What is astigmatism?
Some people are born with astigmatism in the cornea of the eye – the transparent membrane that covers the front of the eye. Astigmatism is an irregular curvature of the cornea or the lens, and this causes visual disturbances. When the curvature of the cornea or the eye lens varies in different directions, vision in some directions will be sharper than in other directions. For this reason, this irregular curvature causes blurred vision, regardless of the person looking at objects close to or far from the eye. Astigmatism can occur with other visual disturbances, herein long-sightedness or short-sightedness.
What are the symptoms of astigmatism?
Astigmatism is characterised by symptoms such as:
Blurred vision in both vertical, horizontal or diagonal lines and in all distances from the eye
Pinching your eyes to see more clearly
Reading causing tiredness
Feeling double vision, especially in the evening
What are the causes of astigmatism?
Astigmatisms are usually hereditary structural changes of the cornea or the lens and are very frequent, as tiny irregularities are the cause of the condition. Astigmatism can be inherited from your parents, but it can also be a result of an injury or disease in the eye or following an eye operation. Astigmatism is diagnosed by an optician or an eye doctor.
What are the treatments for astigmatism?
Depending on the degree of astigmatism, the condition can be treated in different ways. In some cases, the astigmatism is so small that no treatment is required. Glasses and contact lenses can be used to correct astigmatisms in both the cornea and the lens but only on one level, which could be the horizontal level. Furthermore, some contact lenses are only used in special cases of astigmatism. These are called ‘Ortho-k-lenses’, and they cause the irregular curvature of the cornea to correct itself into place. These contact lenses are hard and must be used several hours a day to maintain the achieved, correct curvature.
It is also possible to undergo an eye operation that can correct the structure of the eye. The method is called ‘LASIK’. The eye specialist makes a tiny flap superficially on the cornea, which is lifted aside, and afterwards the cornea is treated with laser to level the curvature of the cornea to ensure that the refraction of light becomes unidirectional. However, the operation involves a risk of complications such as dry eyes or blurred night vision.