Episode 2: Nicholas J. Bruns, OD, FAAO, and John A. Vukich, MD, of Summit Eye Care of Wisconsin, discuss the growing number of tools clinicians have to treat dry eye, and the role of neuromodulating eye drops.
What follows is a lightly edited transcript of the conversation
Nicholas Bruns, OD, FAAO: Thanks for joining us, everybody, tonight. My name is Nick Bruns. I am joined by my awesome friend, colleague, partner in crime at Summit Eye Care in Wisconsin, Dr. John Vukich. And we're going to talk about a topic that's just super hot right now, especially in surgical eye care. And that's ocular surface optimization, dry eye, the whole subcategory of dry eye.
John Vukich, MD: Thank you. This really is an important topic. The prevalence of dry eye just continues to grow, and the importance of it in optimizing visual acuities is so important. We’re realizing that now as we get into the premium channel implants, knowing that really the rate-limiting factor, we used to think of the macula as the only place where we had to worry about what we could achieve. Now it turns out that the ocular surface is an important limiting factor for many patients and one that we can actually make improvements on.
Dr. Bruns: Especially when we get down to the premium lenses that we've got, multifocals, EDOF lenses, adjustable lenses. I mean, it's no longer macular potential. It is really ocular surface potential. And we have so many tools in the toolbox. Can you talk to me a little bit as the surgeon, how does a pristine ocular surface affect the adjustments? How does it affect the measurements when we're going into a premium surgery? How do you talk about patients to that, about the importance of that?
Dr. Vukich: Even before I discuss it with patients, I take a look at the topography. When we talk about the K values, that is a one-to-one correspondence to the intraocular lens prediction. So if you have a keratometry value that is smoky or is certainly not as clear as it could be because of dry eye, you can lose a half a diopter or more in certain circumstances just on the calculation accuracy, not even to mention the degree of astigmatism and the axis of the astigmatism. So, just right off the bat, in order to get optimized results, we have to have an optimized tear film.
Dr. Bruns: Yeah. I mean, especially degrees of astigmatism. I like that you mentioned that there because we are able to correct now with lasers in our low-level torics certain degrees of astigmatism and very low levels of astigmatism. But somebody who's got ocular surface degree, it can be ocular surface disease, it can be very difficult to identify the axis appropriately. And you could be off by as much as 10 to 15 degrees, and that can be the make or break between a good outcome and a just average outcome.
Dr. Vukich, MD: Yeah, absolutely. We talk about what is the prevalence of dry eye--there was a Department of Defense analysis, almost 10 million patients that were looked at with a questionnaire between 2003 and 2015, and the prevalence of signs with symptoms raised 3 times. It went from 0.8% to 3% overall. It's a huge increase. And if you looked at just symptoms, and most of us understand that often dry eye, you can't really see it when you look at it, but the patient complains about it, it's up to 40% of patients will complain that they have dry eyes, even though you may not see SPK or other physical findings. So, it's really important to understand how do we make our patients happy. And the ocular surface is just an obvious place that we can work and modulate and make better.
Dr. Bruns: Now, why do you think that is? Why do you think that prevalence has gone up so much? Are we just looking for it more, we're identifying it faster, or is there something that's changing in the environment?
Dr. Vukich: Well, I think what's happened is that the prevalence has really shifted from what was believed to be aqueous deficiency to probably more evaporative, that we're just simply losing our tear film to evaporation. And some of that may be near-acuities tasks. I mean, how many of us spend hours a day on our tablet or cell phone? And that is also reflected in the fact that younger patients are getting dry eyes. And there's a lot of thought that maybe this is just related to screen time.
Dr. Bruns: I think you're totally right. I mean, literally what we're doing right now, I'm staring at a screen talking to you. I've got my phone sitting within arm's reach here. I've got another screen right here. And as I'm sitting here talking to you, I'm reminding myself, "Hey man, blink. I got to blink." So, I think that's a big part of it. I think it's a huge part of it, is just the environment. I think we have also become better at identifying it. We've got fancy tools now in the clinic, but you don't have to have the fancy tools in clinic to really be able to identify and manage dry eye. I mean, the simplest thing you can do is just a little bit of stain. I mean, when I have a patient coming in and specifically for a surgical eval, I will always put in some fluorescein and just have them blink. You just have them blink real quick and you look at, well, number one, is there staining happening? And then number two, what's that tear breakup time? It should be close to 8 to 10 seconds in a normal healthy eye. But a lot of our patients, especially our pre-op patients, it's closer to 1, 2 or instantaneous tear breakup. So, we look at how do we manage this?
I mean, we have this massive toolbox now. As recent as 15 years ago, we had basically one medication. It was cyclosporine. And we had a multitude of different types of over-the-counter therapies and hot compresses and what have you. But fast-forward to today, we've got not only immunomodulators, we've also got our tear film stabilizers, we've got neuromodulators, we've got human growth factor medications, too, that all kind of roll into this big huge category of ocular surface disease, which not only, like you mentioned, is aqueous deficient, but it's also tear stability deficient. And then also kind of rolls into neurotrophic keratitis where the cornea just is so damaged that it can't even feel that it's damaged, so it can't produce these tears. So, we've got all of these different things that really are at our disposal, which it's incredible to be a part of eye care as it continues to evolve. And we have all this amazing stuff at our disposal.
Dr. Vukich: So, really, what it means is not only can we modulate how the tears evaporate, and there are anti-evaporative medications, and perfluorohexyloctane, is one that's really grown in popularity, but that's just part of the story. Anti-inflammatories, cyclosporine formulations, as you mentioned, those were available early on, and they have the best efficacy for signs as opposed to symptoms. So, a lot of times when patients have SPK, the cyclosporines work well, but how do we handle the patients who have aqueous deficiency?
Well, now we have neuromodulation drops, which are really important. The TRPM8 drops that have just now been available and made available in the United States actually increase not only tear production, but they increase mucin and they increase meibomian gland secretion. So you've got the entire package of what supports tear function and ocular surface. So, we have several different ways, and part of it now comes back to us as providers and like, "Okay, so what's going to provide the best possible outcome for the patient?" And so, we now have better choices, but we also have to make a better diagnosis as to where to start and what to do.
Dr. Bruns: Yeah. When I talk to patients about dry eye, different medications, too, it's not one size fits all. If I had a magic pill to give you, I would give it to you and it would fix everybody, but we don't have that. So you have to identify what's going to work best for that patient. Is it inflammatory, in which case an immunomodulator would work well, or is it a tear film stability issue? Or, like you mentioned, the neuromodulators, that whole new category of drop kind of works above and further upstream. We've got this cycle of, I like to think of it as a cycle of death, the cycle of death on our ocular surface, where you have tear film instability that leads to cell death, which leads to tear evaporation, more inflammation, and it just goes around and around in a circle. If you can stop upstream... And that's what neuromodulators do. They stop upstream, so you don't get into that cycle, and they tend to work very, very fast.
So, yeah, I think you're definitely right. It kind of comes down to how do we identify what this patient is really needing and what's the best fit for them? But when we look at it from a surgical standpoint, we also want things that work fast. When a patient decides that they want a several-thousand-dollar premium elective surgery, they want it now. When we have to tell them, " Let's maybe pause briefly and try to optimize your ocular surface," sometimes that can be a little bit difficult for patients to understand. But the way I frame it is, "Hey, you want a premium outcome. You got to put in a little bit of work. And there's some work before surgery, there's some work after surgery. So we are together to try to really elevate your outcome, which you're paying for." So, it's really cool to be a part of this, and all of the different medications and options we have are just, it's phenomenal.
Dr. Vukich:, I think one of the important things that we should touch on before we close is that when do we move from an over-the-counter medication, over-the-counter drop, tear drops, because many of our patients, if not the majority, they're self-medicating. And so, what triggers the need to say, "All right, now we're going to move you into a prescriptive medication."
Dr. Bruns: That's a really good point. It's kind of like if you go to your dentist and you've got a toothache and you've been using Crest for forever and your dentist, what if they just told you, "Well, why don't you switch from Crest to Colgate?" You might look with a kind of puzzled look at your dentist and be like, "Really, that's it? That's your solution?" That's like going from one artificial tear to another. So, I think artificial tears are fantastic, and I think patients do self-medicate as long as they're using a good brand. I like preservative-free ones, lipid-based most of the time. If they're already trying that on their own, and most of the time they present to you already have tried that, that's your cue and your job and your role as the physician to elevate to the next level. And the next level is usually a prescription or some sort of in-office therapy. So, I think that really is a pretty easy solution for when to take that next step.
Dr. Bruns: Thank you so much. It was great chatting. And, thanks, everybody.
Dr. Vukich: Thank you.
