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Refractive Errors


Refractive errors refer to a disorder in which the eye is irregularly shaped, causing light to focus on the wrong area of the retina. Refractive errors result in varying degrees of blurry vision, but can be treated with eyeglasses, contact lenses, and refractive surgery.

Causes of Refractive Errors

Many experts believe that refractive errors are caused by genetic and environmental factors. Ocular injury can also lead to the development of refractive errors.

Diagnosing Refractive Errors

If you have trouble with near or distance vision, it is important to schedule an appointment with an experienced ophthalmologist. An ophthalmologist can perform the necessary eye tests to accurately diagnose your vision condition.

Lower-Order Aberrations

Millions of people in the United States have some sort of vision imperfection that results in less than perfect vision. Many patients suffer from lower-order aberrations that cause blurry vision when focusing on near or far objects. Lower-order aberrations include nearsightedness (myopia), farsightedness (hyperopia), and astigmatism. An abnormally shaped cornea causes these vision imperfections. When the cornea is ideally shaped, light properly reflects off of the cornea and produces clear, crisp vision.

Myopia (Nearsightedness)

Myopia, or nearsightedness, occurs due to an irregularly shaped cornea. This causes light rays to focus in front of the retina, rather than directly on the retina. Nearsighted patients experience clear vision up close, but distant objects will be fuzzy. Learn more about myopia, as well as the treatments available for nearsighted individuals.

Hyperopia (Farsightedness)

Hyperopia, or farsightedness, occurs due to an irregularly shaped cornea that causes light to focus behind the retina, rather than directly on the retina. Farsighted individuals have difficulty seeing objects up close, but see distant objects clearly. Learn more about hyperopia and the treatment options available for farsighted patients.


The most common of all eye disorders, astigmatism occurs when the eye is shaped more like a football than a basketball. This odd shape causes the light to focus on two points of the retina, rather than one.

Astigmatism is often accompanied by either nearsightedness or farsightedness. If this is the case, both refractive errors can be treated simultaneously. Learn more about astigmatism and the types of astigmatism treatments currently in use.


Presbyopia is an eye condition that comes with age, hindering the up-close focusing ability of the eye. It generally starts affecting patients between the ages of forty and fifty. Presbyopia is currently being treated in a number of ways. Learn more about presbyopia and the latest presbyopia treatment options.

Treatments for Refractive Errors

The three most common refractive errors are myopia (nearsightedness), hyperopia (farsightedness), and astigmatism. These imperfections can be surgically corrected with LASIK eye surgery, custom LASIK, PRK, and other vision correction procedures. Presbyopia, a refractive disorder that comes with age, can be treated with LASIK monovision, the placement of implantable lenses, and conductive keratoplasty.

Higher-Order Aberrations

Many people are familiar with the common eye conditions nearsightedness, farsightedness, and astigmatism. However, most people don't know what higher-order vision aberrations are, despite the fact that they affect the majority of people. An aberration refers to something that deviates from the norm. Lower- and higher-order aberrations distort vision in various ways. Lower-order aberrations such as myopia (nearsightedness), hyperopia (farsightedness), and astigmatism produce blurry vision at near, far, or both distances; higher-order aberrations result in more unique vision problems in patients.

Almost all people are affected by some degree of higher-order aberrations. The symptoms of higher-order aberrations include:

  • Blurry vision
  • Difficulty seeing at night
  • Double vision
  • Ghost images
  • Glare
  • Halos
  • Starburst effect


Higher-order aberrations cannot be diagnosed with traditional eye exams. Your eye doctor must use a wavefront-measuring device to detect and record each patient's unique higher-order aberrations such as comas, trefoils, quadrafoils, and spherical aberrations.

Higher-Order Aberration Treatments

Vision aids such as glasses and contact lenses can treat lower- and higher-order aberrations. If you are seeking a more permanent form of treatment, you can undergo a custom laser vision correction procedure such as LASIK. During custom LASIK treatment, your surgeon will take a wavefront map of the eye; this map then guides the laser in reshaping your cornea to correct lower- and higher-order aberrations. Within a few hours of treatment, patients have significantly improved vision, and most no longer have to use glasses or contact lenses to see clearly.

Locate an Ophthalmologist in Your Area

Millions of individuals have refractive errors that can now be treated with LASIK, implantable contact lenses, and other advances in refractive surgery. If your eyesight is impaired due to myopia (nearsightedness), hyperopia (farsightedness), astigmatism, or presbyopia, contact to a refractive specialist in your area to find out if you are a good candidate for vision correction treatment.

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