"Ocular Discomfort Upon Tear Drying"

[neil0502]

Some guy's Master's thesis:

http://etd.uwaterloo.ca/etd/jpvariko2003.pdf

I've only skimmed it ever so briefly, but I think there's some valuable stuff in there, including chapters like "Corneal nerves - structure and functions--" something that affects me as well as some of you (post-LASIK types?).

This is quite likely to be what Foghorn Leghorn used to call a "long-haired book," but ... even a quick review of the Table of Contents might point you to something of interest.

The little bit that I read this morning speaks VOLUMES to my presumption about why I (in particular) am sooooo much better off wearing my contact lenses than wearing my glasses:

The cornea is one of the most sensitive tissues in the human body.

Take a concept, then, like "corneal HYPEResthesia" and ... we're talking about a fairly sensitive little cornea there.

Bon Chance!
Buena Suerte!
Mazel Tov!
Good luck!

[Flick]

Neil - I'm surprised to hear that your eyes feel better in contacts. Is that always the case or just for a few hours each day? Why do you think that is?

[neil0502]

Virtually always. I haven't found a circumstance under which contacts do NOT feel better than glasses.

There are several reasons that I know of, and probably others that I don't:

- It seems that the Benzalkonium Chloride damage--whatever else it did--left me with "corneal hyperesthesia," so my corneas are incredibly sensitive to ... everything. The contacts are a "bandage."

- I'm highly farsighted and quite susceptible to accommodative spasms. Contact lenses require less accommodation for hyperopes than do glasses. Glasses require less accommodation for myopes than do contact lenses;

- For whatever reason, I can "accept and tolerate" a "full cycloplegic Rx" in contact lenses (taking the maximum load off of my accommodation), but cannot accept all of it in glasses. This means glasses always force me to accommodate just a little, leading to fatigue, cramping, etc.

- Contacts give me access to wraparounds and Panoptx-type glasses. My eyeglass Rx is too strong to make in a wraparound.

Yeah. That about covers it

[Flick]

Interesting, thanks for sharing. Since I think contact lens caused my dry eye, I've stopped wearing them, but maybe someday I'll give them another try. I'm impressed that even with dry eyes and wearing contacts your eyes are not bloodshot.

[neil0502]

Welllll ... it's probably not right to say they aren't bloodshot. I guess I've just stopped paying attention. Fortunately or unfortunately, though, we went to a family get-together over the holiday weekend and a couple of relatives ... sort of set me straight.

Apparently, my eyes are fairly red--the right one more than the left, and both getting worse as the day goes on.

The Rigid Gas Perm trial that I went through (Intra-Limbals, made from Menicon-Z material (really high oxygen transmissibility)) failed miserably. The little plastic guys were -- as I called them -- Ragged Glass Particles on my newly-diagnosed "corneal hyperesthesia."

That said, though, my eyes haven't been as white in years as they were with those RGPs on, leading me to guess that MY particular breed of red comes more from inadequate oxygenation than the dryness per se.

But who knows...

[np1981]

Interesting, thanks for sharing. Since I think contact lens caused my dry eye, I've stopped wearing them, but maybe someday I'll give them another try. I'm impressed that even with dry eyes and wearing contacts your eyes are not bloodshot.

How exactly has contact lens caused you dry eye? Is it something to do with reduced corneal sensitivity? Several years ago I wore contacts (not for long) and couldn't find them comfortable, I'm wondering if I had very mild dry eye issues.

[kitty]

How contact lenses cause dry eye...

Contacts and Dry Eye

"As water evaporates from the front surface of the lens while being worn, it reacts by absorbing water from your natural tear film, causing you to have symptoms of Dry Eyes."

[np1981]

That seems to suggest that dry eye symptoms occur only when the contact lens are in place. But wouldn't that mean that once the contact lens is removed, the dry eye symptoms do not occur? I.e only having dry eyes during wear.