What is astigmatism?
Astigmatism is a vision defect that makes images appear less sharp or slightly distorted, both up close and at a distance. It usually depends on the shape of the cornea, the transparent part at the front of the eye: instead of being uniformly curved like a ball, it is more curved in one direction, a bit like the back of a spoon. As a result, light is not focused on a single point and the image appears blurred.
What causes it?
In most cases, astigmatism is congenital and has a hereditary component: if someone in the family is astigmatic, it is more likely that you will be too. More rarely, it can appear after trauma or due to a corneal disease like keratoconus, which must be monitored by an ophthalmologist.
How to spot it
Typical signs are blurred vision, difficulty reading, tired eyes, and headaches after close-up work. You can do a preliminary test at home with this image:
Look at the "star" one eye at a time. If some lines appear darker or sharper than others, you may have astigmatism.
You can find a more complete version in our online astigmatism test. The test does not replace an eye exam: to know if you are astigmatic and to what degree, you need an eye exam. For your eye health, we recommend a visit to an ophthalmologist every year in any case.
Types of astigmatism
- Corneal astigmatism: due to the shape of the cornea. This is the most common type.
- Lenticular astigmatism: due to the crystalline lens, the natural lens inside the eye.
Can you be nearsighted and astigmatic at the same time?
Yes, it happens often: astigmatism can be accompanied by myopia (nearsightedness), hyperopia (farsightedness), or presbyopia. For this reason, the correction must always be custom-tailored.
How it is corrected
- Eyeglasses with lenses that correct the astigmatism in the right direction.
- Toric contact lenses, designed specifically for astigmatism.
In some cases, refractive surgery can be considered: if you are interested, talk to your ophthalmologist about it.
To learn more, read our guide on astigmatism and available solutions.