Gas Permeable Contact Lenses
Guide
Gas permeable contact lenses, also referred
to as Rigid Gas Permeable, or Oxygen
Permeable lenses are the best hard contact
lenses available today. The use of silicone
in their structure allows gases,
especially health-giving oxygen, to pass
through the lenses and into the eye, almost
as if no contact lenses were being worn at
all. RGP contact lenses were developed in the
1980s, quickly becoming the best alternative
to previous rigid lenses. RGP lenses
actually allow more oxygen flow than soft
contact lenses. RGP lenses are also more
durable, and a good set of RGP contact
lenses could conceivably last for years.
Soft Vs. Gas Permeable
Lenses
RGP contact lenses are
stiffer than soft contact lenses, meaning
they retain their shape better than soft
contact lenses when you blink your eyes,
thus providing crisp vision for the wearer
more consistently. Vision correction
is especially superior for those with
astigmatism. This particular vision problem
is not easily corrected with soft lenses. They also are stronger
than soft contact lenses, so you will not
inadvertently tear them, which is a frequent
complaint of soft contact lens users.
Because they are not made with materials
that contain water, RGP lenses do not absorb
proteins and lipids from your tears; these
proteins and lipids are what frequently
degrade soft contact lenses.
The main reason people often choose soft
contact lenses over the RGPs is that they do
take some time getting used to them, whereas
soft lenses are usually comfortable right
away. This may be because soft lenses are
ultra thin and made of anywhere from 25% to
79% water. Soft lenses can also be made to
protect the eyes from UV light and the glare
that some people experience with hard
lenses.
RGP works better for
some eye conditions
Although many people use
soft contact lenses, there are certain
vision conditions that RGP contact lenses
are perfect for correcting. RGP lenses are
used to create scleral contact lenses, most
commonly used for treating keratoconus or
corneal injuries. RGPS are also ideally
suited for correcting astigmatism (as toric
contact lenses) and for treating children
who suffer from nearsightedness.
The one disadvantage of RGP
contact lenses is that they require much
more of an adjustment period than soft
contact lenses. They are not instantly
comfortable, and wearers may have to
re-adjust time once in awhile if they do not
use their RGP lenses for long amounts of
time. RGP contact lenses also require
frequent cleaning, although extended wear
RGP lenses are now being produced by some
manufacturers.
Bifocal prescriptions for those diagnosed
with presbyopia, can also come in gas
permeable lenses. The lenses allow for one
area of vision to be corrected for distance
vision and another for looking at things
close up.
Caring for Rigid Gas
Permeable Contacts
Caring for gas permeable lenses is the same
as for older types of hard contact lenses.
hey should also be stored in a saline
solution at night to keep them free from
deposits and ready to replace each morning.
Consumers need to weigh the costs of
cleaning and storage solutions over the cost
of replacing disposable lenses each month.
They often add up to about the same amount,
but with clearer vision and better eye
health in general possible with gas
permeable lenses, the choice is clear for
many people. So with the only real draw back
of gas permeable lenses being a short
adjustment period, they are a popular choice
among those of any age needing vision
correction.
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