What is astigmatism?

Astigmatism is a common eye problem that causes blurred vision, headaches, and eye strain.

If you have an astigmatism, the clear outer covering of your eye (cornea, or lens) is more oval-shaped than round. Your cornea directs light rays into your eye. Then it focuses the light rays on the retina at the back of the eye. If the surface of the cornea has an oval shape, light rays may not focus on the retina as they should.

Eyeglasses, contact lenses, or surgery can correct this problem. Contact lenses for astigmatism are called toric lenses. Some may need to be custom-made. They may cost more than ordinary contact lenses.

Reduce eyestrain

• Use good light for reading, work, or study. Use a soft background light plus a light on your task.
• Choose large-print books. Adjust the print size on your computer and online when possible.
• Take frequent breaks when you do close work that can be hard on your eyes. Blink often. Every 20 minutes, look at something 20 feet away for 20 seconds (the "20-20-20" rule). Close and rest your eyes when they feel tired or dry.
• Avoid glare on TV and computer screens. Place your TV or computer screen where lights do not reflect on the screen. Some people find it easier to work on a computer in a dimly lit room. Special nonglare screens that fit over the computer screen also may help.

Keep your eyes healthy

• Have eye exams as often as your doctor recommends.
• Wear sunglasses to block harmful sunlight. Buy sunglasses that screen out ultraviolet A and B (UVA and UVB) rays.