Many daily activities rely on our ability to see clearly. But common refractive errors like astigmatism and myopia can blur your vision, making these everyday tasks more difficult. Astigmatism and myopia affect how your eyes bend light.
Myopia, or nearsightedness, makes distant objects blurry due to an elongated eye shape which forces light to focus ahead of the retina. Astigmatism, caused by an irregular cornea shape, refracts light unevenly, blurring or distorting vision at all distances. It can coexist with myopia or hyperopia (farsightedness).
Understanding the difference between these 2 conditions can help your eye doctor manage them effectively.
What Is Astigmatism?
Astigmatism is a common vision condition that causes blurred or distorted sight at all distances. It occurs due to an irregular shape of the cornea, the clear front cover of the eye. Instead of being round, the cornea can have an oblong shape—similar to a rugby ball. As light enters the eye, it’s refracted more in one direction than the other, allowing only part of the object to be in focus at a time. Objects at any distance can appear blurry and wavy.
Astigmatism is believed to be largely hereditary. Other possible causes can include pressure from the eyelids on the cornea, incorrect posture, or an increased use of the eyes for close work.
Symptoms of astigmatism often include eye strain, headaches, squinting to see clearly, and difficulty driving at night. These symptoms may be subtle, and many people live unknowingly with mild astigmatism. It often occurs with other vision disorders like myopia (nearsightedness) and hyperopia (farsightedness), which may confuse its identification.
It’s estimated that about 40% of adults in the US have astigmatism. Globally, it affects 1 in 3 individuals, making it a common vision condition.
What Is Myopia?
Myopia, also known as nearsightedness, is a common vision condition where close objects appear clear, but distant objects appear blurry. This happens when the eyeball grows too long from front to back, causing light entering the eye to focus not on the retina but in front of it.
Myopia is generally associated with a combination of genetic and environmental factors. Increased reading and screen time, along with less time spent outdoors, have been linked to the rise of myopia in recent years.
Symptoms of myopia often include squinting, eye strain, and headaches, making it difficult for individuals to perform tasks that require distance vision, such as driving, watching a movie, or reading on a whiteboard. Myopia can lead to serious eye conditions like retinal detachment or glaucoma in severe cases.
Myopia is becoming a global public health issue, according to the Myopia Institute. It is projected to affect nearly 5 billion people by 2050.
Key Differences Between Astigmatism & Myopia
While both astigmatism and myopia affect vision, they have different causes, symptoms, and impacts on vision. Here are the key differences.
Underlying Causes
Astigmatism: This condition is typically caused by an irregularly shaped cornea, which prevents light from focusing correctly on the retina.
Myopia: In most cases, myopia results from the eyeball being too long, causing light to focus before it reaches the retina.
Symptoms & Challenges
Astigmatism: Individuals may experience blurred or distorted vision at all distances, difficulty seeing at night, and eye strain or discomfort.
Myopia: Symptoms include blurred distance vision, squinting, eye strain, and headaches. Tasks like driving or watching a film can be challenging.
Impact on Near & Distant Vision
Astigmatism: This condition affects both near and distant vision due to the irregular shape of the cornea or lens.
Myopia: Near objects are clear, but distant objects appear blurry due to the elongated shape of the eyeball.
Diagnosis & Treatment Options
Your eye doctor can diagnose astigmatism and myopia through a comprehensive eye exam which includes a series of tests to evaluate the patient’s vision and eye health. These tests may involve using an eye chart, a retinoscope, or a phoropter.
Astigmatism is typically corrected with eyeglasses or contact lenses, which compensate for the uneven curvature of the cornea or lens. In some cases, refractive surgery may be considered to reshape the cornea.
Myopia, on the other hand, is commonly treated with eyeglasses or contact lenses that correct for the elongated shape of the eyeball. Refractive surgery may also be an option for some candidates.
Early Detection Is Key
Regular eye exams are essential for the early detection and management of both conditions. In addition, they allow for ongoing monitoring of eye health and the effectiveness of any prescribed treatment.
At Signature Eye Care, we stress the importance of seeking professional help for accurate diagnosis and personalized treatment. Don’t put your vision at risk. Book your eye exam with us today, or explore our range of vision correction options on our website.
With care and treatment, clear and comfortable vision isn’t just a possibility— it can be a reality.