Astigmatism is a common type of prescription and usually occurs alongside long or short sightedness.Take a look at this blog to find out more about the causes and symptoms of astigmatism.
What causes astigmatism?
Astigmatism occurs when the cornea or the lens is more curved in one direction than the other. You will often hear astigmatism being referred to as rugby ball shaped or oval shaped eyes. Due to the curve of the eye, when light passes through the cornea and lens it causes the light to focus at different points, therefore, letters such as “c” can look like “g” or “o”.
There are certain factors that can cause astigmatism:
- Birth – in the majority of instances astigmatism is natural and you can be born with it. It is more common in premature or babies with low birth weight. In younger children astigmatism can improve with age.
- Genetics: one of the most likely causes of astigmatism is that it has been inherited from your parents or grandparents.
- Age: As we age, the shape of our eyes and more specifically our lens can change, leading to astigmatism.
- Eye injuries or surgeries: Trauma to the eye or certain types of eye surgeries can cause astigmatism.
- Thickenining: The front of the eye, conjunctiva can thicken, as it thickens it can grow onto your cornea this is known as pterygium. It is usually caused by prolonged UV exposure, dusty environments etc.
- Keratoconus: This is a condition which causes high levels of astigmatism and occurs when the cornea becomes thin and changes into an irregular cone shape.
What are the symptoms of uncorrected astigmatism?
The most common symptoms of uncorrected astigmatism include blurred vision and this can happen at any distance. Some specific symptoms include:
- Whilst driving, you may need to squint when driving to read signs or see objects clearly
- At night car headlights and street lights can appear elongated or even a starburst effect making it difficult to see clearly
- Eyes may feel strained and uncomfortable when reading, using a computer or electronic device
- Headaches
How is an astigmatism diagnosed
Your Optometrist will be able to pick up whether you have astigmatism as part of your eye examination. As part of our eye testing process we have a number of prelimary checks including the auto refractor - a machine which provides an estimate of your prescription and measures the curvature of the front surface of your eye.
You will be asked to sit down in front of the auto refractor and to place your chin on the rest in front of you. You will then be asked to focus on an image within the machine and in a matter of seconds the machine will get an estimate of your prescription which will be transferred to your Optometrist.
The Optometrist will then double check this with a range of other equipment and place different lenses in front of your eye. Your Optometrist will also show you two different lenses and ask you which lenses provides more clarity in your vision, this process is complete once the image is clearer and you have optimum vision.
Find about more about what to expect during your eye test here.
How can glasses and contact lenses help?
Glasses designed for astigmatism are equipped with corrective cylindrical lenses that properly refract light onto the retina of your eye. These lenses are prescribed and calibrated to match the exact nature of your astigmatism, which may differ between your two eyes.
With proper calibration and fitting, glasses for astigmatism can provide sharp, clear vision, helping you to see the world more clearly and comfortably. By working with your optometrist to determine the best prescription for your specific astigmatism, you can get glasses that fit comfortably and help you see the world with greater clarity.
Toric contact lenses are also a great option to correct regular astigmatism, they are designed to fit the shape of eyes with astigmatism providing clarity in your vision. Toric lenses are a great option for people with an active lifestyle or prefer how they look or feel in the lenses.
When to see an optometrist
Make sure to pay us a visit if your eye symptoms detract from your enjoyment of activities or interfere with your ability to perform everyday tasks and driving. An optometrist can determine whether you have astigmatism and if so, to what degree. They can then advise you of your options to correct your vision.
Eye care at M&S Opticians
Astigmatism is a common type of prescription and it can be easily corrected with the right prescription and care. If you're experiencing symptoms of astigmatism, schedule an appointment with our experts to get a comprehensive eye test and learn more about how we can help you with your optical health.