do not have any ability to correct astigmatism but their inflexibility makes them reshape the eyes. This helps correct the vision in cases of mild astigmatism. However, for higher degree of astigmatism Toric lenses seem to be the best available option.
Ashish Jain
http://www.articlesbase.com/advice-articles/toric-lenses-best-for-correcting-astigmatism-85315.html
4 Responses to “Toric Lenses: Best For Correcting Astigmatism”
By darwkins on Dec 31, 2009 | Reply
line on toric (astigmatism-correcting) contact lenses?
I noticed a radial line on my toric (astigmatism-correcting) contact lenses, Acuvue Oasys for Astigmatism. Is this line supposed to be pointing superiorly if the lenses are placed correctly? Or is it supposed to be pointing laterally / medially / inferiorly, or is the direction of the line not related to the correct placement?
By Isa Bella on Jan 1, 2010 | Reply
You are so lucky I came by this section…
That is the same EXACT prescription I use!
Acuvue Oasys Astigmatism…. (with hydraclear plus)
When you take the contact out of the casing, use your fingers to gently place it on your index finger…. make sure the outer rim is a circle- not oval, and make sure the inner ring is flat against your finger, before insertion. The line goes like this / from in to out…..
The line is slightly visible, don’t worry about the line too much and focus on the directions I gave you…
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By B. Smith on Jan 1, 2010 | Reply
The line on your contact is related to the correct orientation of the contact on your eye. Your optometrist uses these "tic marks" to see if the contact has a tendency to sit on your eye at a certain orientation or if the contact is unstable and rotates constantly.
Different brands of contacts use different markings. Some use a single tic mark placed at 6 ‘o clock on the contact lens, some use 3 placed at 3, 6, and 9 ‘o clock, and others use 3 placed at 5, 6, and 7 ‘o clock. I’m not sure off the top of my head what Acuvue uses on their lenses.
Ideally, you would want to place the lenses in your eye in the correct orientation, but this really isn’t necessary. Contacts that correct for astigmatism are designed in such a way as to orient themselves correctly on the eye after a few minutes.
Hope this helps!
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I’m an optometry student
By Rico on Jan 1, 2010 | Reply
The line is the bottom of the lens. Its meant to help you insert them correctly, but doesn’t really make a difference as toric lenses are designed to rotate to the correct position. I use conventional lenses and have dots on mine.
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