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Contact Lenses
The following is a description of the various types
of contact lenses available.
HARD CONTACTS
*PMMA - this is the oldest type of contact lens
available. It is no longer used for new contact lens wearers because
the material does not allow oxygen to flow through it, thus depriving
the cornea of most of it's oxygen supply and creating a potential
health risk.
*RIGID GAS PERMEABLE - these are the new hard
contacts. They allow a substantial amount of oxygen to pass through
the lens for the cornea to use. A person can feel gas permeable
contacts in their eyes slightly more than soft contacts, and they
can move around or come off the eye during very physical activities.
However, these contacts are more durable and do not wear out as
quickly as soft contacts. They frequently afford better vision for
persons with astigmatism.
SOFT CONTACTS
*CONVENTIONAL - these contacts are usually worn
for up to a year before replacing them. They are not commonly used
anymore since they require more maintenance and pose more health
risks than the newer styles of soft contact lenses.
*PLANNED REPLACEMENT - these are contacts that
are usually thrown away every one to three months. They are commonly
used and require very little maintenance and have a low health risk.
Their slight increase in cost over conventional contacts is usually
justified by their increased comfort and convenience.
*DISPOSABLE - this type usually represents the
most popular contact worn - the two week disposable lenses. They
are very safe and almost maintenance free. The small additional
cost for wearing fresh contacts every two weeks is usually a good
investment.
*ONE DAY DISPOSABLE - these are the ultimate
lenses for convenience and safety. Each pair of contacts are thrown
away at the end of the day with a new pair worn the next day. These
are especially beneficial for people with allergies or contact lens
solution sensitivities, and for those whose contacts tend to get
dirty easily. Their price may be a barrier for some. However, the
cost for this premium contact lens is equivalent to the cost of
a cup of coffee each day.
*ONE MONTH EXTENDED WEAR - these are a new type
of contact which are intended to be worn continuously without removing
them for thirty days. Then they are thrown away and a new pair is
worn for another thirty days before removing and disposing of them.
Sleeping with contact lenses overnight has shown to cause some health
issues in the past. However, these new lenses have supposedly addressed
these concerns because of their new advanced material.
*TORIC - these are contacts that include an
astigmatism correction. In the past, people with astigmatism could
not wear soft contact lenses. With today's technology, toric soft
contacts are becoming more popular. They are available in all types
of replacement schedules.
*BIFOCAL - the central portion of a bifocal
contact lens usually contains both the bifocal and the distance
prescriptions. This style of lens can be difficult for some people
to wear, but for some it allows them to not have to wear bifocal
glasses or reading glasses. They are available in all types of replacement
schedules.
*MONOVISION - this type of contact lens system
has proven to be an adequate alternative to bifocal contacts. It
involves fitting a regular contact in one eye for viewing distance
objects, and fitting a regular contact in the other eye for viewing
near objects. This set-up is easier to fit and significantly less
expensive than bifocal contacts. Any brand of contact lens can be
used with any type of replacment schedule. Some people find it difficult
to adapt to this monovision system.
TINTED CONTACTS
*VISIBILITY TINT - this is a very light tint
that makes it easier to see the contact lens when it is not on the
eye. The tint does not affect eye color and is included at no additional
cost.
*ENHANCING TINT - this is a transparent tint
that enables a person's own natural eye color to appear more pronounced.
It will not allow a person's eye color to appear a different color.
*OPAQUE TINT - this tint is unique in that it
will allow a wearer to change their eye color. These lenses require
a more exact fit and cost slightly more than transparent tints.
*COSTUME TINTS - the purpose of these
opaque tinted lenses is to give the wearer a very unique or "wild"
look by incorporating unusual designs in the contact. They are usually
worn only for special occasions.
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