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Contact lenses unquestionably represent a major advance in the
area of non-surgical vision correction leaving glasses way behind.
Indeed today, in contrast to contacts, glass spectacles look
like prehistoric artifacts. Unfortunately, the benefits of contacts
still remain unrealized in some quarters because of what they
were once.
Modern contacts offer you better vision, more comfort, far fewer
problems and are much easier to look after. They come in varieties
to suit almost all individuals. They were pricier, but today the
average pair of spectacles would set you back more than contact
lenses.
Why swap glasses for contacts?
- To retain your original and natural looks. Glasses do
change the appearance. In fact with contacts, you also seem
natural to yourself. Contact lenses are just like new eyes in
many ways.
- To get the burden and the pressure off your nose,
cheeks and ears that coems form wearing glasses. Plus glasses
become cloudy
requiring
frequent cleaning. And that’s one hassle you could very
well do without.
- Contacts allow you to play any sport and give
it 100% without the nagging fear of your glasses falling off.
Don’t believe
the myth that contacts fall off or irritate the eye. They do
neither of these.
Contacts offer you freedom from glasses not to be scoffed at
if you’ve read the preceding section well.
How do contacts help?
They correct all types of vision problems that glasses correct.
Plus some kinds of astigmatism that glasses cannot correct.
What are the types of contact lenses?
A critical property of contact lenses is their gas permeability,
which allows oxygen to flow through them. Oxygen is vital for
good eye health. Higher the gas permeability more is the quantity
of oxygen that the eye receives.
Today a variety of contact lenses are available made from different
types of plastic material but can be grouped under two categories.
These are the hard or rigid gas permeable (RGP) lenses and soft
contact lenses.
RGP lenses: RGP lenses are harder and do not contain water. They
are less flexible than soft contacts and so little uncomfortable,
but only initially. However, their gas permeability is higher,
causing fewer problems. They can correct more vision problems
including astigmatism. On the whole, compared to soft contacts,
RGP lenses last longer, need less frequent replacement, are less
likely to cause infections and are easy to look after.
Soft contacts: Soft contact lenses have higher water content
and types include:
- Daily wear contacts are worn by most people who use contacts.
They need to be inserted every morning and removed every night
before going to bed.
- Disposable contacts are used for specific
periods, depending on their construction, and then discarded.
The period could range
from one day to a month. Most doctors recommend seven to fourteen
days wear. Disposables have proved to be the safest and least
prone to infections.
- Extended wear contacts are worn continuously
from 7 up to 30 days. Since extended wears are meant for wear
even during sleep, they
are made from super permeable materials, which allow more
oxygen to reach your eyes. However, the long periods of wear
can cause
more problems.
Don’t they cause problems?
They can but all good things come at a price. Any foreign body
implanted in us will set off some adverse reactions. With contacts
the eye faces two main problems.
The first one concerns corneal infections. Contacts, which cover
the eyes, reduce the normal flow of oxygen producing these complications.
The earliest glass contacts hardly allowed any oxygen to reach
the eye causing many problems. Modern contact lenses are much
more gas permeable. But the oxygen received still remains reduced
and will remain so, at least for the foreseeable future, since
contacts will always remain a barrier to normal supply of oxygen.
Secondly, lenses, to some extent, obstruct eye movements reducing
tear production and flow. Tears keep the eye clean. Lenses therefore
cause unremoved debris to collect under the lens causing infections.
Lens care
Three quarters of the lens wearing population are free of any
complications, but that leaves one quarter of wearers who experience
one or more of the above adverse consequences of contact lens
wear at some point.
Better lens care can prevent a lot of eye problems. Studies have
shown that improper lens care is the direct cause of many such
problems. Proper lens care regime prescribed by the doctor, as
also his other instructions, is the price you pay for wearing
contact lenses.
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