Astigmatism
Symptoms, causes, treatment, and when to see an optician
Overview
Astigmatism is a very common refractive error caused by an irregularly shaped cornea or lens, which prevents light from focusing evenly on the retina. Instead of being round like a football, the eye is shaped more like a rugby ball, causing vision to be blurred or distorted at all distances. Most people have some degree of astigmatism, and it is easily corrected with glasses, contact lenses, or laser eye surgery.
Symptoms
- Blurred or distorted vision at both distance and near
- Difficulty seeing fine detail, such as small print or distant signs
- Eye strain and discomfort, especially after prolonged reading or screen use
- Headaches, particularly after visual tasks
- Squinting to try to see more clearly
- Difficulty with night driving due to glare and streaked lights
Causes & Risk Factors
- Irregular curvature of the cornea (corneal astigmatism) — the most common cause
- Irregular shape of the internal crystalline lens (lenticular astigmatism)
- Genetics — astigmatism often runs in families and is usually present from birth
- Keratoconus — a progressive thinning and steepening of the cornea
- Previous eye surgery or corneal injury
- Chalazion (meibomian cyst) pressing on the cornea
Treatment Options
Astigmatism is corrected by using lenses that compensate for the uneven curvature of the eye. Glasses with cylindrical or toric lens elements are the simplest and most common correction. Your prescription will include a cylinder value and an axis number, which describe the amount and direction of the astigmatism. Your optometrist will explain these numbers when discussing your results.
Toric contact lenses are specifically designed for astigmatism and are available in daily disposable, monthly, and extended-wear options from all major UK lens manufacturers. Modern toric lenses are very stable on the eye and provide excellent vision for most levels of astigmatism. For people who prefer not to wear glasses or contact lenses, laser eye surgery (LASIK or LASEK) can permanently correct astigmatism in suitable candidates, and is widely available from specialist clinics across the UK.
In most cases, astigmatism remains stable throughout adulthood, though your overall prescription may change with age. Regular eye tests ensure your correction stays up to date. If your astigmatism is increasing progressively, particularly in younger patients, your optometrist may investigate for keratoconus — a condition that requires specialist management.
Prevention Tips
- Astigmatism is largely genetic and cannot be prevented
- Attend regular eye tests so any changes in astigmatism are detected and your prescription is kept up to date
- Avoid rubbing your eyes forcefully, as this may contribute to corneal changes over time
- If you have keratoconus or a family history of it, ensure regular monitoring by your optometrist
When to See an Optician
Book an eye test if you experience blurred vision at any distance, headaches after reading, or difficulty with night driving — astigmatism is easily detected during a routine eye test and simply corrected.
Key Facts
- Category
- Refractive error
- Typically Affects
- All ages (usually present from birth)
- Key Symptoms
- 6 identified symptoms
Detecting Astigmatism
The following eye tests can help detect signs of astigmatism:
- Standard eye test
- OCT retinal scan
- Visual field test
Protect your vision with a regular eye test
Early detection is key. A routine eye test can identify signs of astigmatism before symptoms become noticeable. Book yours today.
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