Astigmatism is a very common refractive error that can cause blurred or distorted vision at both distance and near.
It occurs when the eye does not focus light evenly onto the retina. Many people have some degree of astigmatism, and it can occur by itself or alongside myopia (short-sightedness) or hyperopia (long-sightedness).
Astigmatism is usually straightforward to correct with glasses or contact lenses.
What Is Astigmatism?
For clear vision, light needs to be focused accurately onto the retina at the back of the eye.
With astigmatism, differences in the curvature of the cornea, the clear front surface of the eye, or sometimes the lens inside the eye mean that light is focused differently in different directions.
Instead of producing one precise point of focus, the eye has more than one focal plane. This can make vision appear blurred, stretched, shadowed or distorted.
You may have heard astigmatism described as having an eye shaped like a “rugby ball rather than a soccer ball”. This can be a useful visual analogy, but astigmatism is really about differences in the eye's optical curvature rather than the whole eyeball literally being rugby-ball shaped.
What Does Astigmatism Look Like?
People with astigmatism can experience:
- Blurry vision at distance and/or near
- Letters or fine detail appearing shadowed
- “Ghosting” or double edges around objects
- Headlights or streetlights appearing streaked
- Glare and halos at night
- Difficulty seeing fine detail
- Squinting to sharpen vision
- Eyestrain or headaches
Symptoms vary depending on the amount and type of astigmatism.
A small amount may cause almost no noticeable symptoms, while higher levels can significantly affect clarity.
What Causes Astigmatism?
Most astigmatism is simply part of an individual's natural eye shape and optical system.
It can be present from childhood and may run in families.
Astigmatism may remain relatively stable or change gradually over time. It can also change following eye surgery, injury or because of conditions that alter the shape of the cornea.
Is Astigmatism Common?
Yes, very.
Astigmatism is not an unusual or particularly concerning diagnosis in itself. Many spectacle and contact lens prescriptions contain some astigmatism correction.
It can occur alongside:
- Myopia – short-sightedness
- Hyperopia – long-sightedness
- Presbyopia – age-related near-focusing changes
This means someone might, for example, be short-sighted and have astigmatism.
How Is Astigmatism Corrected?
Astigmatism can usually be corrected with:
- Glasses
- Soft toric contact lenses
- Custom contact lenses
- Rigid gas permeable contact lenses
- Scleral contact lenses in selected cases
- Refractive surgery for suitable patients
Modern contact lenses can correct a very wide range of astigmatism.
If you have previously been told that your astigmatism means you “can't wear contacts”, it may be worth asking again. Contact lens technology has changed significantly and specialised or custom designs are available for prescriptions that standard lenses cannot correct.
Learn more about Contact Lenses at Illume →
Can You Have Multifocal Contact Lenses With Astigmatism?
Yes.
People who have both presbyopia and astigmatism have traditionally had fewer contact lens choices, but there are now considerably more multifocal toric contact lens designs available.
Depending on your prescription, options may include daily disposable, reusable and custom-made lenses.
Learn more about Multifocal Contact Lenses →
What Is Irregular Astigmatism?
Most astigmatism is regular, meaning the pattern of corneal curvature is relatively predictable and can be corrected well with glasses or soft contact lenses.
Occasionally, the corneal surface becomes more irregular. This can make vision more difficult to correct with ordinary glasses.
Irregular astigmatism may occur with conditions such as keratoconus, after corneal surgery, following injury or for other reasons.
Specialised corneal imaging called corneal topography can help us assess the shape of the cornea in much greater detail.
Does Astigmatism Mean I Have Keratoconus?
No.
The vast majority of people with astigmatism do not have keratoconus.
However, astigmatism that is unusually high, irregular or changing unexpectedly may prompt your optometrist to investigate the corneal shape more closely.
Illume has advanced corneal topography and also provides specialised assessment and contact lens care for patients with keratoconus and irregular corneas.
Learn more about Keratoconus →
Can Children Have Astigmatism?
Yes. Astigmatism is common in children.
Children may not recognise that their vision is blurry, especially if they have always seen that way.
Significant uncorrected astigmatism during childhood can interfere with the development of clear vision, so children's eye examinations are important where there are symptoms, family history or concerns about vision.
When Should You See an Optometrist?
Book an eye examination if you notice persistent blurry or distorted vision, difficulty with night driving, ghosting around text or lights, eyestrain or headaches.
A change in astigmatism can also be worth investigating rather than simply assuming a stronger prescription is required.
At Illume Eye Care in Ponsonby, Auckland, our optometrists can assess your prescription alongside eye health and, where indicated, detailed corneal imaging.
Frequently Asked Questions About Astigmatism
Is astigmatism an eye disease?
No. Regular astigmatism is a common refractive error rather than an eye disease.
Does astigmatism get worse?
It can change over time. Small gradual changes are common, but rapidly changing or increasingly irregular astigmatism may warrant further assessment.
Can you wear contact lenses if you have astigmatism?
Yes. Toric contact lenses are specifically designed to correct astigmatism, and custom, RGP or scleral lenses can provide further options for more complex prescriptions.
Can astigmatism cause headaches?
Uncorrected astigmatism can contribute to eyestrain, squinting and headaches, although headaches have many possible causes.
Is astigmatism the same as keratoconus?
No. Most astigmatism is regular and unrelated to keratoconus. Keratoconus is a corneal condition that can produce progressive and irregular astigmatism.
Clinically reviewed by an Illume Eye Care Sptometrist | Last reviewed: August 2026
