Astigmatism is a common yet often misunderstood refractive error in the eye. While many people are familiar with terms like nearsightedness (myopia) and farsightedness (hyperopia), astigmatism is less talked about, though it affects millions worldwide. In this blog post, we’ll break down what astigmatism is, its causes, symptoms, and how it can be treated to help you achieve clearer, more comfortable vision.
What Is Astigmatism?
Astigmatism is a condition where the cornea (the clear front surface of the eye) or the lens inside the eye is irregularly shaped. Instead of being perfectly round like a basketball, the cornea or lens in an eye with astigmatism is shaped more like a football. This irregular shape causes light entering the eye to focus on multiple points rather than a single point on the retina, leading to blurred or distorted vision at all distances.
Astigmatism is a refractive error, meaning the shape of your eye prevents light from focusing properly. It can occur alongside other vision problems, such as nearsightedness or farsightedness, but it’s a distinct condition in its own right.
What Causes Astigmatism?
The exact cause of astigmatism is often unknown, but it is generally linked to genetics. Most people are born with astigmatism, although it can also develop later in life due to injury, surgery, or certain eye diseases. The condition can affect one or both eyes and varies in severity.
Here are the main causes of astigmatism:
Genetics: Astigmatism often runs in families, meaning if your parents had it, you’re more likely to have it too.
Corneal Irregularities: The cornea is responsible for most of the eye’s focusing power. When it’s misshapen or uneven, it disrupts how light enters the eye, leading to blurry or distorted vision.
Lens Irregularities: The lens inside your eye can also be irregularly shaped, causing astigmatism. This is known as lenticular astigmatism.
Eye Surgery or Injury: In some cases, a traumatic eye injury or surgery can lead to astigmatism if the cornea or lens is affected.
Symptoms of Astigmatism
People with astigmatism may experience a variety of symptoms, some of which can affect day-to-day activities. These symptoms may vary depending on the severity of the condition. Common signs include:
Blurred or Distorted Vision: This is the most common symptom, where vision at all distances, near and far, appears fuzzy or distorted.
Eye Strain or Discomfort: Individuals with astigmatism may experience eye strain, especially after extended periods of reading, using a computer, or driving.
Frequent Headaches: Due to the eyes working harder to focus, headaches may occur, especially after prolonged visual tasks.
Difficulty Seeing at Night: Astigmatism can cause difficulties with night vision, including glare or halos around lights.
Squinting: People with astigmatism may squint to try to focus better, often leading to eye strain or discomfort.
Diagnosing Astigmatism
To diagnose astigmatism, an eye care professional, usually an optometrist or ophthalmologist, will perform a comprehensive eye exam. This exam includes tests like:
Visual Acuity Test: This basic test checks how clearly you can see at various distances.
Keratometry: This instrument measures the curvature of your cornea, helping determine the severity of astigmatism.
Refraction Test: This test helps determine your exact prescription and measures how light is bent as it enters your eye.
Corneal Topography: In some cases, more advanced tests such as corneal topography may be used to map the surface of your cornea for irregularities.
Treating Astigmatism
While astigmatism can be bothersome, the good news is that it’s treatable. The appropriate treatment depends on the severity of your astigmatism and your overall eye health. Here are the most common treatment options:
Eyeglasses: Prescription eyeglasses are the simplest and most effective treatment for astigmatism. Special cylindrical lenses are used to correct the uneven curvature of the cornea, allowing light to focus correctly on the retina.
Contact Lenses: There are contact lenses specifically designed to treat astigmatism, known as toric lenses. These lenses have different powers in different meridians to correct the uneven curvature of the cornea or lens. Unlike regular spherical lenses, toric lenses are designed to stay in place on the eye, maintaining the correct orientation for proper vision correction.
Refractive Surgery: For those who want a more permanent solution, refractive surgery options like LASIK (Laser-Assisted in Situ Keratomileusis) can reshape the cornea to improve the way light enters the eye and focus it properly on the retina. This procedure can effectively treat mild to moderate astigmatism and is a popular choice for people looking to reduce their dependence on glasses or contact lenses.
Orthokeratology (Ortho-K): This is a non-surgical treatment that involves wearing specially designed contact lenses overnight. These lenses reshape the cornea temporarily, allowing for clear vision during the day without the need for glasses or contact lenses. It’s a popular option for people who don’t want to undergo surgery but are looking for a more permanent solution than regular lenses.
Lens Implants: In some cases, people with severe astigmatism may be candidates for lens implant surgery, where a custom lens is inserted into the eye to correct the shape of the cornea.
Can Astigmatism Get Worse Over Time?
Astigmatism typically remains stable throughout a person’s life, but it can change over time, especially if it’s caused by a disease or injury. Regular eye exams are essential to monitor the condition and ensure that any changes in vision are addressed promptly.
Living with Astigmatism
Astigmatism can feel frustrating, especially if you’re unaware of the condition. But with the right treatment, many people with astigmatism can enjoy clear, comfortable vision. Whether you choose glasses, contact lenses, or surgery, there are plenty of options available to help you manage astigmatism effectively.
If you notice any signs of blurred or distorted vision, or if your vision changes over time, it’s important to schedule an eye exam with an eye care professional. Early diagnosis and treatment can help ensure the best possible outcomes and maintain your eye health for years to come.
Conclusion
Astigmatism is a common eye condition that can significantly affect the quality of your vision if left untreated. Understanding the causes, symptoms, and treatment options for astigmatism is essential for managing the condition and improving your vision. Whether through glasses, contact lenses, or surgery, you have multiple options to restore clearer, more comfortable vision. If you’re experiencing any symptoms of astigmatism, don’t hesitate to visit an eye care professional for a thorough exam and personalized treatment plan.