Astigmatism is a common eye condition that happens when the cornea, or lens of the eye, is oval-shaped instead of round. This change in shape stops light from focusing correctly on the retina (the back of the eye), leading to blurry or distorted vision. Astigmatism can change or worsen over time, making everyday activities such as reading, driving, or looking at screens more challenging.
There are several reasons why astigmatism can worsen over time. Some changes happen naturally with age, while others result from injury, underlying conditions, or lifestyle factors.
1. Aging
Age-related changes to the eye are among the most common reasons why astigmatism gets worse. As you age, the shape of the cornea can gradually change. The muscles that help your eyes focus may also weaken, making blurry vision from astigmatism more noticeable. Aging can also cause the eyelids to lose firmness and slightly change their position, which may change the pressure they have on the cornea and affect its shape over time.
2. Eye Injuries
Eye injuries can cause or worsen astigmatism. Corneal scratches, surgical scars, or other trauma can change the shape of the cornea or lens, affecting how light enters the eye and leading to blurred vision or increased astigmatism.
3. Eye Conditions
Certain eye conditions can worsen astigmatism, including:
- Keratoconus: This progressive condition (conditions that worsen over time) is where the cornea thins and bulges outward into a cone shape. This changes how light enters the eye and often leads to irregular astigmatism. It typically starts in the teenage years or early adulthood and may gradually worsen over time.
- Pterygium: This causes tissue to grow on the white part of the eye that can extend onto the cornea, changing the cornea’s shape and increasing astigmatism.
- Cataracts: This is a clouding of the eye’s lens that usually develops with age. Cataracts can worsen astigmatism if the lens becomes misshapen or if the clouding changes the way the eye bends light, making existing astigmatism more noticeable.
- Fuchs’ endothelial dystrophy: This damages cells in the cornea, causing fluid build-up that can lead to swelling and shape changes that may worsen astigmatism.
4. Screen Use
Spending extended periods of time looking at smartphones and computers may worsen astigmatism. Looking downward at a screen can increase eyelid pressure on the cornea, temporarily changing its shape. Reduced blinking and spending a long time focusing on a screen from a short distance may also affect the cornea’s shape over time.
Many people with astigmatism are born with it. Congenital astigmatism occurs when a baby is born with an irregularly shaped cornea or lens. This type of astigmatism often remains stable throughout childhood and may gradually worsen with age, especially by your mid-40s.
Even if you aren’t born with astigmatism, genetics (traits passed down in families) can put you at a higher risk of developing it.
In some cases, astigmatism develops later in life. This can occur after an eye injury, eye surgery, or due to underlying eye conditions or age-related changes that gradually alter the shape of the cornea.
You can’t prevent astigmatism from developing. However, there are several ways to help prevent it from worsening, such as:
- Stay aware: Pay attention to any changes in your vision. Blurry vision, frequent headaches, and eye strain may be signs that your astigmatism is changing.
- Get regular eye exams: Routine eye exams help detect small changes in your eye health and vision. Adults should have a comprehensive eye exam every one to two years.
- Wear eye protection: Protective eyewear can help prevent injuries that could change the shape of your cornea and worsen astigmatism. Wear safety glasses or goggles when participating in sports, doing yard work, or working with tools or chemicals. Choose wraparound sunglasses that block 100% of the sun’s ultraviolet (UV) rays.
- Manage underlying conditions: Keep up with treatments for any health conditions that may affect your eyes, like diabetes or high blood pressure.
- Take screen breaks: Extended screen time can strain your eyes, especially if you spend a lot of time looking down at your phone or tablet. Follow the 20-20-20 rule: every 20 minutes, look at something 20 feet away for 20 seconds.
- Eat a balanced diet: This includes plenty of fruits and vegetables, rich in vitamins A, C, and E, which can support eye health.
- Avoid rubbing your eyes: Rubbing your eyes frequently or with excessive pressure can damage the cornea or alter its shape.
There are several effective treatment options for astigmatism, including:
- Eyeglasses: Standard eyeglasses with cylindrical (curved) lenses help focus light correctly on the retina, improving blurry or distorted vision that can happen with astigmatism.
- Toric contact lenses: Unlike standard soft contact lenses, toric lenses are specially designed to correct astigmatism by compensating for the uneven curvature of the cornea. They stay in a stable position on the eye, which helps light focus properly on the retina and improves overall vision.
- Rigid gas permeable contact lenses (RGP lenses): These are firm lenses that sit on the cornea and create a smooth surface over its irregular shape, helping light enter more evenly and improving sharpness and contrast. RGP lenses are beneficial for people with moderate to severe or irregular astigmatism who need more precise vision correction.
- Laser eye surgery: Laser procedures, such as laser-assisted in situ keratomileusis (LASIK), can correct astigmatism by reshaping the cornea so that light focuses more accurately on the retina. Laser surgery offers a long-term or permanent solution for astigmatism.
Astigmatism can worsen over time due to aging, eye injuries, or conditions like keratoconus. While you can’t always prevent changes in astigmatism, there are steps you can take to help protect your vision.
Regular eye exams, protective eyewear, a healthy diet, and screen breaks all support long-term eye health. Treatments like eyeglasses, contact lenses, or laser surgery can greatly improve how clearly you see and how comfortably you go about your day.
