What is an astigmatism?
Astigmatism is a common visual defect. Astigmatics corneas or eye lenses have a dome that causes light entering the eye to break in the wrong way. The light does not break down to a sharp point on the retina, regardless of whether you are looking in the short or long range. The result is a blurred vision that can be very strenuous to the eyes. Astigmatism is also almost always combined with either oversight or myopia.
Fortunately, there is help to get at a licensed optician. Glass for astigmatic correction is called cylinder glass and the contact lenses are called toric lenses.
Causes
To be able to look sharply, light entering the eye needs to be focused on the same point. Then it is important that the cornea or eye lens is round, like a football, so that the light should be broken in the same way no matter where it comes from. The curvature bends the light so that it focuses precisely on the retina, on the back of the eye.
If you have astigmatism, however, the surface of the lens is unevenly shaped and the light does not break correctly. The light is not focused on a point on the retina and the result is blurred or distorted vision.
This irregular curvature can be hereditary, caused by a disorder of the eye’s development or can sometimes develop after eye damage or eye surgery.
The lens curvature in the eye may change over time, resulting in an increase or decrease in astigmatism. This change often occurs in adulthood and may precede the development of naturally occurring cataracts.
Symptoms
Impaired visual acuity
Your field of view and objects in your surroundings become blurred. It is very strenuous for the eyes to get an object in focus.
Headache and dizziness
Astigmatism is often followed by headache or dizziness. For example, if you are sitting in front of a computer screen for a long time, it is not uncommon for your eyes to get tired, especially if you need a peep to see clearly. The problem with astigmatism is that the vision system is under constant load. Our brains and vision systems do not like blurred vision and therefore do their best to correct the error, without succeeding. This gives rise to an eye strain which in turn can lead to severe headache or dizziness.
Glasses and contact lenses
Since astigmatism arises from uneven distribution of light rays, it is corrected when light rays can be broken so that the light is focused on the retina. If you have astigmatism, you have a wide range of options to correct your vision problem. In consultation with your optician, you can choose the solution to best suit your needs.
Glasses
The glasses contain so-called cylinder glasses that compensate for astigmatism. This glass provides extra power in specific parts of the lens to make sure the light breaks properly in the eyes.
Contact lenses
Toric contact lenses are usually prescribed for people with astigmatism. Toric lenses correct the refractive error by being bent at different angles, adapted to your eye.
People who also have presbyopia, a natural vision defect that usually occurs in their 40s, may need progressive lenses (also called bifocal lenses).