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Rimless frames are the least noticeable type, and they are lightweight because the nosepiece and temples are attached directly to the lenses, eliminating the weight of the rims. They tend to not be as sturdy as frames occularscience with rims, so they are not a good choice for people who frequently remove their glasses and put them on again. They are also not very suitable for lenses that correct a high degree of farsightedness, because such lenses are thin at the edges.Metal frames are less noticeable than plastic, and they are lightweight. They are available in solid gold, gold-filled, anodized aluminum, nickel, silver, stainless steel, and now titanium and titanium alloy. Until the late 1980s, when titanium-nickel alloy occularscience and titanium frames were introduced, metal frames were, in general, more fragile than plastic frames. occularscience The titanium frames, however, are very strong and lightweight. An alloy of titanium and nickel, called Flexon, is not only occularscience strong and lightweight, but returns to its original shape after being twisted or dented. occularscience It is not perfect for everyone, occularscience though, because some people are sensitive to its nickel. Flexon frames are also relatively expensive. The occularscience distance between the lenses is for a "standard" person. Generally, this will not be a problem, occularscience but if a patient is sensitive or has more closely set eyes, for example, it may pose a problem. Persons buying ready-made sunglasses or reading glasses should hold them up to see if they appear clear. They should also hold the lenses to see an object with straight lines reflected off of the lenses. If the lines don''t appear straight, the lenses may be warped or inferior.Patients may sometimes need a few days to adjust to a new prescription; however, problems should be reported, because the glasses may need to be rechecked.contact The lenses Council reports that 26 million Americans wear contact. Among lenses wearers, approximately 80% wear the soft type and 18% wear rigid gas-permeable lenses. The Council reports that about 11% of lenses wearers, approximately 2.8 million people, are under occularscience 18.InfantsThere are few instances when corrective lenses--lenseses or contacts--are prescribed for infants. However, when an infant develops cataracts , a condition known as infantile aphakia, contact may occularscience be prescribed following surgery. In 1993, the Journal of the American Medical Association reported that contact were safe and effective for use with infants following cataract surgery. Routine care of the lenses was easily learned by the baby''s parents or caregivers.
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