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Modern contact lenses are safe and
effective for many patients when worn according to FDA
(Federal Drug Administration) guidelines. These
guidelines include approved wearing schedules and
recommended solutions for each lens brand and type. Our
clinic fits most types of contact lenses. Contact lenses
are made in both rigid (gas permeable) and soft
materials. There are lenses designed for nearsightedness
(myopia), farsightedness (hyperopia), astigmatism and
combinations thereof. Lenses are also being made for
those that need a bifocal type correction.
The most common contact lens
complication I see is the "Contact Lens Induced Red
Eye". Causes are generally:
1. Failure to replace contact lenses
according to the recommended wearing schedule. In
general a true disposable lens is replaced
daily with "one-day" lenses, weekly
with extended wear lenses ( up to
one month with Ciba's Night and Day lens) or every two
weeks if removed nightly. Frequent replacement
lenses are replaced every month or every two months
depending on brand and how fast a given patient deposits
tear protein on them.
2. Use of an unapproved solution or one
that a patient is allergic or sensitive to. There is a
difference in contact lens solutions. They are not
all alike. If you get burning or stinging when you
put your lenses on, you may need to try what I call a
"hypoallergenic" system. These are usually hydrogen
peroxide based systems and I recommend using
preservative free canned saline for rinsing prior to
insertion. Sometimes it takes your eyes up to 2 months
to heal from the effects of solution problems. This
would be without contact lens wear.
3. Sleeping with contact lenses that are
not designed for overnight wear (and thus not approved
by the FDA for such).
4. Tight contact lenses feel good
initially but as they compress or squash the blood
vessels at the edge of the cornea (clear front part of
the eye) the eye gets redder as the day goes on. I have
seen patients whose lenses were so tight that they left
an" impression ring" on the eye after they were
removed!
5. Tiny rips or deposits on contact
lenses can cause a red eye and may rough up the cornea
and allow bacteria to enter the cornea and cause an
infection.
6. Finally, eye dryness is a major cause
of red eye. Most of my patients live in Montana and it
is dry here. As we age, our tear quality and quantity
decreases. Eventually this dryness can cause patients to
just give up on their lenses. Sometimes switching
to lenses that you replace every day helps.
Some good news: There are some
new lenses have come on the market that have a surface
treatment that makes them much easier to wear in dry
country. I was wondering if the contact lens companies
would ever pay attention to this problem and they
finally have. This applies to both gas permeable and
soft lenses, including those for the correction of
astigmatism.
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CONTACT LENSES
