Refractive Errors: Nearsightedness, Farsightedness & Astigmatism
Seeing Clearly Starts Here: Understanding Refractive Errors
If you've ever squinted at a highway sign, held a menu at arm's length, or struggled to follow a presentation on a screen, you've experienced what millions of people deal with every day — a refractive error. Refractive errors are the most common vision conditions in the world, affecting people of all ages, backgrounds, and lifestyles. The good news is that they are also among the most treatable. At Columbia Eye Associates, we help patients understand their prescriptions, find the right correction, and maintain optimal eye health for years to come.
What Is a Refractive Error?
The eye works like a camera. Light enters through the cornea and lens, which bend (or "refract") it so it lands precisely on the retina at the back of the eye. When the shape of the eye is slightly off — too long, too short, or irregularly curved — light doesn't focus where it should, and the result is blurred vision. This mismatch is called a refractive error, and it comes in three primary forms.
Nearsightedness (Myopia)
Nearsightedness, or myopia, occurs when the eye is slightly too long or the cornea is too curved, causing light to focus in front of the retina rather than on it. The result: objects up close appear clear, while distant objects look blurry. Myopia is increasingly common, particularly in children and young adults, and tends to progress through the teenage years before stabilizing in adulthood. Myopia management strategies — including special contact lenses, atropine eye drops, and orthokeratology — can help slow its progression in younger patients.
Farsightedness (Hyperopia)
Farsightedness, or hyperopia, occurs when the eye is too short or the cornea is too flat, causing light to focus behind the retina. Mild hyperopia is common in young children and often corrects itself as the eye grows. More significant farsightedness causes difficulty with near tasks like reading, and can also contribute to eye strain and headaches — especially after prolonged close work. In some children, untreated hyperopia can lead to accommodative esotropia, a type of crossed eye caused by excessive focusing effort.
Astigmatism
Astigmatism occurs when the cornea or lens has an irregular shape — more like a football than a sphere. Instead of focusing light to a single point on the retina, the eye focuses it at multiple points, producing blurred or distorted vision at all distances. Astigmatism often occurs alongside nearsightedness or farsightedness, and it's very common. Many patients don't realize they have it until a comprehensive exam reveals the irregular shape of their cornea.
Correction Options
All three refractive errors can be effectively corrected with prescription eyeglasses or contact lenses tailored to your exact measurements. For eligible patients, refractive surgery offers a longer-term solution by reshaping the cornea to improve how light is focused.
The most important step is getting an accurate, up-to-date prescription from a comprehensive eye exam — not an online test or a quick vision screening.
At Columbia Eye Associates, we take the time to get your prescription right, so you can see your world clearly and comfortably.
Schedule your comprehensive eye exam today.