What is Astigmatism?
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Eye care specialists employ numerous tests to accurately detect astigmatism and other vision conditions, including visual acuity assessment tests and an instrument called a Keratometer.
Astigmatism is a relatively common eye condition that impairs both near- and distance vision, depending on the shape and function of your eyes and how they bend (refract) light rays.
Astigmatism is caused by an irregular shape of your cornea or lens. Eye care specialists refer to this condition as corneal astigmatism or lenticular astigmatism and its irregular nature prevents light rays from focusing precisely onto your retina in the back of your eye, leading to blurry near and far-sighted vision and strain on the eyes.
Your cornea or lens should typically take the shape of a round ball, allowing light to enter evenly and be focused sharply onto your retina at the back of your eye. But with astigmatism present, light cannot focus on this retina directly; instead it forms two focal points which overlap, leading to blurry vision.
Astigmatism can be hereditary or present from birth, though it may develop following injury, surgery, or certain eye diseases like keratoconus. A comprehensive eye exam with your eye doctor is the most reliable way of diagnosing astigmatism; during your exam they'll use an instrument known as a phoropter to test visual acuity before measuring corneal curvature with something called a corneal topographer.
Eye care specialists can accurately diagnose astigmatism through a series of tests. They'll inspect your cornea and lens (the clear front part of your eye) to see if either has an irregular shape that indicates astigmatism – if they do, this would indicate corneal astigmatism while an unevenly-shaped lens would indicate lenticular astigmatism.
Normal cornea and lens structures should resemble baseballs, allowing light to enter evenly and focus on one focal point on your retina for clear vision. When suffering from astigmatism, however, your eyes may instead take the shape of footballs or eggs; light doesn't focus on one focal point and appears fuzzy and wavy instead.
Astigmatism can often go undetected by children, making regular eye exams starting at age 6 even more essential. Uncorrected astigmatism can negatively impact near and distant vision as well as put children at risk for an eye disorder known as amblyopia if left uncorrected.
Astigmatism may not always be evident, particularly among younger children, but if yours is squinting or rubbing his eyes frequently or has blurry vision it's important to visit an eye care specialist for a full exam. They will inspect every part of their eye (including its interior), perform visual acuity assessments, refraction and cross-cylinder (during which your child will view lenses of various strengths while looking through 360-degree lines for crispest vision) to diagnose astigmatism and provide advice.
Eyeglasses or contact lenses are often an ideal way to correct astigmatism. By bending light rays in such a way that they land directly onto the retina in one focal point, they allow light rays to fall on it correctly and ensure accurate optics. Hard and soft lens options exist with rigid gas permeable (RGP) being more durable and offering improved optics compared to soft lens options. Surgery may also be considered depending on severity; most commonly for astigmatism this is done via laser eye surgery called LASIK.
Astigmatism treatment options include eyeglasses, contact lenses and surgery – depending on what best meets your lifestyle needs and requirements. Your eye care professional can guide you to select one.
Normal eye anatomy involves two perfectly curved surfaces–your lens and cornea–which work together to focus light rays onto the retina for clear vision. However, astigmatism alters these curved surfaces into having irregular curves which lead to blurry or distorted images – one of three common refractive errors along with myopia (nearsightedness) and hyperopia (farsightedness).
Eyeglasses or contact lenses can sharpen your vision by compensating for irregularities in corneal and lenticular curvatures that contribute to astigmatism. Refractive surgery offers another solution. Most commonly performed procedure is LASIK which uses laser technology to reshape corneas; LASEK and PRK procedures apply alcohol directly onto corneas before being reshaped with laser technology.
Eye care specialists employ numerous tests to accurately detect astigmatism and other vision conditions, including visual acuity assessment tests and an instrument called a Keratometer. Astigmatism is a relatively common eye condition that impairs both near- and distance vision, depending on the shape and function of your eyes and how they bend (refract) light rays.…