Medical names: hyperopia, hypermetropia.
Other common name: longsightedness, long-sight.
Farsightedness is a common vision defect caused by the shape and length of the eye, and may be accentuated by environmental stresses. Farsighted people see distant objects clearly and close objects less clearly. Children with severe farsightedness are a high-risk category for developing crossed-eyes and lazy eye, and should be treated. In adults, problematic, moderate or severe farsightedness should be addressed. Special prescription glasses and contact lenses can correct farsightedness. Laser or incisional procedures are now being used with varying degrees of success to eliminate farsightedness. Orthokeratology and drug therapy are two temporary solutions that can control the symptoms of this defect. The risks associated with these treatments and interventions should be duly noted. Although farsightedness cannot be prevented, proper diagnosis, eye care and monitoring of the condition will bring things back into focus!
What is farsightedness?
Farsightedness is a common vision defect in which distant objects can be seen clearly, while objects that are within close range appear out of focus. People who are farsighted may be able to read street signs from blocks away, but may have difficulty reading a book. Signs of farsightedness include aching, burning, red or tearing eyes, fatigue, headaches, “brow-aches,” poor eye-hand coordination and nervousness or irritability after sustained concentration on close vision work.
You may be farsighted and not even know it! Most people don’t realize they are farsighted until they are in their late 30s, when the ciliary muscles in the eye can no longer compensate for the eye’s natural limitations. Farsightedness is an inherited defect but here is also some evidence showing that environmental factors can accentuate its symptoms.
Most farsightedness occurs because the eye is too short and/or the cornea (the eye’s outer window) too flat. As a result, light rays entering the eye are focused behind, rather than on, the retina (the nerve-rich lining inside the eye, where we “see”) and vision is blurred at close range.
If you are only mildly farsighted, your eye-care specialist may tell you that you do not require corrective eyewear, since your eye muscles may be successfully compensating for your physiological limitations. If you have moderate to severe farsightedness, you will need corrective convex (plus) glasses, or either soft or rigid gas-permeable (RGP) contact lenses in order to maintain clear, strain-free vision.
Laser or conventional surgery can be performed to steepen the curvature of the cornea and focus light precisely on the retina. For optimal results, more than one surgery may be necessary. If successful, these procedures may eliminate the need for eyewear. However, candidates for surgery should bear in mind that correction may not result in perfect 20/20 vision, and prescriptive lenses may still be necessary. The long-term risks associated with these procedures should also be noted. Risks include overcorrection, undercorrection, sensitivity to glare, seeing halos around lights, poor night vision, daily shifts in the ability to focus and increased danger of corneal rupture or scarring, producing permanently clouded vision.
Those looking for an alternative therapy that can temporarily improve farsightedness may prefer orthokeratology. In orthokeratology, a series of special rigid contact lenses are used to realign the cornea. Because studies are ongoing in this area and concern still exists regarding the lack of trials, only limited approval has been received from medical authorities. Possible side effects of orthokeratology include infections and permanent warping or damage to the cornea.
In some cases, “anticholinesterase miotic” drugs may be taken to enhance the focusing mechanisms of the eye. These drugs may be used in children and adults alike in eyedrop or ointment form. It should be noted that headaches, tearing, blurred or clouded vision, decreased night vision and other, potentially serious, side effects are associated with these drugs. For this reason, these drugs should be used as a last resort for persons who cannot or will not wear glasses and in other special cases.
Before any prescription for eyewear or treatment is provided, it is vital to determine the cause of farsightedness. Serious conditions such as diabetes mellitus, intraocular and orbital tumors, inflammations, and neurological or pharmacological causes should be checked for and treated before any prescription or treatment is provided.
Environmental factors play a role in the degree of farsightedness you may develop. So give your eyes a break!
- Keep your work area well-lit and glare-free. Focus on more distant objects every half hour when reading, writing or working on the computer. Ensure your work space is ergonomically designed. And remember to get up and walk around 10 minutes for every 90 minutes of close visual work you do.
- Eat a balanced diet that includes plenty of fruits and vegetables. Make sure you get enough calcium, magnesium, zinc, B-complex vitamins and vitamin C.
- Make stress-reduction techniques, such as stretching, controlled breathing, yoga, meditation and regular low-impact cardiovascular exercise, part of your daily routine.
If you notice any of the symptoms mentioned earlier, see your eye doctor for a complete examination. As you age, you may find that your farsightedness gradually becomes more pronounced. Regular eye examinations will help determine if you need to change the strength of your lenses.
Farsightedness in children
Children under 10 years of age with low to moderate farsightedness but with no tendency to squint and no loss in the sharpness of their vision or other significant problems usually do not require treatment. Vision may improve and correct itself as the eyes continue to grow throughout childhood. But since severe farsightedness in children is closely associated with the development of crossed-eyes (strabismus) and lazy eye (amblyopia), as well as varying degrees of permanent vision loss, treatment for these children is essential. Once diagnosed, eyewear prescriptions for farsightedness may need to be changed to accommodate changes in vision in children during years of rapid growth.
Early detection and monitoring of farsightedness is vital in children. If this defect goes undetected, children’s emotional and social development may suffer as much as their school work. However, routine eye examinations provided by schools may not detect farsightedness. So make sure your child receives a complete eye examination from a qualified eye doctor.
Like newborn monkeys, newborn humans have eyes that are too short (front to back). Since the shortness of our eyes can cause some farsightedness, the majority of children are farsighted at birth.
As babies grow, the cornea flattens and the eye becomes longer so that by 12 months, eyesight has generally significantly clears and between 5 and 10 years of age, most children have normal vision.
Studies with monkeys would suggest that if children get corrective eyewear too early, it may interfere with their eyes' normal growing period. So make sure you see your eye doctor to find out how best to take care of your children’s eyes. If children are only mildly farsighted, you might do better not to monkey around with their vision!
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