What is astigmatism?
Astigmatism is the medical term that means the shape of your eye is more curved than it should be. It’s a type of refractive error — an extremely common eye condition that causes blurred vision.
Usually, eyes are round, like a baseball. If you have astigmatism, your eye is shaped like a football or the back of a spoon. This makes light that enters your eyes bend unevenly and affects your vision at all distances.
Visit an eye care specialist as soon as you notice any changes in your eyes or feel like your vision isn’t as clear as it used to be.
What does astigmatism do to your vision?
The parts of your eyes work together like a relay team to pass light that enters your eye along a pathway to your brain. Light passes through your cornea — the clear part at the front of your eye. Your cornea focuses that light through your lens into a signal that hits your retina — the layer at the very back of your eyeball. Your retina converts that light into electrical signals that your optic nerve sends to your brain. Your brain then uses those signals to create the images you see.
If you have astigmatism, light that enters your eye is bent more than it should be. The light can’t properly focus on your retina. This means only parts of an object you’re looking at are in focus. That uneven focus makes objects look blurry or wavy. Astigmatism can affect your vision at any distance — both up close and farther away.
You might experience eye strain — like your eyes are constantly working too hard to see.
What are the types of astigmatism?
Astigmatism is usually caused by your cornea having an irregular shape. Eye care specialists call this corneal astigmatism.
You can also have lenticular astigmatism, where the lens in your eye has an irregular shape. Lenticular astigmatism is often caused by cataracts.
Some people have both corneal and lenticular astigmatism.
Who is affected by astigmatism?
Anyone can experience astigmatism. You can develop it at any point in your life. Some people are born with astigmatism. Others don’t develop it until they’re adults. It can get better or worse over time.
Astigmatism is very common. 1 in 3 people has astigmatism.
FAQs
Symptoms include blurry vision, eyestrain, headaches, and trouble seeing at night. While most people are born with astigmatism, it can also develop from eye injuries, diseases, or surgeries. While you can't prevent it, treatments range from glasses and contacts to surgery like LASIK.
What tests are done to diagnose astigmatism? ›
Three such tests can help detect astigmatism:
- Refraction test: There are two kinds of refraction tests. ...
- Corneal topography: This technology maps a computerized image of the cornea. ...
- Keratometry: A keratometer is another instrument that can measure the curvature of your cornea.
Keratometry: This test is specifically used to check for astigmatism. During this test, your eye doctor will check your cornea using a keratometer, which measures the curvature of the cornea by focusing a circle of light on the cornea and measuring its reflection.
What is astigmatism symptoms and treatment? ›
This causes blurred vision at all distances. Astigmatism is often present at birth and may occur in combination with nearsightedness or farsightedness. Often it's not pronounced enough to require corrective action. When it is, treatment options are corrective lenses or surgery.
How to tell if you have astigmatism? ›
Blurred vision is the most common astigmatism symptom. It also makes it hard to see details on objects, like the words printed on a menu in front of you, or letters on a road sign in the distance. Other astigmatism symptoms include: Seeing a glare or halos around lights.
What can be mistaken for astigmatism? ›
The symptoms of astigmatism and keratoconus are similar, but they are caused by two separate conditions. Put simply: Keratoconus is caused by your cornea misshaping into a cone-like shape. Astigmatism is caused by a curve in your cornea or lens.
Should I wear my glasses all the time for astigmatism? ›
Usually astigmatism above 1 degree causes much visual disturbance. If your vision is affected a lot, you should wear glasses to help your eyes not have to adjust too much. For people with low or low myopia, if eye fatigue and dry eyes do not appear but can still see clearly, they do not need to wear glasses regularly.
How can I test my astigmatism at home? ›
To use an eye chart at home, you'll need to:
- Print the chart.
- Place the chart on a wall with no windows on it.
- Place a chair 10 feet away from the wall. Sit in the chair.
- Make sure the chart is at eye level.
- Cover one eye.
- Read the smallest letters you can see clearly.
- Repeat with the other eye.
The lens, responsible for focusing light onto the retina, gradually loses its flexibility and elasticity with age. This natural aging process can lead to astigmatism worsening over time.
What prescription do you need for astigmatism? ›
They will contain a special cylindrical lens prescription to compensate for the astigmatism. This provides for additional lens power in only specific meridians of the lens. An example of a prescription for astigmatism for one eye would be -1.00 -1.25 X 180.
6 Eye Exercises to Treat Astigmatism
- Eye Massage This exercise restores the shape of the cornea. ...
- Reading It helps to release the strain and pressure caused by astigmatism. ...
- Vision Breaks It relieves eye pressure and strain. ...
- Head Tilting It helps the extraocular muscles to regulate the force they exert on the eyeball.
Astigmatism Treatment. Glasses or contacts can correct almost all cases of astigmatism. But if you have only a slight astigmatism and no other vision problems, you may not need them. If you have a common level of astigmatism, you'll probably have corrective lenses, like glasses or contacts, or surgery.
What is considered a bad astigmatism? ›
75 diopters of astigmatism, and this is considered normal and will likely not require correction. Between . 75 and 2 diopters is considered mild astigmatism. Between 2 and 4 diopters is moderate astigmatism, and 4 or more diopters is considered significant or “bad” astigmatism.
What does vision look like for a person with astigmatism? ›
The most common symptom of astigmatism is blurred or distorted vision at all distances and night glare, making even everyday activities like driving, reading, or playing sports difficult.
Can dry eyes make astigmatism worse? ›
Corneal topography and wavefront sensors have been used to objectively and quantitatively evaluate optical quality, with data showing increases in irregular astigmatism and higher-order aberrations (HOAs) in dry eye patients.
Can astigmatism make you feel sick? ›
Your trusted eye doctor explains that the characteristic manifestation of astigmatism is blurry vision when looking at both close- and far-range objects. You may also experience nausea or vomiting when reading, driving, or doing other daily tasks. Severe eye strain and frequent headaches are common too.
How do they diagnose astigmatism from the prescription? ›
Other terms on your prescription:
If you have a minus sign (-) you are nearsighted; if you have a plus sign (+) or no sign you are farsighted. Cylinder (CYL): Indicates the amount of lens power for astigmatism. If nothing appears in this column you do not have astigmatism.
How do you test for irregular astigmatism? ›
To get the correct diagnosis, the refractive evaluation should be thorough with pinhole testing and retinoscopy. “If you can't achieve your pinhole, then it's time to suspect irregular astigmatism,” she said. And by revealing an unusual red reflex, said Dr. Parker, retinoscopy can also be surprisingly helpful.
How often should you get your eyes checked if you have astigmatism? ›
Adults over 18 with no vision issues can see an eye doctor every other year, but those with vision issues should still see an eye doctor yearly. Those over 50 should see an eye doctor at least yearly. That's because of their risk of developing cataracts or glaucoma increases.
