GPC, Dailies, Silicone and "Dry Eye"
There was a new comment on one of my old GPC posts that I want to address. If you read this blog and all of the comments you'll probably figure out a few of my biases, namely: 1) GPC is often mis-diagnosed. It is my opinion that VERY FEW contact lens wearers in their 20's & 30's have "dry eye". I don't know, I could be wrong here, but I hear and see docs all over telling these 25 year old contact lens wearers that their contact lens discomfort is from "dry eye". I just personally consider that doubtful. They switch a contact lens wearer from the old Acuvue 2's to a silicone lens like Air Optix Aqua, and a few months later (usually in the Spring...) the patient starts having comfort issues and the doc announces that it's "dry eye" and recommends artificial tears. I just want to say "really?". 2) I think GPC should be treated with Lotemax and dailies. Lotemax and dailies, Lotemax and dailies, Lotemax and dailies. I'm a broken record. I've said it hundreds of times and put it on my blog dozens of times. Not Tobradex, not FML, not Pred Forte, and certainly not tobramycin and gentamycin. I think sometimes even when these docs get the diagnosis CORRECT, they often fart around with 2 weeks of Tobradex and then let the patient go back to wearing their same old monthly silicone contact lens. I just don't get that. Hey at least they're not announcing it's "pink eye" and telling the patient to throw away all their makeup, so that's a start. But I see them blaming the solution and messing around with switching to different solutions. If it really is GPC, that won't work. You have to reduce the interaction between the stiff edge of the lens and the backside of the eyelid, and you do that by picking a "floppier" (lower modulus) lens, not by treating it as "dry eye" or changing the stuff you're storing them in...and dailies (plastic dailies, anyway) are the lowest modulus you can get right now. I think low-Dk lenses get a bad rap sometimes. The Dk would probably not be a problem if the patients wouldn't sleep in them. That's partially our fault (as a profession) b/c in the 80's we announced that "extended wear" was perfectly safe and the FDA approved Avuvues and the like for "extended wear", and once a lens gets approved for something, it's not getting "un-approved". Heck I think even the old polymacon and it's Dk of 9 or whatever is technically FDA approved for EW. Patients still argue with me that Acuvue 2 is safe for extended wear b/c it's FDA approved for it. Well...yeah, it is. Should it be? I mean I personally don't think so...not with our 2012 knowledge of corneal physiology. All of us OD's assume that patients are sleeping in them, and the studies confirm it. So we're all Rx'ing *mostly* silicone lenses b/c we think they're safer to sleep in. But one of the big problems is...silicone is stiff (high modulus). Some are stiffer than others, but they're all relatively (as compared to soft plastic lenses) stiff. Well stiff lenses cause GPC in patients who have seasonal ocular allergy. So the answer in GPC management is usually..."gotta get out of silicone". The new thing in our profession is silicone dailies. Maybe later I'll be on board with this, but I just don't see the point yet. No patient wearing daily disposable lenses is sleeping in them, or at least very few. So does a patient who is never going to sleep in their lens need SILICONE? I personally don't think so. And at least for me, the reason I'm usually Rx'ing dailies is to either manage or prevent GPC. So if I think the patient has "gotta get out of silicone", I am not going to Rx a SILICONE daily. It just seems counterproductive to me, maybe I'll change my mind later. If I have a 23 year old healthy contact lens wearer in the chair who is wearing silicone lenses and complaining of contact lens discomfort, GPC is way up there on my list of possibilities & probable diagnoses. "Dry eye" is not. Not to say that it "can't" be dry eye, I'm just not figuring that's very likely. I'm going to look at the backside of their eyelids and if they have bumps, I'm going with Lotemax and (plastic) dailies. I am not Rx'ing 2 weeks of Tobradex or announcing they have "dry eye" and switching contact lens solutions (while they continue to wear their monthly silicone lens). I know where I practice: a college town (Sam Houston State Universiry - EAT 'EM UP KATS!) in East Texas where the pollen, dust and mold are all at various times ridiculously high. It just seems way more likely to me for a SHSU student with contact lens discomfort to have GPC/allergic conjunctivitis than for them to have "dry eye".