What It Really Means When You Have Astigmatism
Astigmatism is a common vision problem. If you have astigmatism, it means your eye is an irregular shape, often described as football- or cone-shaped. The irregular curve of your cornea makes light pass through or refract differently. The light hits your cornea and goes through to your retina. Someone who doesn't have astigmatism has a smooth curve in their corneas, making it easy for light to refract correctly to the retina. Their eyes have a more spherical shape, like a basketball. When you have astigmatism, that light doesn't refract the same because the cornea's surface doesn't have a smooth curvature.
There are two different types of astigmatism — lenticular astigmatism and corneal astigmatism. Each type affects a different part of your eye; lenticular astigmatism affects the lens of your eye, while corneal astigmatism affects the cornea of your eye. You can have astigmatism along with nearsightedness or farsightedness, or both. Your cornea is the outer part of your eye, and your lens is just behind your cornea. So, what causes your cornea or lens to be this shape? (via the American Academy of Ophthalmology (AAO), Medical News Today, and WebMD).
Causes and symptoms of astigmatism
Doctors don't know why some people get astigmatism. There are some theories, such as genetics. It could run in families and is sometimes present at birth. Young children won't know they have it and will need a complete eye exam to get diagnosed. You should bring your child to see the eye doctor at six months old, three years old, before first grade, and every one to two years after that, depending on their risk factors.
While it's likely inherited, there are other possible causes such as an eye injury, surgery, or eye disease. Astigmatism could get better or worse over time, making it important to see your eye doctor regularly. There is a rare eye condition called keratoconus that causes astigmatism, but keratoconus also causes the cornea to become thinner.
Symptoms of astigmatism are blurred or distorted vision, eye strain, squinting to see clearer, trouble seeing at night, headaches, and poor depth perception. If you have any of these symptoms, see your eye doctor for a proper diagnosis and treatment (via the American Academy of Ophthalmology (AAO), Medical News Today, WebMD, and Lasik MD Vision).
Treatments for astigmatism
Treatments for astigmatism are prescription glasses, contact lenses, orthokeratology (Ortho-K), or laser surgery. Mild cases of astigmatism are simply treated with prescription glasses or contacts. Moderate to severe astigmatism could require surgery.
The contact lenses for astigmatism are called toric lenses, and are shaped differently to compensate for the irregular eye shape and help you see clearer. Toric contacts work for both types of astigmatism — corneal astigmatism and lenticular astigmatism. If you get both glasses and contact lenses for your astigmatism, you may notice that you can see better with the contacts. They tend to do a better job at correcting the eye shape.
Ortho-K is a temporary treatment where your doctor will give you rigid contacts — also known as retainer lenses — to wear for limited times, usually only while you sleep. The rigidness of the contact helps to reshape the eye so you can see clearly temporarily. If you stop using them, your astigmatism will likely return.
If you have moderate to severe astigmatism, your eye doctor may recommend surgery. Laser eye surgery — also called Lasik — will correct the shape of the lens or the cornea, so you don't have astigmatism anymore. You can weigh the benefits and risks with your eye doctor to determine which treatments are best for you (via the American Academy of Ophthalmology (AAO), Medical News Today, WebMD, Lasik MD Vision, and CooperVision).