Contact Lenses
Contact lenses are one of the miracles of modern technology. Today, more than three million people in the UK enjoy the clear, natural and unobstructed vision offered by contact lenses which don’t fog up or get splashed with rain as glasses sometimes can.
New lens designs and materials, as well as advanced care products, now make contact lenses easier and more comfortable to wear than ever before. They offer freedom from wearing glasses in daily life, when playing sport, or for that important social occasion, and can bring particular benefits for individuals with stronger vision correction requirements.
Are contact lenses right for me?
Major advances in contact lens design mean that almost everyone can wear contact lenses successfully nowadays. People of all ages can be fitted, although special care is needed for the very young and elderly.
Common eyesight defects, such as short-sightedness and long-sightedness, are easily corrected with contact lenses, but now conditions such as astigmatism and presbyopia can also be treated very effectively with contact lenses.
In the past, people with astigmatism, a condition in which the eye is irregularly shaped causing distorted vision, were restricted to wearing glasses, but today’s ‘toric’ contact lenses can be custom made for each individual to provide clear vision. Presbyopia, the ageing of the eye’s lens which progressively affects everyone over the age of about 40, makes it difficult to shift focus between near and distant objects. This condition can also be corrected with bifocal contact lenses which provide claer distance and near vision.
As contact lenses are worn next to the eye, there is nothing to obstruct your peripheral vision in the way that spectacle frames can. Also, the lenses move with your eye, meaning that you are always looking through the centre of the lens, where vision is best. In the majority of cases, people actually see better with contact lenses than they would with glasses.
What should I do if I want to try contact lenses?
Before you can wear contact lenses you must have your eyes fully examined. Most eyecare practitioners are qualified to dispense contact lenses, but if your practitioner is not he will be able to advise you of a practitioner who is.
During the examination your eyes will be tested to determine the strength of lenses you will need for clear vision, and the health of you and your eyes and eyelids will be examined. The quality of your tears, needed for lubrication of contact lenses – will also be assessed. Then, the curvature and diameter of the cornea at the front of your eye will be measured, together with the size of your pupils and the positions of your eyelids.
Based on this information, your practitioner will be able to advise you about the most suitable contact lenses.
What types of contact lenses are available?
Hard lenses The first contact lenses were what have become known as ‘hard’ lenses. These are made of a perspex material which, while very durable, does not allow essential oxygen to pass through to the surface of the eye. Although still available for certain specialist needs, they have been largely replaced by gas permeable lenses which allow good oxygen flow and enable the eye to ‘breathe’.
Rigid gas permeable (RGP) lenses
Rigid gas permeable lenses allow oxygen to pass to the surface of the eye, but they are made of firmer plastics than soft lenses. This makes them more durable and gives them a longer life span. These lenses are particularly suitable for certain prescriptions such as high degrees of astigmatism, where they give very good vision. Some people find rigid lenses easier to handle than soft lenses and, although they take a little longer to get used to, regular wearers find them very comfortable.
Soft lenses
Modern soft contact lenses are made from gel-like plastics, often with a high water content, that allow oxygen to pass freely to the eye. Because of this, soft lenses can be made much larger which in turn makes them very comfortable and easy to adapt to. Some of the new ultra-thin soft lenses are so comfortable that new wearers can leave them in all day right from the start. New users usually find that they are only mildly aware of standard thickness soft lenses and that tolerance can be built up fairly easily so that most people are able to wear them all day within a week.
Disposable lenses
All types of contact lenses are now available on a planned replacement programme. New manufacturing techniques have made it possible for users to have a fresh pair of lenses regularly for about the same cost over a period as non-disposable lenses. Daily disposable lenses are becoming increasingly popular as they eliminate the need for a lens care routine, but depending on the type of lens and the environment in which it will be worn, the replacement period can be anything from one day to two years.
Extended wear lenses
Most contact lenses are worn on a daily basis, being removed in the evening and put back in next morning. Special extended wear soft lenses are now available which may be recommended by your practitioner, which allow you to sleep in them. Typically they are replaced weekly or monthly.
Tinted lenses
Exciting tinted contact lenses which can enhance or even change the colour of your eyes without affecting what you see are now widely available.
Are contact lenses difficult to insert and remove?
No. Many people are worried about putting a lens in for the first time, but simple techniques have been developed which make insertion and removal of contact lenses quite easy. When you get your lenses you will be taught the correct method.
Caring for your lenses
Developments in lens care products have now made it easier than ever to keep your contact lenses clean, comfortable and safe from harmful bacteria. These three simple steps should result in trouble-free use:
If in any doubt, always seek advice from your practitioner.
New lens designs and materials, as well as advanced care products, now make contact lenses easier and more comfortable to wear than ever before. They offer freedom from wearing glasses in daily life, when playing sport, or for that important social occasion, and can bring particular benefits for individuals with stronger vision correction requirements.
Are contact lenses right for me?
Major advances in contact lens design mean that almost everyone can wear contact lenses successfully nowadays. People of all ages can be fitted, although special care is needed for the very young and elderly.
Common eyesight defects, such as short-sightedness and long-sightedness, are easily corrected with contact lenses, but now conditions such as astigmatism and presbyopia can also be treated very effectively with contact lenses.
In the past, people with astigmatism, a condition in which the eye is irregularly shaped causing distorted vision, were restricted to wearing glasses, but today’s ‘toric’ contact lenses can be custom made for each individual to provide clear vision. Presbyopia, the ageing of the eye’s lens which progressively affects everyone over the age of about 40, makes it difficult to shift focus between near and distant objects. This condition can also be corrected with bifocal contact lenses which provide claer distance and near vision.
As contact lenses are worn next to the eye, there is nothing to obstruct your peripheral vision in the way that spectacle frames can. Also, the lenses move with your eye, meaning that you are always looking through the centre of the lens, where vision is best. In the majority of cases, people actually see better with contact lenses than they would with glasses.
What should I do if I want to try contact lenses?
Before you can wear contact lenses you must have your eyes fully examined. Most eyecare practitioners are qualified to dispense contact lenses, but if your practitioner is not he will be able to advise you of a practitioner who is.
During the examination your eyes will be tested to determine the strength of lenses you will need for clear vision, and the health of you and your eyes and eyelids will be examined. The quality of your tears, needed for lubrication of contact lenses – will also be assessed. Then, the curvature and diameter of the cornea at the front of your eye will be measured, together with the size of your pupils and the positions of your eyelids.
Based on this information, your practitioner will be able to advise you about the most suitable contact lenses.
What types of contact lenses are available?
Hard lenses The first contact lenses were what have become known as ‘hard’ lenses. These are made of a perspex material which, while very durable, does not allow essential oxygen to pass through to the surface of the eye. Although still available for certain specialist needs, they have been largely replaced by gas permeable lenses which allow good oxygen flow and enable the eye to ‘breathe’.
Rigid gas permeable (RGP) lenses
Rigid gas permeable lenses allow oxygen to pass to the surface of the eye, but they are made of firmer plastics than soft lenses. This makes them more durable and gives them a longer life span. These lenses are particularly suitable for certain prescriptions such as high degrees of astigmatism, where they give very good vision. Some people find rigid lenses easier to handle than soft lenses and, although they take a little longer to get used to, regular wearers find them very comfortable.
Soft lenses
Modern soft contact lenses are made from gel-like plastics, often with a high water content, that allow oxygen to pass freely to the eye. Because of this, soft lenses can be made much larger which in turn makes them very comfortable and easy to adapt to. Some of the new ultra-thin soft lenses are so comfortable that new wearers can leave them in all day right from the start. New users usually find that they are only mildly aware of standard thickness soft lenses and that tolerance can be built up fairly easily so that most people are able to wear them all day within a week.
Disposable lenses
All types of contact lenses are now available on a planned replacement programme. New manufacturing techniques have made it possible for users to have a fresh pair of lenses regularly for about the same cost over a period as non-disposable lenses. Daily disposable lenses are becoming increasingly popular as they eliminate the need for a lens care routine, but depending on the type of lens and the environment in which it will be worn, the replacement period can be anything from one day to two years.
Extended wear lenses
Most contact lenses are worn on a daily basis, being removed in the evening and put back in next morning. Special extended wear soft lenses are now available which may be recommended by your practitioner, which allow you to sleep in them. Typically they are replaced weekly or monthly.
Tinted lenses
Exciting tinted contact lenses which can enhance or even change the colour of your eyes without affecting what you see are now widely available.
Are contact lenses difficult to insert and remove?
No. Many people are worried about putting a lens in for the first time, but simple techniques have been developed which make insertion and removal of contact lenses quite easy. When you get your lenses you will be taught the correct method.
Caring for your lenses
Developments in lens care products have now made it easier than ever to keep your contact lenses clean, comfortable and safe from harmful bacteria. These three simple steps should result in trouble-free use:
- Clean your contact lenses daily
This will remove dust, pollution, make-up and other things that may accumulate on the lens in daily wear. - Disinfect your contact lenses dailyDisinfecting your lenses will ensure they are free from any micro-organisms still on the lens after cleaning.
- Weekly protein removal
This breaks down protein deposits that are produced naturally in everyone’s tears. If you don’t do this the performance and life of the lens could be reduced. Your practitioner will advise as to the necessity and frequency of this routine.
If in any doubt, always seek advice from your practitioner.
http://www.eyecaretrust.org.uk/view.php?item_id=115
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