Re: Extreme H2O contact lenses for dry eyes

This issue of contact lens comfort and dry eye comes up often in this
group. I'd like to add a few comments.

1. the water content of the lens has little or nothing to do with the
lens surface losing moisture and becoming uncomfortable. That is a
general statement and does not apply to ALL soft lens plastics but is
generally valid. It is true, however, that some lower water content
lenses maintain hydration better than higher water content lenses but
the reverse is also true.

2. for some people, the actual cause of apparent dryness issues is a
problem with the contact lens care products---multipurpose solutions
(USA brands like Opti-Free (three formulations), RenNu (four
formulations in the last two years), and a few others) being the most
likely culprit. It turns out that brand A might be fine to use with one
plastic and not at all appropriate for another plastic. And once in a
while the chemicals in the storage solution just don't agree with a
wearer's eye tissues. There's also an issue with "discount" and "store
brand" multipurpose solutions. What's in the bottle you bought last
month might not be the same formulation that's in bottle you purchased
yesterday. The fix for this issue is often switching to a hydrogen
peroxide based storage solution such as ClearCare, AOSept or Ultracare.
These are USA brand names. The brand names in other countries are a
little different.

3. there are three specific materials that tend to perform better for
people with dry-er eyes: higher water materials omafilcon (Proclear
brand), hioxifilcon (Extreme H2O and more than a half dozen other
brands) and lower water content materialsilicone hydrogels (Oasys,
Optix, Purevision, Night&Day brands.)

4 and then sometimes is doesn't matter what you do--- it's a real dry
eye problem and the fix has to be treating the underlying cause of the
dry eye. That's a whole other discussion!

LB, O.D.
.

Relevant Pages

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    (rec.photo.digital.slr-systems)
  • Re: Big Eye Ball
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