As a very common eye condition, astigmatism affects millions of people worldwide. It can cause blurred or distorted vision, impacting daily activities and overall quality of life. In this post, we will explore:

• The definition of astigmatism
• Its causes and symptoms
• Diagnosis methods
• Various treatment options, including contact lenses and glasses
• Myths about astigmatism
• Preventive measures
• The importance of professional eye care

Let's explore everything you need to know about managing and understanding astigmatism effectively.

What is Astigmatism?

Astigmatism is a common eye condition where the cornea or lens has an irregular shape, causing vision to be blurry or distorted. This imperfection in the eye's curvature leads to light being refracted improperly, resulting in unclear images.

Importance of Understanding Astigmatism

Knowing about astigmatism is crucial because it affects a significant number of people. Many individuals may not even realize they have it, especially if symptoms are mild. Understanding this condition helps in recognizing its symptoms and seeking appropriate treatment, which can greatly improve one's quality of life. 

Early detection, particularly in children, is important to prevent issues such as poor performance in school and lazy eye.

What is the Main Cause of Astigmatism?

Astigmatism occurs when the cornea or lens of the eye isn't perfectly curved. Instead of having a round shape, these parts of the eye might be more oval or irregular, causing light to bend unevenly as it enters the eye. This uneven refraction results in blurred or distorted vision.

Corneal vs. Lenticular Astigmatism

Astigmatism can be classified into two main types based on where the irregular shape occurs:

• Corneal Astigmatism: This type is more common and happens when the cornea, the clear front part of the eye, is misshapen.
• Lenticular Astigmatism: This occurs when the lens inside the eye has an irregular shape.

Genetic Predisposition

Astigmatism often runs in families, indicating a genetic component. Many people are born with it, and it can become more noticeable as they grow older.

Environmental Factors

Astigmatism can also develop due to various external factors, including:

• Eye Injury: Trauma to the eye can alter the shape of the cornea or lens.
• Eye Disease: Certain conditions, like keratoconus, can cause the cornea to thin and change shape over time.
• Surgery: Procedures on the eye can sometimes lead to changes in its shape, resulting in astigmatism.

Understanding these causes is essential for identifying and managing astigmatism effectively.

How Does Astigmatism Affect Vision?

Astigmatism impacts vision by distorting the way light enters the eye. Normally, the cornea and lens focus light directly onto the retina, creating a clear image. However, with astigmatism, the irregular shape of the cornea or lens causes light to focus on multiple points, either in front of or behind the retina, leading to blurred or distorted vision.

Normal Eye Function vs. Astigmatic Eye Function

In a normal eye, the cornea and lens have a smooth, evenly curved surface that allows light rays to bend (refract) properly. This focused light forms a sharp image on the retina at the back of the eye.

With astigmatism, the cornea or lens is unevenly curved. This irregular shape prevents light from focusing correctly, causing images to be blurred at any distance. Objects both near and far appear out of focus because the light rays are scattered instead of meeting at a single point on the retina.

Impact on Near and Distant Vision

Astigmatism affects both near and distant vision. Unlike myopia (nearsightedness) or hyperopia (farsightedness), which primarily affect one range of vision, astigmatism causes blurriness across all distances. This means that people with astigmatism might struggle to see clearly when reading a book or viewing a distant landscape.

Common Refractive Errors Associated with Astigmatism

Astigmatism often occurs alongside other refractive errors, such as:

• Myopia (Nearsightedness): People with myopia see nearby objects clearly, but distant objects appear blurry.
• Hyperopia (Farsightedness): Those with hyperopia can see distant objects well, but struggle with seeing things up close.

These combined vision problems can further complicate one's visual experience, making it important to address all aspects during diagnosis and treatment.

What Are the Symptoms of Astigmatism?

Astigmatism can present various symptoms, which can vary in severity depending on the individual and the extent of the condition.

• Blurry or Distorted Vision: One of the most common signs of astigmatism is experiencing blurry or distorted vision at all distances. This occurs because the irregular shape of the cornea or lens prevents light from focusing correctly on the retina.
• Eyestrain and Headaches: Due to the constant effort needed to focus on objects, people with astigmatism often experience eyestrain and frequent headaches.
• Squinting and Eye Discomfort: To try to see more clearly, individuals with astigmatism may squint or strain their eyes, leading to discomfort and fatigue.

Importance of Eye Exams for Diagnosis

These symptoms are not unique to astigmatism and can be related to other vision problems. Therefore, it's crucial to have regular eye exams for a proper diagnosis. An eye care professional can conduct various tests to determine if astigmatism is the cause of these symptoms and recommend appropriate treatment options.

How is Astigmatism Diagnosed?

Diagnosing astigmatism involves several tests that help eye care professionals assess the shape of the cornea and the way light refracts in the eye.

• Eye Chart Test: This is a basic test where you are asked to read letters on an eye chart at various distances. It measures visual acuity and helps determine how clearly you can see.
• Phoropter and Autorefractor: During a phoropter test, you look through a binocular-like device and indicate which letters you see more clearly. This helps the doctor determine your prescription for glasses or contact lenses. An autorefractor, on the other hand, shines a light into the eye and measures how it changes as it bounces off the back of the eye, providing an automatic measurement of refractive error.
• Keratometer and Corneal Topography: A keratometer measures the curvature of the cornea by focusing a circle of light on it and measuring its reflection. Corneal topography provides a detailed map of the cornea's surface, highlighting any irregularities in its shape.

These tests together help in accurately diagnosing astigmatism and determining the best course of treatment to correct the vision.

What Are the Treatment Options for Astigmatism?

There are several effective ways to correct astigmatism, depending on the severity and individual preferences.

• Eyeglasses and Contact Lenses: The most common treatments are eyeglasses and contact lenses, which help refocus light onto the retina. Eyeglasses are made with special cylindrical lenses that compensate for the irregular shape of the cornea or lens.
• Types of Contact Lenses:
• Toric Contact Lenses: These lenses are designed specifically for astigmatism. They have different powers in different meridians of the lens to correct the uneven curvature of the cornea.
• Rigid Gas Permeable (RGP) Lenses: These lenses are more rigid and can provide clearer vision for some people with severe astigmatism because they maintain their shape while on the eye, compensating for the cornea's irregularities.
• Refractive Surgery Options (LASIK): For a more permanent solution, refractive surgery such as LASIK can be considered. During LASIK, a laser reshapes the cornea to correct the way light is focused on the retina. This procedure can significantly reduce or eliminate the need for glasses or contact lenses.

The choice of treatment depends on individual needs, lifestyle, and the extent of astigmatism. An eye care professional can help determine the most suitable option.

If you want to learn more about Toric Contact Lenses, you can visit our Toric & Astigmatism collection and compare the benefits of each one.

What You Should Know About Contacts Lenses for Astigmatism

Contact lenses can be a great option for correcting astigmatism, but there are some important factors to consider.

Benefits of Toric Lenses

Toric lenses are specifically designed to correct astigmatism. Unlike regular contact lenses, toric lenses have different powers in different meridians of the lens, allowing them to correct the uneven curvature of the cornea. They provide clear and stable vision by maintaining their position on the eye.

Importance of Proper Fit and Orientation

For toric lenses to work effectively, they must fit properly and maintain the correct orientation on the eye. Toric lenses have a specific axis that needs to align correctly with the astigmatism to ensure clear vision. A proper fit is crucial because if the lenses rotate or shift out of position, vision can become blurry.

Specialty Contact Lenses

In addition to toric lenses, there are other specialty contact lenses available for those with astigmatism:

• Hybrid Lenses: These lenses combine the comfort of soft contact lenses with the clear vision provided by rigid lenses. They have a hard center and a soft outer ring, offering both stability and comfort.
• Scleral Contacts: These larger lenses cover the entire cornea and rest on the sclera (the white part of the eye). Scleral lenses are especially beneficial for individuals with severe astigmatism or irregular corneas, as they provide a stable and comfortable fit.

Choosing the right type of contact lenses for astigmatism involves consulting with an eye care professional who can recommend the best option based on your specific needs and lifestyle.

If you are new to contact lenses and want to learn the practical tips, here is our detailed contact lenses guide for beginners!

Common Myths About Astigmatism

Astigmatism is often misunderstood, leading to several myths and misconceptions about the condition and its causes.

Debunking Myths

• Myth: Reading in Low Light Causes Astigmatism: One of the most common myths is that reading in low light can cause or worsen astigmatism. This is not true. While reading in poor lighting can cause eye strain and discomfort, it does not affect the shape of the cornea or lens.
• Myth: Sitting Too Close to the TV Causes Astigmatism: Another widespread misconception is that sitting too close to the television can cause astigmatism. There is no evidence to support this claim. Sitting close to the TV may cause temporary eye strain but does not lead to astigmatism.
• Myth: Astigmatism Will Always Get Worse: Some people believe that astigmatism will inevitably worsen over time. While it can change, especially in children, it doesn't always get worse. Regular eye exams can help monitor any changes in vision and ensure appropriate treatment.
• Myth: Only Surgery Can Fix Astigmatism: Many think that surgery is the only way to correct astigmatism. However, most cases can be effectively managed with eyeglasses or contact lenses. Surgery, like LASIK, is an option for those seeking a more permanent solution but is not the only treatment available.

Understanding the facts about astigmatism can help in managing the condition effectively and avoiding unnecessary fears or misconceptions.

Who is at Risk for Astigmatism and How Can It Be Prevented?

Astigmatism can affect anyone, but certain factors can increase the risk of developing this condition.

Hereditary Risk Factors

Astigmatism often runs in families, meaning it can be inherited. If parents have astigmatism, there is a higher chance their children will also have it. This genetic predisposition is one of the primary risk factors.

Preventive Measures to Protect Eyes from Injury

While you cannot prevent genetically inherited astigmatism, you can take steps to protect your eyes from injury, which can lead to or worsen astigmatism:

• Use Protective Eyewear: Always wear safety glasses or goggles when engaging in activities that could cause eye injury, such as working with power tools, playing certain sports, or handling chemicals.
• Avoid Eye Strain: Although eye strain doesn't cause astigmatism, it can make it more uncomfortable. Take regular breaks when doing tasks that require intense focus, like reading or using a computer.
• Regular Eye Exams: Routine eye check-ups can help detect astigmatism early and monitor any changes. Early detection allows for timely intervention, which can prevent complications.

By understanding the risk factors and taking preventive measures, you can help maintain good eye health and manage astigmatism effectively.

Conclusion

Astigmatism is a common vision condition caused by an irregularly shaped cornea or lens, leading to blurred or distorted vision. It can be classified as corneal or lenticular astigmatism and is often inherited. Symptoms include blurry vision, eyestrain, headaches, and squinting. 

Diagnosis involves various tests such as the eye chart test, phoropter, autorefractor, keratometer, and corneal topography. Treatment options include eyeglasses, contact lenses (such as toric and RGP lenses), and refractive surgery like LASIK.

Importance of Early Detection and Proper Treatment

Early detection of astigmatism is crucial, especially in children, to prevent complications and ensure effective management. Regular eye exams can help identify astigmatism early, allowing for appropriate treatment to improve vision and quality of life.

Encouragement to Seek Professional Eye Care

If you experience any symptoms of astigmatism or have concerns about your vision, it is important to seek professional eye care. An eye care professional can provide a comprehensive examination, accurate diagnosis, and recommend the best treatment options tailored to your needs. Prioritizing eye health and regular check-ups can help maintain clear and comfortable vision.