Q:

What is astigmatism in the eyes?

A:

Quick Answer

Astigmatism is a condition that causes blurred vision when the lens or cornea of an eye has an irregular surface contour, according to Mayo Clinic. Rather than having a consistently smooth curvature, an astigmatic lens or cornea has abnormal curves and flattened areas, changing how the eye processes light.

 Know More

Full Answer

As light passes into the eye, the cornea and lens work together to focus incoming rays toward the retina and produce a clear image, explains the American Optometric Association. Shape irregularities can change how different sections of the cornea or lens surface refract light, distorting the eye's focal point. For example, the corneal surface may be oval-shaped instead of spherical. If the condition is not present at birth, it may develop after a surgery or injury.

Astigmatism is known as a refractive error, and physicians usually classify it as corneal or lenticular, notes Mayo Clinic. Blurriness caused by refractive distortion occurs in the same direction as the abnormal curvature, such as vertically, horizontally or diagonally. In addition to vision problems, people with astigmatism may develop headaches or eye strain.

Serious cases are often accompanied by myopia, known as nearsightedness, or hyperopia, known as farsightedness, according to Mayo Clinic. In a nearsighted eye, an excessively curved cornea shortens the point of focus, making far off objects seem blurry. In farsighted vision, a cornea lacking curvature or an unusually short eye makes the point of focus longer than normal, so closer objects appear blurry.

Learn more about Vision

Related Questions

  • Q:

    How is cataract surgery done?

    A:

    During cataract surgery, a small incision is cut on the side of the cornea, and a device that emits ultrasound vibrations is inserted into the eye to break the cloudy lens known as the cataract, which is ultimately removed. A clear lens is then inserted to replace the cloudy lens.

    Full Answer >
    Filed Under:
  • Q:

    What causes a bubble to form on the white of the eye?

    A:

    A blister or bubble that forms on the white of the eye signifies allergic conjunctivitis, a condition in which the eyes react to irritants such as pollen, dust and dander, according to the American Association for Pediatric Ophthalmology and Strabismus. The condition is not contagious but can cause significant discomfort.

    Full Answer >
    Filed Under:
  • Q:

    What is LASIK for astigmatism?

    A:

    LASIK surgery for astigmatism is a form of eye surgery that reshapes the inner portion of the cornea to correct the astigmatism. It is effective for individuals with mild to moderate levels of astigmatism.

    Full Answer >
    Filed Under:
  • Q:

    What is the path of light through the eye?

    A:

    According to The Merck Manual Home Health Handbook, light travels through the sclera, cornea, pupil and lens before stopping at the retina, respectively. Once at the retina, the information from the light is converted to electrical impulses for the brain to interpret.

    Full Answer >
    Filed Under:

Explore