How many drops a day are too much?

[calli66]

Dr G

I'm in that "severe dry eye" category, Schirmer ~2-3 mm. I have tried many soft lenses, and only Extreme H2O ("thin") works for me. I do use drops to re-wet my contacts--usually when I walk into a big store (grocery, home depot). I wear Panoptyx sometimes.

The lower water content lenses seem to be more uncomfortable for me. I have tried Focus N&D, Purevision, Optix O2, Acuvue Advance--I don't remember which ones were low or high. My eye doctor wants me to try Oasys, now that it comes in higher powers. ProClear lenses tended to "fold up" on my eyes when I blink---when I wore them outdoors. They seem very thin--they dried out. So lens design, thickness, rigidity, etc. all play into it.

In my previous post I mentioned that my New Mexico eyes doctors have always recommended higher water content lenses for dry eyes. Could you comment on that?

Whenever I try out a new lens brand, I wear it around the house on a limited basis first. When I go out anywhere, I ALWAYS take solution, lens case, and my glasses, in case I run into trouble and have to give up on contacts.

As I said in my original post--I really hold out hope for dry eyes/soft lens use, especially since companies are continually improving lens material/ design.

C66

[DrG]

Making blanket statements is always risky, simply because there are so many variables that cause dry eye, or the symptoms of dry eye in association with contact lens wear. The debate between low and high water lenses has been going on for decades. I had to do a presentation on contact lenses for dry eyes at a conference. This gave me the opportunity to research the entire bibliography. I also did a research project on my own where I measured the evaporation rates of different contact lenses on ceramic eyes under very controlled conditions. Out of all this I drew my conclusions about lens water content and dry eye performance. One of the materials I tested was the Extreme H2O material, which seemed to perform like similar materials with similar water content.

Having said that, surface characteristics of lenses interact with the tear film in different ways. Silicone hydrogel lenses attract lipids, whereas lenses like Proclear seem to be resistant to lipid deposits. I actually classify people on the basis of which type of lens they do better in, i.e. Proclear-tolerant dry eye patients, and silicone-hydrogel tolerant dry eye patients...one or the other, but usually not both. There really needs to be more research done in this area, and I wish I had the time to finish the study. Maybe somebody else will.

[20/20_Hindsight]

Did you use rewetting drops?

Yes. I put them in while in the car, walked into the vets office, sat in a chair for a few minutes and the lenses dried up to a crisp. I think I can wear them in my home environment where there are no fans blowing and I keep a humidifier blasting, plus I can administer drops when needed. Once I step outside my home, then everything changes. I wore Panoptx in the car on the way to the vets office, but removed them to go inside.

[YGB]

Thank you so much for the info. Dr. G.

Since my vision is good, do you ever try plano lenses to see if they help folks with certain types of dry eyes (i.e. silicon hydrogel or proclears)?

Interestingly, when my dry eyes were near their worse point a few months back, I did have a bandage lens put on my right eye due to a ridge that was causing irritation on my lid. I was surprised that my dry and very irritated eye tolerated the lens so well and in many respects (including dryness), it made my eye feel better. I am not sure what type of lens it was but I was instructed to clean it with Aquify (sp?). However, the lens was only used for 1 week since the MD thought that's all that would be needed to "heal" the ridge. It did seem to do it's job since the ridge problem seemed to go away after the week with the bandage lens.

[DrG]

A plano bandage lens? Certainly.

I have used bandage lenses successfully a few times with EBMD. In fact, I have used a bandage lens as a diagnostic test for EBMD-induced loss of visual acuity. As the lens bridges over the irregular epithelium, the visual acuity is improved.

[YGB]

Thanks again Dr. G.

Have you tried plano silicon hydrogel or proclears on dry eye patients to see if it would help them with their dry eye symptoms? I saw that you gave one example above but this patient seemed to tolerate her dry eye well prior to the contact lenses.

Also, in a previous post you referred to one of the lenses as the poor man's Boston Scleral lens (BSL). I am just thinking that it may be worth a try for folks to try a silicon hydrogel or proclear before taking the BSL plunge. However, I am still not clear as to whether these lenses may possibly be helpful to folks who have LASIK/other induced moderate to severe dry eye or are the lenses really for contact lens wearers who suffer from some milder form of dry eye. Many thanks for your informative responses.

[DrG]

Everything is decided on a case-by-case basis, and the ends need to justify the means. When a person suffers from severe dry-eye induced keratitis, and the vision is decreased, and/or there is severe discomfort then more heroic measures are justified.

I do think that a bandage silicone-hydrogel lens makes sense to try in applications where a scleral lens would be indicated, even if for no other reason than to give the patient a sense of hope that going through the time and expense of a scleral lens fitting will produce the desired results. Both treatments have risks, as does doing nothing.

[DrG]

Thanks again Dr. G.
Have you tried plano silicon hydrogel or proclears on dry eye patients to see if it would help them with their dry eye symptoms? I saw that you gave one example above but this patient seemed to tolerate her dry eye well prior to the contact lenses.

I see you already spoke about bandage contact lenses in treating corneal abrasions, where they are used to protect the delicate epithelium while it heals.

The one example I gave was one of the most severe cases of dry eye I have ever dealt with. Her cornea was one large fluorescein stain. Her vision had been reduced to 20/40, and she had photophobia. But, this had been going on for as long as I have known her. I don't think she "tolerated it well" as much as was resigned to it. Recently it has become worse, and she now has the luxury of time and the motivation to make it better.

The only other instance in which I would be compelled to try a bandage contact lens would be in EBMD, or epithelial basement membrane disease, and a rather severe case at that.

With respect to post-LASIK patients, the overwhelming majority of those are consulting me for vision issues related to severely elevated aberrations not necessarily related to dry eye. Only RGP lenses can help them because of the optics.

So, in my opinion, the major indication for bandage lenses is when there is significant disruption of epithelium, and not for the treatment of subclinical dry eye.

[Vicki In Oregon]

What is an example of a bandage silcione lens? I was told I have epithelial basement membrane disease in addition to dry eyes. I miss wearing my contacts but cant get comfortable just with my glasses, plugs, restasis, artificial tears, supplements that I dont know I would qualify for any other kind of contact that I could tolerate. The Oasis was so comfortable when I first put it on like all Accuvues have been for me, but it got soooo tight on my eyes after not too long..... Heading to Boston for their lens is a possiblity for me but the bottom of my list because of the risk of my not being able to wear a hard lens.

[DrG]

What is an example of a bandage silcione lens? I was told I have epithelial basement membrane disease in addition to dry eyes. I miss wearing my contacts but cant get comfortable just with my glasses, plugs, restasis, artificial tears, supplements that I dont know I would qualify for any other kind of contact that I could tolerate. The Oasis was so comfortable when I first put it on like all Accuvues have been for me, but it got soooo tight on my eyes after not too long..... Heading to Boston for their lens is a possiblity for me but the bottom of my list because of the risk of my not being able to wear a hard lens.

I agree that the Oasys may not be the best lens for you. It has a rather steep fit, and in a dry eye environment gets too tight.

The Focus N&D does fit a bit flatter in the 8.6 base curve. But you have to keep the lens hydrated.