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Ocular terminology can be very confusing. When your optometrist diagnoses you or your family members with future vision, that is usually the end of the explanation. Far vision can create so many different effects on your vision that it may not even appear to be a visual condition. Farsightedness (farsightedness) generally results in good distance vision, with problems induced by near tasks such as reading and working on the computer. It’s a somewhat confusing term, as farsightedness is actually an optical error of distance vision, while symptoms are more common when you use near vision.

To further complicate the situation, if your optometrist finds that your eye prescription is extremely farsighted, you will not see clearly up close or far. If you are young and have a low or moderate degree of hyperopia, your vision may be clear at all distances. It’s no wonder that people have trouble understanding the concept of farsightedness and why ophthalmologists often avoid trying to explain it. Fortunately, there is a muscle called the ciliary muscle that surrounds the lens of the eye and is attached to the lens with tiny fibers. Active contraction of this muscle loosens tension on the lens of the eye and increases the focusing power of the eyes. At lower amounts of farsightedness, if you are under the age of forty, the eye’s focusing ability can adapt to farsightedness and clarify your vision both far and near. Ophthalmologists use the words focus and accommodation interchangeably to indicate that the eye muscle has been put to work to increase the eye’s power for near vision.

Even lower amounts of farsightedness have been shown to interfere with reading in some children and adults, but typically two to three prescription units begin to create visually related symptoms. Children and adolescents have a large number of adaptations and sometimes very large prescriptions for farsightedness are not noticed because they can clear near and far vision when focusing. They will often suffer from headaches and an unconscious aversion to reading due to eye strain and the constant effort required to maintain clear vision. As we age, we gradually lose the ability to concentrate. This degradation of focus begins between the ages of fifteen and twenty, but affects distances so close at first that we never realize it because we don’t use our vision an inch or two away.

People who are farsighted have a different type of problem than people who are nearsighted. They have to constantly focus to keep their distance vision clear, and as objects get closer they have to increase their focusing efforts even more. This is not a problem if you are young and have a lesser amount of farsightedness, but as you get older or more farsighted, the extra effort you put in begins to show itself. This occurs initially with reading and computer use, due to the added effort of focusing above the amount required for distance. In high-tech areas like northern Colorado, there is a higher percentage of the population who use computers all day, and optometrists see more symptoms of farsightedness. Uncorrected distance vision can be an important component of computer vision syndrome. Often times, ophthalmic patients will be prescribed eyeglasses or contact lenses for close-up work that only correct the far-out amount of farsightedness. This reduces the amount of focus required for levels close to normal. The normal effort remaining to read or work on a computer rarely creates visual discomfort. This is another reason why your optometrist may not tell you much about your vision for the future. It is difficult for them to explain why they recommend a prescription for distance glasses when you only have near problems.

As farsighted optometry patients reach their forties, they find that they have gradually started wearing glasses all the time. Many people mistakenly believe that wearing glasses has weakened their eyes and sometimes feel that their ophthalmologist has made them dependent on glasses. This is an incorrect assumption, as the loss of accommodative ability would have occurred without the use of glasses and would have been a problem at a younger age in the absence of corrective glasses. This loss of power of focus is a visual condition specified as presbyopia, which patients often mistake for farsightedness. Although it progresses from a young age as explained above, it is only diagnosed when you reduce your ability to focus, so you cannot see at about sixteen inches, the average reading distance.

Optically, the farsighted eye is usually too short and light is focused behind it rather than on the retina for distance. There may also be individual components of the eye that are too weak to focus vision properly. The lens may be underpowered, or the clear corneal tissue in the front of the eye may curve slightly less than normal. A lens with positive or positive power is used to correct farsightedness. This is a thicker lens in the middle and thinner around the edges, like a biconvex lens. The best optical design for clear central and peripheral vision is a lens that is more curved in the front and even more forward curved in the back, only to a lesser degree. This results in a lens with a center that is relatively far from the front of the eye, with a bulky appearance.

As an ophthalmic lens used for farsightedness moves away from the eye, the eye appears larger, as does the effect of moving a magnifying glass away from an object. This also increases the size of the image that the eye sees. Advanced optical designs have eliminated the resulting type of insect eye appearance through the use of aspherical lens designs. Aspherical lenses start with a spherical front lens surface in the center (like the curve of a tennis ball), then the curvature gradually tapers or flattens toward the edge of the lens. This is the traditional design that has an accompanying spherical curvature on the rear surface of the lens. Newly released free-form lens technology allows aspherical lens curves to be rectified on the back surface of a lens. These lenses are very sophisticated designs that use different degrees of asphericity on different tangential lines to compensate for astigmatism in your prescription.

Either way, the flattened lens design allows the lenses to sit closer to your eyes, reducing magnification or bug-eye effect. The aspherical design due to the complex peculiarities of the optics also counteracts various forms of optical aberrations (blurred vision) that normally occur when looking to the side of a spherical lens with a flatter lens design. A common misconception is that aspherical lenses improve vision. They do not significantly improve vision, but allow for a thinner, lighter, and more cosmetically attractive lens with less magnification. The aspherical design allows these improvements to be achieved without compromising clear peripheral vision. The lenses available to your ophthalmologist have seen quantum advances in the last five years, probably equivalent to all the advances made in the previous fifty years. Lens design improvements are beginning to resemble computer chips that double in capacity every eighteen months. The future of eyewear has never been brighter!

Some facts about farsighted eyes:

  • Some people are farsighted in one eye and nearsighted in the other. If the amounts are correct, they can see near and far without bifocals.
  • President James Buchannan was farsighted in one eye and nearsighted in the other (and had a tic in his eye).
  • President Harry Truman was farsighted.
  • Latent farsightedness occurs when a child has compensated with a sustained focus for distance for so long that they cannot relax their eyes for a true prescription reading. Only checking the eyeglass prescription after the special eye drops have eliminated the focus ability of the eyes can produce an accurate reading of the prescription.
  • Ohio State University has started a study to see if providing prescriptions that are not strong enough for extremely farsighted babies will help the eyes correct themselves.
  • The eyes tend to become slightly more farsighted (or less myopic) between the ages of 40 and 50.
  • Young or middle-aged men can develop fluid swelling in the central retina and become farsighted as a direct result of stress.
  • Children with farsightedness tend to have farsighted brothers and sisters, but not necessarily parents with the eye condition.
  • About one in four people are farsighted, but the number is slowly decreasing as the prevalence of nearsightedness increases.

Contact lenses can be very helpful in correcting farsighted eyes for a number of reasons. Unlike glasses that arch away from the eye, contact lenses are placed directly on the surface of the eye and therefore provide very little magnification effect. When you wear contact lenses, you are always looking through the optical center of the lens, which is the maximized point for good vision. This is due to the fact that contact lenses move with the eye when looking sideways. With glasses, you can see through the lens at an angle when you turn your eyes, and this creates optical aberrations that degrade your vision. These benefits often make contact lenses the primary choice for corrective glasses for higher amounts of farsightedness in children and adolescents. This is often a time when your appearance is extremely important to your self-esteem. Who doesn’t want to look better, especially when the old alternative was bug eye magnifying glasses that weighed a ton and constantly slid down the nose?

Eye exams are valuable in detecting prescription eye problems, but farsightedness is often lost because children have a great ability to focus and pass the 20/20 test. Only a comprehensive eye exam by your ophthalmologist can ensure that your children and adolescents have the correct eye prescription for efficient reading and learning in school. Schedule today for an annual vision checkup. And don’t forget the new options you have as a forward-thinking adult.

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