Astigmatism is a type of condition which affects the eyes known as a refractive error. It occurs when the cornea or lens is irregularly curved, affecting how light is refracted in the eye, leading to several different issues such as blurry vision, squinting, headaches, straining of the eyes, and more.
Astigmatism is a common condition that often co-occurs with another refractive error, either nearsightedness or farsightedness. Fortunately, you can correct these issues with the use of glasses, contacts, or through surgery.
What Causes Astigmatism?
The cause of astigmatism is an irregularity in the curvature of either the cornea or the lens. This irregularity can result from an injury to the eye, a surgery, certain medical conditions, or eye disease, but many times it is simply the way the patient was born. It is still unclear why the curvature of the cornea or lens might vary from person to person, but it is a heritable trait.
Symptoms of Astigmatism
Some of the most common symptoms of astigmatism include the following:
- Frequent squinting
- Difficulty seeing at night
- Eye discomfort
- Blurry or distorted vision
As you can see, these symptoms are relatively vague, so if you’re experiencing any of them, then astigmatism could very well not be the cause. However, it’s essential to make sure you see a doctor who can help you form a diagnosis. Disregarding issues with your vision can potentially be a danger to yourself and others.
If you’re experiencing any of the symptoms associated with astigmatism, it’s best to see your eye doctor form a diagnosis. They will first give you a vision test to determine how you can see from various distances. If the vision test suggests that you may have astigmatism, the eye doctor will then employ a few different tools to measure the curvature of your cornea and determine what kind of corrective lenses you’re going to need.
Your doctor will use the following devices in your diagnosis.
This tool can be used to measure the curvature of your cornea to determine if there is an irregularity. In some instances, your doctor may measure your corneal topography to get an even more detailed assessment of your cornea’s surface.
This tool essentially allows you to test several different lens shapes to determine which one can correct your astigmatism most effectively. You will look through the device as it cycles through several different lenses and answer questions from your eye doctor regarding which ones provide the clearest vision.
The autorefractor is another tool doctors can use to determine which corrective lenses would be best suited for you. Instead of cycling through different lenses like the phoropter, this tool shines light into your eye and observes how it changes when reflected off its back.
Treatments for Astigmatism
It’s not always necessary to treat astigmatism if the case is mild enough. However, in the event that treatment is necessary, it can almost always be corrected through prescription glasses, contact lenses, or a surgical procedure. For more information on these treatments, read on.
Glasses and Contacts
When you receive your astigmatism diagnosis from your eye doctor, they will determine which corrective lenses would be best suited for you. You may receive prescription glasses or soft contacts that can help counteract the effects of astigmatism. If your condition is more severe, you may receive GPR (gas-permeable rigid) lenses. These lenses actually reshape your cornea so that light refracts properly off of them.
You may have heard of LASIK surgery before. It’s a procedure that can permanently reshape your irregularly curved cornea. There are a few other types of refractive surgeries that serve the same purpose, as well.
Here are some frequently asked questions regarding astigmatism.
What Does Vision Look Like with Astigmatism?
While certain mild cases actually won’t affect vision at all, in most instances, astigmatism causes vision to be blurry and distorted.
Can Straining Your Eyes Cause Astigmatism?
Some believe that one can develop or exacerbate the symptoms of astigmatism by doing things that strain the eyes, such as reading in poor lighting or sitting too close to an illuminated screen. That is a myth, and although you can develop astigmatism later in life, this is not one of the potential causes.
Does Astigmatism Grow Worse Over Time?
Yes, uncorrected astigmatism will most likely result in a worsening of your vision over time. Although it may occur relatively slowly, there will come the point when your vision is so poor that correction is a necessity.