Q:
For many years I’ve been using the Alcon “AirOptix Night & Day” plano contact lens (base curve 8.4, diameter 13.8) as my go to bandage lens after PRK, but I’ve noticed that some of these fit a little tight and some a little loose.
Enrique Corral suggested recently that exchanging the bandage lens on POD1 has helped his patients with pain, and I’ve started doing that as well, although my numbers are too small to say for sure if it helps.
In any case, I’m wondering if there is a better contact lens to use, or, should I alter my strategy so as to incorporate different base curves for different patients. If so, should we use the pre-op base curve to guide selection, or should we use the new calculated central base curve to guide our choice?
Perhaps I’m over-thinking this, but I welcome any suggestions.
Richard
Savannah, GA
A:
Perhaps I can contribute my experience with a “larger n”Based on my n=15,000 eyes of surface ablation, probably 1,000 PRK, 4,000 epiLASEK, 10,000 LASEK I’d recommend:
1. Don’t exchange the lens if it’s a proper fit as this just delays healing and may cause the new epi to come off
2. If you need to refit the lens routinely on POD 1 that probably means you’re fitting too tight
3. A loose fit is better than a tight fit, BC the latter causes hypoxia edema delayed healing and poor vision
4. Don’t stick the same lens in everyone. ODs who take pride/care in their CL fits would cringe at that one-base-curve-fits-all mindset<emoji_u1f609.png> Fit based on k. That’s postop calculated ave k, not preop k, as that would make little sense
At a minimum I’d recommend having 2 BCs for flat and steep postop ks. We used to use 4 different BCs but dropped to 2 wo any big decrement in ideal fit
You’re going to have to experiment with Ks and BCs because there are other variables involved (eg diameter, lens thickness and material, etc). So I can’t give you any rules about Ks and BCs
But trust me–once you do an analysis and try to optimize BCL fit post ASA by matching Ks with BCs, you’ll realize better comfort, faster healing, and better vision, which should be intuitive
Of course if someone’s doing 90% LASIK and only a few PRKs per year, it’s probably not worth going to this much effort, as less than 50% of surgeons are using BCLs post-LASIK anyway, and these are coming out so soon (1-2 days) that fit is almost irrelevant
Back when I was doing LASIK I started using BCLs postop, as it did seem to lower my incidence of epi ingrowth, with the BCL perhaps pushing the flap down, serving as a guide so the epi grows across not down, and a reminder for pts not to rub. I’m curious what % of LASIK surgeons out there use BCLs on primary cases (everyone does on enhancements for these same reasons, so if the logic holds there, shouldn’t it hold for primary cases, as well?)
Thanks and looking forward to seeing many of you at ASCRS—
Emil William Chynn, MD, FACS, MBA
Harvard/Columbia/Dartmouth/NYU/Emory-trained
1st eye surgeon in NY to get LASIK himself (1999)
Performed 5,000 LASIKs from 1996-2002
Switched to non-invasive LASEK in 2003
Have performed more LASEKs than any MD in US