What is Contact Lenses Astigmatism?

If you find that images sometimes blur, regardless of the distance they are at, then you should see an optician as you may have what is known as astigmatism. Astigmatism is one of a group of eye problems that specialists call refractive errors. All that astigmatism really means is that you have a variation in the shape of your cornea.

Errors like astigmatism cause a disturbance in the way that the eye deals with rays of light. In most people the corneal surface is smooth but with astigmatism there is an irregular curve in the cornea. Because the irregular curvature the eye cannot deal properly with light refractions and so images are always slightly blurred, no matter how near or far away they are. It used to be thought that if you had an astigmatism then you would not be able to wear contact lenses because in the past it was difficult to get a lens shape that would give the wearer optimum vision.

People with astigmatism can wear contact lenses, but they have to do so in consultation with their ophthalmologist because only certain contact lenses will work with astigmatism. There are special tonic lenses that are designed to work with and help correct astigmatism. Tonic contact lenses are made from the same materials as spherical lenses but unlike the spherical lens, they have two different powers in the lens. It used to said that people with astigmatism could not wear soft lenses, but modern soft lenses are very different and the proper soft lenses can work well with astigmatism.

There are certain tonic lenses now on the market that match the shape of the lenses with your blink. When you blink it works with the lens to stop it from rotating and keep it in the proper position so that you get optimum vision. Tonic lenses are multi or varifocal and come in a variety of colours besides the plain ones. They have greater light bending power in one axis than in others and it is this power that corrects the refractory error. These are disposable lenses that have to be changed every week or two.

There are two categories in astigmatism contact lenses and they differ by their power, with one of them being designed purely for astigmatism. These lenses have a special mechanism that stabilises the lens against your eyelid. Astigmatism contact lenses and tonic lenses are more expensive than normal contact lenses because of their delicate and complex construction. Getting the perfect fit for your eye needs the hand of an experienced ophthalmologist and can take some time.

While it is possible to buy astigmatism contact lenses over the internet at a lower cost, your doctor may not advise it because of the careful fitting that is needed to get the right lens for your eyes. If you do decide to have astigmatism contact lenses then you need to ensure that you keep them scrupulously clean. Some people with astigmatism are also bothered by dry eye, but it is still possible to get lenses that are designed for that condition as well as the astigmatism.