Presbyopia is a vision in which they make clear the eyes are not in a position sharply on close objects. It usually begins after the age of about forty years ago, when you restart the lenses into the eye reduce the flexibility. Presbyopia affects about 90 million adults in the U.S. alone and about one quarter of patients will be through the door an ophthalmologist suffer.
Symptoms of presbyopia have difficulty reading, difficulty seeing in low light conditions and sometimesHeadaches.
Typically, these problems have been addressed with vision to be the old-fashioned reading glasses. Or existing eyeglass wearers can opt for bifocal eyeglasses. However, the use of modern contact lenses for use with presbyopia has some distinct advantages over their cosmetic appeal. For example, they can also suitable for other aspects of lifestyle, a carrier such as sports, exercise, or the use of a computer.
Recently, contact lensesfor the correction of presbyopia have conveniently types such as disposable or frequent replacement types. Today, these are very popular lens types are obvious advantages for the wearer.
HOW lenses to correct presbyopia
From a technical perspective, there are three different ways, can be used by the contact lenses to correct presbyopia, each with advantages and disadvantages for certain patients. ButIt is important that there is a choice, and each carrier is probably a method best suited to their unique situation are. The various methods of contact lenses are as follows:
Monovision
The monovision technique with one eye a lens for seeing near objects, and in the other eye, a lens to see distant objects. Many people find that monovision works very well for them. It relies on the ability of the brain, from process and to combine specific informationthe best available sources to deliver the clearest possible vision. In some cases, the ophthalmologist may employ a Bifocal lens in one eye and a normal distance lens in the other. The main problem associated with monovision is the apparent loss of depth of vision in some patients.
BIFOCAL CONTACT LENSES
As with traditional bifocal eyeglasses, each lens in bifocal contact lenses have two powers - one for seeing near objectsother for distant objects. Some types of bifocal lenses when magnified look a little like a cross with a central inner zone surrounded by the outer zone. The disadvantage of this type of lens that could, under certain conditions in the reduced lighting, the vision is not always as sharp in certain areas.
MULTIFOCAL LENSES
Multifocal contact lenses work very much like the progressive lenses for eyeglasses. These lenseshave several zones of different power to support the eye, as after the focus changes to different objects at different distances. Therefore, these lenses are designed for the vision at near, intermediate and distant objects work. Its disadvantages are generally the same as for bifocal contact lenses, with occasional loss of visual acuity.
Bifocal lenses are translating into two basic design types are available, "and" simultaneous ", theessential characteristics, as follows:
TRANSLATE bifocal lenses
Another name for the translation of lens is an "interaction lens". Regular gas permeable bifocal lenses of this type. Their use is very similar to the traditional bifocal eyeglasses. The carrier is through a zone for distance then look to "translate" to look through the other zone for the close. Both zones are not seen by the sameTime.
SIMULTANEOUS bifocal lenses
The majority of bifocal soft contact lenses on the market by the concurrent "type. As the name implies, actually, while the lens wearer sees through the various powers of the lenses at the same time. What happens is that the brain steps and suppressed "power and powers that are not necessary at this particular time in order to see clearly. There are other subdivisions of this lens type, but we do not go into details in this brief overview.
As with all contact lens selection and wear, choosing the right type of Bifocal lens depends as much on unique lifestyle of the wearer when his unique vision characteristics. For example, a patient who is regularly required to sports different needs, only one needs to have socially wear or for use in the workplace.
But the success of the adoption of bifocal contact> Lenses is very much on the expectations of the institution who should know that almost by definition, bifocal lenses much a compromise, and that he or she will never be the visual acuity in all environments and again that they had when younger. In most cases this is perfectly acceptable, and bifocal lenses have now earned their place in the ophthalmologist's ever-expanding repertoire.
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