About 20% of Americans war contact lenses to correct their nearsightedness (myopia), farsightedness (hyperopia) or astigmatisms. Others prefer eyeglasses or refractive surgery. If you have been wearing glasses for a long time, you may not wish to be seen without them, because they have come to form part of what you and other people recognise as your face. They can be, after all, a fashion statement.
One major advantage of contact lenses is the all-round vision they provide, which is especially important for those who practice a sport regularly. You may be surprised to hear that contact lenses have been with us for almost a century. There have been many changes and advances since those early days and the chances are that if in the past you have been told you could not wear contact lenses, this is almost certainly no longer the case, because there are now contact lenses adjusted to fit just about everyone’s needs.To be assessed and fitted for contact lenses, you will need to see an eye care professional (ECP), such as an optician or ophthalmologist, to get a prescription. The kind of thinks an ECP will be assessing you for are your visual needs, the structure of your eye and your tear production.
Lens design and materials vary, as does the length of time you can wear them for. There are basically three types:Hard lenses, made from Plexiglas or Lucite, are all but obsolete because of the kinds of irritations they used to produce. Soft lenses, introduced on the market in 1971, are the most frequently prescribed. They are made from a gel-like substance which is a plastic containing water, and are slightly larger than the iris. More recently, silicon hydrogel contact lenses have become available. These are the preferred choice for ECPs, because they allow for a better supply of oxygen to the eye and do not cause dehydration. The lens of choice for presbyopia and high stigmatism are RGP lenses, made from rigid plastics, which are oxygen permeable. At about 8mm diameter they are smaller than your iris.
People used to have to take their contact lenses out at night, but since the introduction of extended wear in 1979, this is no longer the case. There are now three kinds of lenses, daily wear and extended wear, which can be worn up to seven days in a row, plus continuous wear, which can be kept n for a month at a time.
The reason contact lenses need replacing regularly is that tears naturally contain lipids and proteins. These can adhere to the lens, forming a build-up which can cause irritation and even lead to infection.Ocular hygiene helps and there are very good cleaning products for this purpose. Nevertheless, eventually the lenses will need replacing. So-called disposable lenses take care of this, whether they are replaced every day, once a week or every two weeks, or monthly. If you go to contact-lenses-reviews you will be able to find more information about contact lenses.
One final point is that bifocal and tinted contact lenses are also available. Your EPC will assess your vision and advise you on which kind of lens would be best for you.
Kelly Hunter operates contact-lenses-reviews and writes about Contact Lenses.