Here’s Your Ultimate Guide to Astigmatism

As common as nearsightedness and farsightedness, astigmatism is a condition in the eye that causes blurred vision. It occurs when your eyes’ cornea or lens prevents light from focusing on the retina. Astigmatism is also commonly referred to as refractive errors mainly because of the eyes’ incapability to properly focus light.

Defining Astigmatism

Astigmatism can vary in different degrees. Some may not require treatment because this condition only make involves a little discomfort that it can usually go unnoticed. In contrast, it can also be severe, and a trip to your optometrist becomes necessary.

Just like other eye conditions, having astigmatism is not an easy thing. While it may decrease over time, the possibility of it getting worse still remains. If you are diagnosed with astigmatism, here is a run through of everything you must know about your condition.

What causes astigmatism?

To start with, it is necessary to get to the root of the problem. This is so we can gain a better understanding about this condition.

Astigmatism is a refractive error. As previously stated, an irregularly shaped cornea causes the light to bend as it passes through your eyes. The shape of your cornea greatly affects the way your eyes absorb light. A normal cornea has a symmetrical curvature.

And a cornea that does not focus light evenly has a shape that is similar to a football. Its meridians are bent differently, making it appear like an oblong instead of a perfectly rounded shape.

Your cornea has two meridians. If you associate it with a clock, the line that connects 12 and 6 is the first meridian, and the line that connects 3 and 9 is the second meridian. Basically, your principal meridians are perpendicular to each other.

As the light passes through your cornea, the retina captures the unevenly distributed light. The retina then converts the light into messages and travel to your brain through the connecting optic nerves.

Your brain interprets the picture as something that seems blurry and stretched out.

Astigmatism can be hereditary or something that develops over time. It can also affect both children and adults.

Types of astigmatism:

There are three primary types of astigmatism:

• Myopic Astigmatism

This type of astigmatism indicates that your principal meridians are both nearsighted (myopia). Myopia is a condition in which distant objects appear out of focus.

• Hyperopic Astigmatism

This type of astigmatism means that your meridians are farsighted (hyperopia). Hyperopia is also a refractive error. However, in contrast to myopia, distant object becomes focused behind the retina. Thus, the closer the object is to the viewer’s eyes, the more blurry it appears.

• Mixed Astigmatism

This type of astigmatism indicates that one of your principal meridian is nearsighted, while the other is farsighted. This means that light enters in two focal points, in front and behind your retina.

That is to say, It is important to identify which type of astigmatism you have so that you can also get the proper treatment.

How can you diagnose astigmatism?

If you suspect that you have astigmatism, consult this immediately with your eye doctor. Particularly, only optometrists can correctly detect this condition through a routine eye exam.

An eye exam to specifically detect astigmatism uses the same instruments and techniques to also detect other refraction errors such as myopia and hyperopia. To determine this condition, your eye doctor projects a beam of light into your eye.

This procedure allows your doctor to examine the movement of reflected lights inside your eyes. Your doctor then introduces lenses to identify the refractive error of the patient. This procedure is called retinoscopy.

However, some eye doctors perform other automated eye care practices to hasten the test to determine astigmatism. Autorefraction uses a machine called autorefractor to provide an objective data about your eyes’ refractive errors.

To get a more accurate data, patients need to stay still and focus on an object for several seconds.

Whether or not your eye doctor opts to perform autorefraction, it is still necessary to do a second test called manual refraction using a phoropter. The doctor places the phoropter with lenses in front of your eyes to identify which lens is best for you.

Click here to read an article about eye exams and its importance.

What are the symptoms of astigmatism?

The signs and symptoms of astigmatism may differ among individuals, but here are the most common ones:

• Blurry and distorted vision (near or far objects)
• Eyestrains
• Headaches
• Squinting
• Eye irritation
• Difficulty seeing at night

If you experience these symptoms, pay your eye doctor a visit to get your eyes checked.

How to correct astigmatism?

There are several ways to correct astigmatism. Your eye doctor may prescribe you to wear eyeglasses, contact lenses, or undergo a laser surgery.

If your astigmatism is mild enough to not cause any sort of discomfort, your doctor may suggest no treatment.

In most cases, wearing prescription glasses is what most doctors recommend.

Additionally, individual lifestyle can also affect how you treat this condition.

If you mostly work in front of the computer, doctors may require you essential steps to rest your eyes.

These steps can help to avoid eye strains. If you are more of a physically active person, contact lenses may be a better option for you.

Here are ways to correct astigmatism:

Corrective lenses

Eyeglasses are the usual approach to correct astigmatism. An optometrist performs a comprehensive eye exam to determine your refractive errors and identify your correct prescription.

It is recommended that you visit your eye doctor at least once a year to avoid worsening of any eye conditions.

Toric Lenses for Astigmatism

Toric lenses are geometrically shaped lenses that works to correct the specific formation of the cornea that leads to astigmatism.

Lenses to correct astigmatism must have a cylinder lens power and a corresponding axis designation. To understand more about these corrective lenses, check this article.

Contact Lenses function as the first refractive surface for light rays that enter the eye. This causes a more precise refraction or focus for any near or far objects.

In many cases, contact lenses provides a generally comfortable feeling compared to eyeglasses. This option is usually safe and effective only if you know how to properly apply and care for the lenses.

If you decide to opt for contact lenses to correct astigmatism, discuss this with your eye care doctor first.

To know more about the pros and cons of both corrective lenses, see Eyeglasses or Contact Lenses: Which is Better for You?

Surgery

Refractive Surgery can change the shape of the cornea permanently and correct refractive errors. This procedure restores the ability of your eyes to focus through allowing the light to focus precisely in the retina.

There are many types of refractive surgeries. An optometrist can help you decide if surgery is an option for you. However, surgery are not right for everyone.

Laser eye surgery may not be suitable if:

• If you are under 18 years old.
• If your vision is still changing. It is necessary to have a stable vision for at least one year before laser surgery.
• You have diabetes.
• If you are pregnant or breastfeeding.
• If you have an immune condition that makes it harder to recover after surgery.
• If you have other existing eye conditions.
• If you are taking certain medications.

Furthermore, there are also risks that are related to laser surgeries. Your surgeon may worsen the condition if he or she removes a tissue by mistake.

You may also experience dry eyes, which is common for patients that underwent an eye surgery. Ensure that your surgeon is qualified and experienced before performing certain procedures.

References:

“Facts About Astigmatism” https://nei.nih.gov/health/errors/astigmatism

“Astigmatism Hyperopia and Myopia Symptoms & Causes” http://www.childrenshospital.org/conditions-and-treatments/conditions/a/astigmatism-hyperopia-and-myopia/symptoms-and-causes

“Astigmatism” https://www.healthline.com/health/astigmatism