Resources

  • Astigmatism

    Astigmatism is a vision condition that causes blurred vision due either to the irregular shape of the cornea, the clear front cover of the eye, or sometimes the curvature of the lens inside the eye. An irregular shaped cornea or lens prevents light from focusing properly on the retina, the light sensitive surface at the back of the eye. As a result, vision becomes blurred at any distance.

    Astigmatism is a very common vision condition. Most people have some degree of astigmatism. Slight amounts of astigmatism usually don’t affect vision and don’t require treatment. However, larger amounts cause distorted or blurred vision, eye discomfort and headaches.

    Astigmatism frequently occurs with other vision conditions like nearsightedness (myopia) and farsightedness (hyperopia). Together these vision conditions are referred to as refractive errors because they affect how the eyes bend or “refract” light.

  • Hyperopia

    Farsightedness, or hyperopia, as it is medically termed, is a vision condition in which distant objects can be seen clearly, but close ones do not come into proper focus. Farsightedness occurs if your eyeball is too short or the cornea has too little curvature. In these cases, your eye can’t correctly focus the light that enters it.

    Common signs of hyperopia include difficulty concentrating and maintaining a clear focus on near objects, eye strain, fatigue and/or headaches after close work, aching or burning eyes, and irritability or nervousness after sustained concentration.

    Common vision screenings, like the ones done in schools, often don’t detect hyperopia. However, a comprehensive optometric examination will include the necessary testing to diagnose hyperopia. If needed, your optometrist can offer treatment options.

    In mild cases of farsightedness, your eyes may be able to compensate without corrective lenses. In other cases, your optometrist can prescribe eyeglasses or contact lenses that alter the way the light enters your eyes, allowing you to clearly see close objects.

     

  • Myopia

    Nearsightedness, or myopia, as it is medically termed, is a vision condition in which close objects are seen clearly, but objects farther away appear blurred. Nearsightedness occurs if the eyeball is too long or the cornea, the clear front cover of the eye, has too much curvature. As a result, the light entering the eye isn’t focused correctly and distant objects look blurred.

    Nearsightedness is a very common vision condition affecting nearly 30 percent of the U.S. population. Some research supports the theory that nearsightedness is hereditary.  There is also growing evidence that it is influenced by the visual stress of too much close work.

    Generally, nearsightedness first occurs in school-age children. Because the eye continues to grow during childhood, it typically progresses until about age 20. However, nearsightedness may also develop in adults due to visual stress or health conditions such as diabetes.  Visit our myopia control page to learn new ways to control the progression of myopia.  

    A common sign of nearsightedness is difficulty with the clarity of distant objects like a movie or TV screen or the chalkboard in school. A comprehensive optometric examination will include testing for nearsightedness. An optometrist can prescribe eyeglasses or contact lenses that correct nearsightedness by bending the visual images that enter the eyes, focusing the images correctly at the back of the eye.

    Depending on the amount of nearsightedness, you may only need to wear glasses or contact lenses for certain activities, like watching a movie or driving a car. Or, if you are very nearsighted, they may need to be worn all the time.

  • Presbyopia

    Presbyopia is when your eyes gradually lose the ability to see things clearly up close. It is a normal part of aging. In fact, the word “presbyopia” means “old eye” in Greek. You may start to notice presbyopia shortly after age 40. You will probably find that you hold reading materials farther away in order to see them clearly.

    Your clear lens sits inside the eye behind your colored iris. It changes shape to focus light onto the retina so you can see. When you are young, the lens is soft and flexible, easily changing shape. This lets you focus on objects both close-up and far away. After age 40, the lens becomes more rigid. It cannot change shape as easily. This makes it harder to read, thread a needle, or do other close-up tasks.

    There is no way to stop or reverse the normal aging process that causes presbyopia. However, presbyopia can be corrected with eyeglasses, contact lenses or surgery. If you do not correct presbyopia, you may be bothered by headaches and eye strain.