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The Multifocal Contact Lens: Is It for You?
It's a little-known fact that contact lenses can be bifocal, multifocal, or even progressive. But a multifocal contact lens can be the perfect solution for middle-aged eyes affected by presbyopia, the slow hardening of the lens combined with weakening of the muscles around the pupil that makes it difficult to focus on objects closer than arm's length. Why would you get multifocal contacts? Wouldn't granny glasses work just as well? The fact is, most people who develop presbyopia after the age of 40 make do with reading glasses or bifocals, but consider this: Reading glasses are a hassle. For reading glasses to work, you have to put them on. Because they interfere with distant vision, when you finish reading, you have to take them off. You have to carry them everywhere, and they are easy to misplace. Many people wind up buying several pairs of reading glasses for home, the office, and a spare for the glove compartment, briefcase, or purse. Moreover, Reading glasses make you look old. Bifocals, especially if they have round or rectangular segments for near vision, label you as definitely over 40. And although no-line progressive lenses look better, they still hide your eyes from the world. Moreover, progressive lenses distort your vision to the left and right. And, if you use sunglasses, you have to pay for a second, expensive prescription. Your solution may be a multifocal contact lens. Multifocals are available as both hard and soft lenses, and they are available for both extended wear and one-time use. There are some limitations, however, in your choices between hard and soft lenses.
Hard, or rigid gas permeable (RGP or GP The top of the lens corrects for distant vision, and some portion of the bottom on the lens corrects for near vision. Between these two zones there is an almost invisible line that helps the dispensing optician, optometrist, or ophthalmologist make sure the lens fits properly. When you look forward through a lens with an alternating image design, your distant vision is corrected. When you look downward through an alternating image design, your near vision is corrected. The advantage of this design is your brain does not have to sort out what clear images are from fuzzy images. You can simply look up or down if something looks out of focus. However, you may have some trouble seeing near objects in the periphery of your vision, if they are placed in front of you to the left or to the right. The concentric design compensates for this limitation. Available for both hard and soft lenses, the concentric design has concentric rings of correction, usually a ring for distance vision in the very center of the lens, surrounded by a ring for intermediate vision, and with a ring for near vision on the outside of the lens. This configuration makes it easy to see objects to the right or left placed in front of you on your desk. However, it gives you all kinds of vision correction when you look straight ahead. Your brain has to be able to sort out clear and fuzzy images, and you may need to learn to turn your head left to right to see any particular object in its greatest clarity. Multifocal contact lenses don't always work out. If you need to return your lenses, chances are you can get a refund for the lenses themselves, but not for the eye exam or fitting. However, for 90 per cent of people 90 per cent of the time, multifocal lenses are the perfect prescription for presbyopia correction and freedom from glasses in daily life. |