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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.
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
