Ophthalmology off the Grid
What's Next for LASIK?
Gary Wörtz, MD, invites three surgeons to share their perspectives on the evolution of LASIK technology. Asim Piracha, MD, remarks on how far LASIK has advanced since 1999 when he first performed the surgery. Bill Wiley, MD, discusses his experience with topography- and wavefront-guided LASIK, and Karl Stonecipher, MD, shares the outcomes he has seen with Contoura Vision.
Gary Wörtz, MD, invites three surgeons to share their perspectives on the evolution of LASIK technology. Asim Piracha, MD, remarks on how far LASIK has advanced since 1999 when he first performed the surgery. Bill Wiley, MD, discusses his experience with topography- and wavefront-guided LASIK, and Karl Stonecipher, MD, shares the outcomes he has seen with Contoura Vision.
Gary Wörtz, MD: Open. Outspoken. It's Ophthalmology off the Grid, an honest look at controversial topics in the field. I'm Gary Wörtz.
LASIK is a procedure that has been around for over 20 years. It has evolved and grown over time and, most recently, with the introduction of topography-guided treatments. I wanted to talk to some of the best surgeons in the field to get their perspectives on the advances of LASIK. Where are we going? What works best for them?
First, I sit down with a mentor of mine who I met when I was still in med school, Dr. Asim Piracha. He shares his take on the evolution of this technology.
Asim Piracha, MD:
The results are really quite amazing, and I always wonder what's holding it back?
Gary: Next, I speak with Dr. Bill Wiley to find out topo-guided LASIK has allowed him to expand treatments to patients that he did not consider candidates in the past.
William Wiley, MD: We've all, over the past probably 5 or 10 years, have seen patients with irregular corneas and said, "Well, there's technology that's coming. Why don't you wait for that technology to come out?" Finally, we have this technology, and those patients have started to trickle back in.
Gary: Finally, I sit down with Dr. Karl Stonecipher to hear his perspectives on the Alcon roll-out of Contoura Vision and get some great pearls for those who are new to this technology.
Karl Stonecipher, MD: I started working with this obviously in the FDA trials, and we got some of the best results we've ever seen with uncorrected visual distance visual acuity. On top of that, we've gotten some of the best results in terms of reducing glare, reducing halo, you know, some of these side effects that are unwanted.
Gary: Listen in. It's going to be a great episode.
Speaker 5: This episode of Ophthalmology off the Grid is supported by Centurion, by Alcon.
Gary: This is Ophthalmology off the Grid with Dr. Gary Wörtz, and today I have with me a friend and mentor, Dr. Asim Piracha from Louisville, Kentucky. Asim, I just want to say thank you so much for not only taking time to talk to me about your experience with LASIK and sort of the great LASIK debate that's going on right now. A lot of people don't know this, but you were actually a real big reason why I became an ophthalmologist. Just to kind of go back, you were the guy, when I was a med student, I came over and shadowed and got to see cataract surgery, got to see some LASIK. That played a pretty big role in me following in your footsteps at UK, so it's just kind of funny now, years later, getting to look back on that experience. I'm really super thankful for all you did then and continue to do for me as really a mentor and friend. With that being said, I just want to say thanks for spending some time with me today and giving us and the world at large some of your insights in terms of what's going on with LASIK right now.
Asim: Well, you're welcome Gary, and thanks for including me! Actually I'm very excited about doing this with you. I think it's a great topic, and actually I do remember that day very clearly when you came in and you were in med school and didn't really know what you wanted to do. We spent some time in the OR and I could just see your eyes light up. It almost, that day, looks like you decided that's what you wanted to be.
Gary: Yeah! Yeah.
Asim: That was pretty cool.
Gary: Yeah, it was really a pivotal moment for me, so it's really, really cool that we got to share that.
As you know, we've gone through a renaissance with LASIK from the very beginning, starting with broad beam lasers and PRK and going into more advanced lasers for LASIK and going from broad beam to flying spot and, you know, from a conventional platform into the more the wavefront-guided treatments. Now, we're trying to catch up with the rest of the world who's been doing topographic-guided treatments, and we have two platforms that are approved. One is the WaveLight Allegretto platform, which is approved but essentially not being widely used at this point, not been widely released.
As you look at where LASIK has come from and where we are now, and perhaps where we're going, where do you see the landscape right now perhaps evolving or do you feel like where we are right now is a pretty hard place to improve upon? I'd just love to have kind of an overall overview of what your thoughts are on the current state of the technology.
Asim: Well, I think LASIK has evolved actually a lot just in my career. I started doing LASIK in '99, and we started off with the ACS and Hansatome microkeratome and used other ones as well. Then we went to the standard treatments, then to the custom treatments. Really where it is now is, I do think the platforms are mature. I mean, the femtosecond lasers to create really nice flaps, safe flaps, uniform planar flaps has really reduced the risk of ectasia. We get nice, well-centered flaps over the visual access and pupil, so the whole ablation is fully within the exposed bed. Then with the current lasers, either the Allegretto system which I use or the VISX CustomVue and now the iDesign is coming out, the Nidek options I don't have experience with but the results are really quite amazing. I always wonder, what's holding it back? Because, if you look at the data, the data is remarkable. I mean, excellent high 20/20 outcomes, low enhancement rates, good quality of vision, very few enhancements in our practice, and very few complaints. It's really evolved.
I think the issue is some of the perception of the public at large, maybe myths, maybe some unrealistic fears or unfounded fears from prior generations of LASIK. Right now it's quite mature, but we can always get better. We can have faster lasers. We can have great ray tracing technology. We can have better alignment on the visual axis, compensate for angle kappa. So a lot of things can be done still, but right now it's mature, and I think it will continue to evolve.
Gary: You know, that's a great way to say it. The technology is very mature. One thing I tell friends or potential patients is, the newest news about LASIK is that it's old. LASIK has been around since the mid- to late-90s, and we are essentially using the nuts and bolts. Obviously as we've mentioned, things have improved, but the basic procedure has really been around for quite awhile now—going on 20 years. We would really know if this was not a technique or not a procedure that had legs and that was not going to be good long term, I think, at this point. Your point is well made that this is a mature technology.
Sometimes we're getting so close to perfection, anything you change it's sort of like standing at the North Pole. Any step you take, you're going south. Where we are, not to say that things can't get better, but it is really going to be difficult to take a platform, especially like the WaveLight Allegretto, with the wavefront-optimized treatment, that you know is very robust. It seems to be very well tolerated, lots of happy patients. It's really tough to trade that in for something that may potentially, at least going through a learning curve or have other issues, in the short-term may not give quite as good results.
That's where I feel like there is a room for debate right now, as to do we take this next step into the topo-guided treatments? Where I would see this working, and as we have discussed also is, especially in those corneas that maybe had a decentered ablation in the past, or maybe they're an aberrated cornea for one reason or another, or maybe a corneal transplant, or just a patient that doesn't have a normal topography for other reasons. This could give them a chance to normalize their topography and give them a chance at good vision, whereas a traditional treatment would not do that.
What are your thoughts on that?
Asim: Right, so I think that's the irony here. I think that wavefront-optimized is, you know, it's a pure refractive treatment. Meaning, it corrects a refractive error, and it does not induce additional higher-order aberrations, which mainly is spherical aberrations. We get great quality of vision and great outcomes with the wavefront-optimized, and it's very consistent. You do a refraction, you see if the patient can see with that, and there's very little artifacts or noise in the system.
If you throw in the topographic-guided treatments, I think what you're saying is correct. It can be used for a select few patients who have irregularities, like wanting to enlarge the optical zone or have some early signs of keratoconus, and you want to normalize and make the cornea more regular. But the approval for the T-CAT, or topographic-guided treatments, in the United States is actually on virgin eyes. It should be on patients that have very little irregularities of the cornea, and their topography needs to match very closely with the refraction. It's only proved for LASIK, so the approval for topographic-guided are not the patients who would benefit the most from topographic-guided and actually have more risk for getting some outliers if not done perfectly well and not a very astute clinician and surgeon who can really look at the measurements, make sure the measurements are perfect, make sure they're accurate, and make sure they're consistent. Or else you could get some unusual outcomes.
The ideal patient would be, let's say a forme fruste keratoconic patient, or a patient with a previous LASIK with a decentered ablation or a central island or a small OZ. In that case, you do a surface ablation, you know, PRK or ASA, whatever you call it, combined with maybe cross-linking. But that's not what we're using it for in the United States when it gets released to the general public.
Gary: Well, and I think all of that is really where we're all sort of scratching our heads right now. The release to the masses, if you will, with the WaveLight has sort of been, I don't want to say delayed, but I guess it's been slower than a lot of people have thought it would be. I think that has to do with the fact that there's perhaps a lot of ways that you could introduce noise, or introduce errors, if you're not careful.
Asim: Right. That's actually to Alcon's credit. This was approved a couple years ago. It's only being released now, probably this spring, but it's been approved for a couple years, I think since 2013. And so, the reason why it's been delayed is that the, several well-intentioned ophthalmologists, LASIK surgeons, warned Alcon that, look, this is a very powerful tool, but you can't just release it and have everybody start using it because you'll get some problems. I think they've been cautious, and I give them credit for that. I think that everybody is going to go through some 4-hour course to learn how to use it, and they're going to be selective in rolling it out. That's to their credit. But the reason is because, right, if you don't know this technology inside and out and you don't plan each patient very meticulously, you could get some unusual outcomes.
Gary: Well, and I agree with you. You know, the last thing any company wants to do is release their product before it's ready for prime time, and it is to their credit for being cautious. I will give them a lot of credit for doing that, because it's very tempting if you're a company and you're looking for sort of the next flashy thing to get it rolled out. But I agree with you that an abundance of caution is warranted whenever you're talking about changing something that is so successful, so well-established. It's a difficult thing they have set out to do, to improve upon something that is, gosh, very, very close to perfection in terms of the wavefront-optimized.
Asim: Right. I mean, the other thing, just as a kind of a perspective, is that this technology has been around for about 12 years, maybe 13 years, internationally. It's been approved here for a couple years, and we're just getting it now. If you look at the actual patterns of use around the world, people have had all of them available. You know, wavefront-guided, wavefront-optimized, and topography-guided. The topography-guided treatments are still a very small percentage, maybe 2% or 3% in a very advanced clinic, like David Lin's clinic in Vancouver. He's been talking about topographic-guided treatments for forever, and he had that four-step TNT pattern he talked about. But even in his practice, where he gets a lot of unusual patients and a lot of patients that have previous issues, he's only using it 2% or 3% of his patients. The rest are not getting topographic-guided, so I think we have to use the experience of our international colleagues and make sure we're not stepping into an area where we're going to regret in the future.
Gary: Well, and that goes back to your earlier point that you made about irregular corneas potentially forme fruste keratoconus patients, patients who've had decentered ablations. To me, if I'm looking at the big picture, I would love to have topographic-guided treatments for patients who have those issues and I can do cross-linking at the same time. You know, it really seems like maybe the missing piece of this all at this point may be the access to corneal cross-linking, because a lot of people in this area have been sent up to Ontario, you know, in the Kentucky area, have been sent up to Ontario for surface ablation, you know, topographic-guided surface ablation and cross-linking just because we don't have access to those technologies. If you're looking at the big picture, I think that that may be the niche that you're really looking at to say, "This is the group of patients that we could really sink our teeth into justifying a topographic-guided treatment."
What are your thoughts on that as maybe the missing piece, or the missing partner, to topographic-guided treatments?
Asim: Right, I mean, I think that's the perfect partnership or perfect combo is topographic surface ablation with cross-linking to fix irregular corneas. It's nice to have that ability, so to have that as an option in our toolbox, to offer wavefront-optimized, wavefront-guided, topographic-guided, and select the patients out perfectly. It's nice to have that, and I want it, especially for patients who have some irregular corneas. But I will, at this point, look to be cautious on who I use topographic-guided on because of the issues we talked about. What's interesting is, the 20/20 outcomes are highest with wavefront-optimized, but the 20/12.5 visual outcomes are highest with topographic-guided. There is potential for improving beyond what we can get with WaveFront Optimized, but on the other hand there are more outliers. The question is, do you want to aim for that 20/12.5 with a little bit more chance of having some unusual outcomes, or do you want to aim for the 20/20 outcome and have very few, if any, unusual outcomes?
Gary: Yeah. Hopefully we don't have to make that choice. Hopefully we get to the point where we can have our cake and eat it, too. But everything at this point, there are trade-offs where we're trying to chase perfection, for sure.
Asim, I just want to say thank you so much for weighing in on this! I share a lot of your perspectives, your concerns, and also the hopes for this technology really finding its own place. I really appreciate you coming on and giving your insights.
Asim: Thanks for having me, and I do feel that LASIK has a great future for our patients. It's an amazing technology, an amazing procedure, and it will continue to provide excellent outcomes.
Gary: This is Dr. Gary Wörtz with Ophthalmology off the Grid, and once again we have with us Dr. Bill Wiley from Cleveland. Bill, just want to say thanks for taking a little bit of time out of your evening and talking to me and the rest of the audience about topography-guided LASIK. This is really the LASIK debate. We're going to talk about topography guided LASIK versus wavefront-guided LASIK, and then obviously wavefront-optimized or more or less traditional LASIK.
With that being said, Bill, thanks for taking some time out tonight.
Bill: Sure, thanks Gary. Thanks for having me. This is a great subject, and it's definitely, now that we have different options, it's good to discuss what do those options mean as far as for us for refractive surgery.
Gary: Yeah, absolutely. You know, I think we both do a fair amount of LASIK, and sometimes it's you figure out your patterns, you figure out what works in your hands and works with your technology in your clinic, and sometimes, especially in LASIK, when you get such great results in general, it can be a little bit difficult to think about changing your practice pattern because it follows that old adage of “if it's not broken, don't fix it.” But you're one who likes to always be on the cutting edge. Again, you're someone who I look to when I'm thinking about maybe investing in new technology or new ideas, I always like to kind of get your opinion on things.
Walk me through your process of going from a procedure that is working great and working well for your patients, maybe even with technology that's paid off. What made you want to make the switch to topography-guided LASIK? Then maybe we'll ask some other questions about your experience.
Bill: Sure! Sure thing. You know, I think a lot of it has to do with, it's just a matter of percentages and getting a larger patient base with a better percentage of 20/20 or better than 20/20. I think traditional LASIK worked quite well. 10 years ago, all we had was the Nidek laser. In general, most of our patients did well, but we saw that some of the higher prescriptions or some of the larger pupil patients or some of the high astigmatism, the rate of 20/20 wasn't satisfactory. I look back at my old results with our old Nidek, and, in general, we are about 60% to 70% 20/20 or better across all patients, which, at the time, was pretty good. But what happened was, over time, patients expectations rise. You want to be able to treat every patient as best you can and have that high chance of achieving their expectations.
I think the newer technology, a lot of times, captures some of the outliers or just raises your overall chance of getting that right prescription across the board. Early we went from Nidek to wavefront-guided treatment with the Visx, and we noticed an increased opportunity of achieving that 20/20 goal. I think what it allowed to do, it allowed the Visx to treat a little bit wider zones allowing for a little bit more stable prescription. In general, you know, we still use that same Visx wavefront-guided treatment.
Around those times we also adapted the wavefront-optimized platform, the Allegretto laser, and we saw that that was getting great results and very similar results to what we're seeing with wavefront-guided. We had this wavefront-optimized versus wavefront-guided, and I think there was a lot of back and forth which platform was better, or which technology was better. I think in some patients we saw them better with wavefront-guided and some did wavefront-optimized, so we ended up offering both platforms and I would just try to choose which patient group seemed to fit better. It seemed like the higher prescriptions seemed to do better, where with the wavefront-optimized, a lot of it may have to do with the speed of the laser treatments and less drying times.
Also, sometimes some of the higher order aberrations could affect your overall treatment and you might have treated higher order aberrations but overall missed the spherical equivalent. Sometimes wavefront-optimized allows you to hit that target with maybe a little bit more precision if it's a relatively normal eye. That brought us up to about a year or 2 ago, offering both wavefront-guided and wavefront-optimized platforms. Then about a year or two ago we integrated Nidek topo-guided treatments. What we saw was that it again raised the level of satisfaction and percent of 20/20's, so with the newest platform we're over 95% 20/20 which is pretty amazing. Looking back over 10 years with our original Nidek, we're about 60% 20/20, so we've really increased the opportunity to hit that target and now we're starting to measure 20/15 and we're about 60% 20/15, so our sort of 20/15 level is where our 20/20 level was back in the day.
We still offer the other platforms, wavefront-optimized and wavefront-guided, but I found that some of the advantages I think to topography-guided, what I like about it, there's a few different things that make it stick out. Number one, you're treating the manifest refraction, at least with the Nidek platform it allows us to treat the manifest refraction. Sometimes with wavefront-guided, you're sort of taking a leap of faith that that machine has captured the correct spherical equivalent and the correct refraction. With topography-guided, you're taking the manifest refraction and then adding on top of that the irregularity of the topography. You have this trust in your in-the-chair refraction that's going to be translated to that patient, so I think that's an advantage. Also, you get to study that topography and see what the preoperative topography looks like and the postoperative topography, and see, does it make sense? Is it treating that eye the way you liked it, what you'd expect it to do, and you see what the topography is going to be, what it's predicting is, I guess, is the final topography.
Sometimes you may be in between the exact axis. Maybe you've done a few different refractions and they're psychoplegic, or let's just say axis 90, and their manifest was axis 95. You get to see, you can plug both of those treatments into the topography nomogram and see, what does that do to the topography and does it leave the end result with what you're expecting? I think having that opportunity, to see what the eye's going to look like after the treatment, can help sort of raise the overall outcome level with that topography guidance.
Gary: Well, you bring up a lot of really interesting points. First of all, just the progression of laser technology, and with the progression of laser technology the increased patient expectations. It's sort of the chicken or the egg, you know? As technology gets better, patient expectations get higher, and that requires technology to get better. It's sort of this back and forth, and sometimes you think about patient expectations as a bad thing but actually, as we've been discussing this, I sort of think as patients expect more we expect more out of ourselves. That really does drive technology to get better as well, so maybe in some ways patient expectations and expectations of ourselves really does help drive technology to the next level.
To drill down on a couple of the points you made. Wavefront-optimized, or traditional LASIK, there's something about it that's just so simple. You have a refraction, and you plug that in and it really is a what-you-see-is-what-you-get kind of result. As long as someone is seeing pretty well through the phoropter, you know they're going to do pretty well with their LASIK treatment.
With wavefront-guided treatments, like you mentioned, there's a leap of faith. Not only is there a leap of faith, but a lot of that is dependent on the pupil, and what is their pupil size when you measure their wavefront refraction? We kind of have this 75/50/15 rule where the sphere has to be within 0.75 D, the cylinder has to be within 0.50 D, and the axis has to be within 15 degrees of our manifest refraction to really feel like we can trust the wavefront refraction. But still, that's a little bit … in this day and age, that's a little bit of variability that we don't really like, and so we kind of all have this leap of faith, as you mentioned. As obsessive compulsive surgeons, we don't really like that, so I can really wrap my arms around how maybe topography guided treatments, it may be the best of both worlds it seems. Where you're still trusting your 'in the chair refraction', but having a real handle on topography through years of experience, not only made with cataract surgery but also with LASIK and looking at a lot of topographies, it may be that that really just makes more sense.
Because even, as I have come to understand, wavefront aberrometry, it still is a little bit of a conceptual leap to really feel like I fully understand all the ins and outs of higher-order aberrations, whereas I know what a good topography looks like. It sounds like, with your ability to plug in the treatments and look at the topography and then look at what the postop topography is going to look like, you really may have a better overall gestalt of what the patient is going to be doing afterwards. Maybe that's where you're able to provide better results for your patients, because you're combining the science and the art of medicine. Do you feel that's possibly a fair application?
Bill: Yeah. That's a great way to put it. There's the science and the art, and I think, at least in the US with the wavefront-guided, it relies more on science maybe a little bit less on are you restricted to be able to make those adjustments and that leap of faith can be a little bit anxiety-provoking. Like you said, there's a wide range there of what's considered normal, but if you can get a great in-the-chair refraction and treat it like it's a subjective number rather than an objective measurement that may or may not fit what the patients looking to see. A lot of the times, an objective honor refraction may not fit the subjective, in-the-chair refraction. A lot of times, we don't prescribe glasses or contacts off of objective measurements. Typically we're going off of subjective measurement, and I think that's where the art comes in.
So far, the topography-guided platform allows you to mix both of those techniques. I think that's a great way to put it, you're mixing the art and the science. It gives the surgeon sort of that ability to make adjustments as he sees fit.
Even something simple as, let's say monovision. Currently, with the Nidek platform, I can plug in any refraction so I can scale back the one eye for near vision and feel confident we're going to hit that with the current gates that we have for wavefront-guided. We just don't have that ability to type in a different refraction that's outside of the 0.75 adjustment.
Gary: Bill, let's talk about what I think is on a lot of peoples minds, which is what about those corneas that maybe are irregular? Maybe patients who have had a decentered ablation or maybe an irregular cornea. I'm not going keratoconus patients or forme fruste keratoconus, but maybe patients who are just, have a little bit more irregular astigmatism. That's where, I think, a lot of people feel like topography-guided is really going to allow us to have a new tool to treat corneas that maybe in the past just wouldn't be good LASIK candidates for a lot of reasons.
Have you wandered into the weeds with patients who maybe have had previous treatments and needed to have an enhancement to normalize their topography or some other example of a case perhaps that topography-guided treatments have allowed you to do something that perhaps you couldn't have done in the past?
Bill: Yeah. That's a great topic, and I think that we can dive back in to sort of the application as far as, is it best for normal eyes or should it only be used for irregular eyes? There's two different schools of thought, but let's first discuss sort of the abnormal eyes.
I have had the opportunity. We've all, in sort of the past 5 or 10 years, have seen patients with irregular corneas and said, "Well, there's technology that's coming. Why don't you wait for that technology to come out?" Finally, you know, we have this technology and those patients have started to trickle back in. They've said, "Hey doc, I see that topography-guided LASIK got approved. Can I be treated now?" It's sort of put a little bit of pressure on us because I've kind of been pushing these patients off and off and waiting, and now they're finally coming home to roost and say, "Hey, now I want that treatment."
A couple examples would be, let's say, a decentered ablation. With an older technology, let's say, we've had a few patients that had treatments prior to eye tracking and there was some decentered ablations. Those patients have been waiting for quite some time, and we have had the opportunity to treat them with topography-guided LASIK. The results, so far, have been fantastic with it. The patients I've treated with these irregular corneas have all done very, very well. A couple decentered ablations, a couple sort of irregular, sort of forme fruste keratoconus-type appearance where they've had, let's say, cross-linking to stiffen their cornea. Now we can do a small treatment to make their irregular corneas more regular.
I've treated one patient that had a history of corneal transplant that had an irregular cornea after corneal transplant. All those patients have done quite well. I think we do have to be careful as far as what we're promising, again, but as far as setting those expectations. Now, like you discussed earlier, is sort of that expectation/technology curve. Now we do have better technology, but we have to be careful. Still keep that expectation in check, that I tend, especially these early patients, I haven't promised too much. I said, "This may take more than one treatment. Our hopes are to make it better, but it may not be perfect." So far, the patients have been happy, but I'm looking forward to sort of treating this more widely. So far we've only treated a few other highly irregular corneas, and we're starting to become more comfortable having seen the earlier results.
Gary: Well, that's really promising, Bill. That's music to my ears, because we all have those patients who are floating around and perhaps have been waiting for a new technology, a new treatment, that's going to be able to help them. If you were talking to a new surgeon who perhaps just got a Nidek laser and was going to start offering topo-guided treatments, what are some things where you'd say hey, here's some pearls or here's some things to look out for that I've learned along the way? What are some pearls you could share with some folks who are maybe either thinking about getting started or are indeed on the beginning of their journey?
Bill: Sure. One thing that I've found interesting was analyzing the topography. Initially, I thought the "perfect" topography would say, would be an all-green topo where everything, where it's a perfect sphere appearance. Ks 42 by 42, with no cyl, no irregularity. What's interesting is, we learned from Doug Koch’s work down in Baylor with this posterior corneal astigmatism, that since there is posterior corneal astigmatism and/or lenticular astigmatism, the ideal topography for most patients is a topography with about 0.50 D of with-the-rule astigmatism, about 0.50 D of astigmatism around 90 degrees. And initially I was looking at those and saying, "Well, gosh, I should bump up my cylinder to erase that and look for these predictive postoperative topographies being perfectly spherical or perfectly green, I guess." But, in reality, most patients have some sort of either lenticular and/or posterior corneal astigmatism that the anterior topography will need to mask or be in line with. I guess, don't be surprised if you're seeing the predictive topography in most cases being 0.50 D to 0.75 D of with-the-rule astigmatism as your potential or predicted final result.
Gary: Wow! Bill, that really makes sense to me as you explained it. The work on posterior corneal astigmatism down at Baylor I think has really opened up our eyes, no pun intended, to what may be going on behind the scenes. This really seems confirmatory. If what you're saying is really what's going on, it really does make a lot of sense why you'd want to leave a topography with some with-the-rule, because you're balancing out the against-the-rule posterior astigmatism. That makes a lot of sense.
Anything procedurally, or when you're going through and looking at the topography or, you know, analyzing it to make sure that you're getting a good scan? I assume that's kind of a no-brainer, but any other things or pearls with the equipment or doing sort of the preop workup?
Bill: Sure, yeah. I think having a well-trained and experienced technician taking the topography is crucial because you're going to be using that information to guide the treatment. Traditionally, let's say if there's a little dry spot or a little irregularity, it might not hinge as far as the final outcome but of a case with traditional LASIK. But with this, the scans are crucial. Initially we started with just one technician. That was her job, was to take the preoperative topographies. Initially, the first month or so, we had maybe a 50% capture rate, where half the eyes were not getting quality scans, and we weren't comfortable treating. But after time, experience, and education, now we're over 95% or 99% capture, where we have good, quality information that we're using to guide the final treatment.
I think taking great scans, analyzing the irregularity, how much irregularity is being treated. If it's a highly irregular eye, let's say a decentered ablation, you might have 10, 20, or 30 microns of irregular treatment being added to the cornea, and you should be cognizant of that. If you have 20 microns of treatment that's on top of your sphere or cylinder, there's a potential of over-treating your sphere portion, so keep that in mind.
If it's a 2 to 10 microns, it's a relatively minimal effect on your final sphere, but on the irregular eyes, you should look and see how many microns are being treated as far as the irregular portion, and where is that being laid down? Is it being laid down centrally? If so, then it may cause sort of a hyperopic end result, or if it's being laid down peripherally, it may end up being, let's say, more of a myopic end result. Or it could have the potential to inducing or treating astigmatism, so it takes a little bit more art as far as analyzing that and seeing where the irregular treatment is being laid down and how many microns are being placed just so you don't have it either over- or under-correction.
Gary: Well, that makes a lot of sense. I guess, in summary, your summary thoughts, is topography-guided here to stay? Is it for all patients or a niche? What would you say your summary statement is on topography-guided experience with LASIK?
Bill: Great, yeah. In summary, I think topography-guided is definitely here to stay. For us, it's been our go-to procedure for basically all patients, both more normal looking corneas and irregular corneas. I think we've learned it does great on the irregular corneas, but we've also learned it's a great tool just for the more regular, run-of-the-mill corneas, mostly because it allows you to sort of go through the process, map out, see where the treatment is, see what the effect is. It's one other tool to use to help with your decision making as far as, how much sphere? How much cylinder? Where is the exact access? You can use that topography portion as part of that decision making to more or less increase your final results or increase the chance of hitting 20/20 or better than 20/20.
Gary: Well, Bill, thank you so much for obviously all you do in our field, for being a leader in this area and taking some time out tonight to discuss it with me. I've learned a lot, and I'm sure a lot of people will find this very interesting.
Gary: This is Dr. Gary Wörtz with Ophthalmology off the Grid, and today I have with me Dr. Karl Stonecipher. Karl, I just want to say thank you for giving us a little bit of your time to talk about topography-guided LASIK, and the WaveLight system. I guess it's called the Countoura system, at this point.
Gary: If you'd give us a little bit of background of your experience with topography-guided LASIK with this system and maybe your experience with other platforms or other systems and maybe where you see this as a platform moving forward in your practice.
Karl: Well first, thanks for having me, and I think this is a great kind of format that you're putting together and I really appreciate that. For those of us that have commutes and drives and all that sort of stuff, we can hang out and listen to a podcast. I like kind of the casual atmosphere, but today what you've asked me to kind of talk about is my experience with topographic guided laser vision correction, which we have now called Contoura, or that's the new kind of trademark name that Alcon's going with.
Realistically, Contoura is not new, okay? We started working with this in clinical trials over 7, 8 years ago and, as you know and we've talked about, that it was approved in 2013. The roll-out, or the launch, has been extremely slow, but I started working with this obviously in the FDA trials. We got some of the best results we've ever seen with uncorrected distance visual acuity, but on top of that we've gotten some of the best results in terms of reducing glare, reducing halo, reducing some of these side effects that are unwanted.
What I’d like to do is educate the crew kind of where we're at in terms of this whole big picture. If we talk about a conventional platform, well, you use a Technolas, that's got a conventional platform, Visx has got a conventional platform. Well, realistically, WaveLight, when they first came out, they came out with this wavefront-optimized platform in the US, which basically allowed us to add pulses to the periphery, where we were losing energy when the pulse was coming in at an angle. Primarily what we did was we reduced some of the induced, you know, aberrations that we were producing, like spherical aberration, for example.
Then we go to wavefront-guided. I also have a Visx system, so if I use a Visx platform, it's going to be a Customvue, as long as I can get an appropriate Customvue. Pretty much, probably now 80% of my patients are done with the wavefront-optimized platform because it gets such good results, and then the other 20% now are this Contoura Vision. How do I differentiate? When do I do wavefront-guided?
We wrote the paper, Dr. Kezirian and I did, years ago, that basically showed if your RMSH, or your root-mean-sphere higher-order aberrations are 0.4 for sure or higher, they need some type of custom treatment. That's when we'll go back to that platform, so if it's 0.4, 0.45 or higher. Surprisingly, a lot of this is in the enhancements. You know? Some of these enhancement eyes that we've done their eyes previously before and they've come back and they've regressed or whatever.
With Contoura, what I'm trying to do is teach people not to go out and do all the 20/unhappy people. It is a true topographic-guided treatment. Why do I like it? Because we get larger optical zones. We can, outside the United States, treat some of these highly aberrated eyes, but that's not what you're trying to do in the US. In the US, we're approved up to -9.00 D with up to 6.00 D, and right now we're getting phenomenal results, but again noise in is noise out. You and I both know, if we get a bad refraction, we're not going to get a good result. We still have to work off that refraction, and then we also have to be able to get a really nice picture. You know? A topographic picture. Which can be the eyelashes, deep-set eyes, Neanderthal man, whatever you want to say.
Gary: Right, right.
That brings up a good point, that I really, through the years, even though I'm not intimately familiar with the WaveLight platform in my own hands, you know I've got a lot of friends who use the WaveLight Allegretto, they use the wavefront-optimized treatment, and they love it. For all intents and purposes, it's really hard to improve upon a platform that's so robust, that's so good, that gets great results, and it really, in many ways, is kind of like pushing the easy button. Because if you get a good refraction, you dial that in and there's few variables that go into that because you pretty much know if you get a good manifest refraction, you've got a great chance of having a happy patient afterwards with just the wavefront-optimized.
I kind of use the analogy that, you know, if you're standing on the North Pole any step you take from there, you're going south. At least with this platform, you know, improving upon something that's already just tremendous and fantastic, it gives us the opportunity at least, and this may be the reason why the roll-out has been a little bit slow. I have to give Alcon credit for that.
Karl: Of course. Definitely.
Gary: Typically, an FDA approval, you're waiting, you're waiting, you're waiting, and as soon as you get it you're launching.
Gary: I really have to give Alcon a lot of credit for saying, "Let's slow this process down. Let's make sure we get it right. Let's make sure that when this is rolled out to the masses we're not causing problems or having to really reinvent the wheel here." I really do have to give Alcon a lot of credit for being very thoughtful in the way they've rolled this out. But the question is, with topo-guided, as you mentioned, in the rest of the world, it's finding its place really in those either maybe forme fruste or questionable forme fruste keratoconus patients, where they're also doing some cross-linking, maybe someone who has a central island or a decentered ablation, or maybe a small optical zone and they're trying to make a larger optical zone for some of the problems that you've mentioned.
The approval for this Contoura system is really on the normal eyes.
Gary: It is contraindicated, at least by FDA standards, to use in those cases. I don't know if that is as much an indictment on the fact that getting through the FDA, you just have to find your spot and stick to it, or where this technology is going to be used? Even perhaps off-label, down the road. I mean, what are your thoughts on that?
Karl: It's simpler than that. One thing I want to do is not denigrate any platform, so right now you're 100% correct. We are getting phenomenal results across all platforms, and so I think that we always get this negative LASIK, negative LASIK stuff that's coming out and it's amazing the results we get.
You're right, to go to that next level, is this going to be a treatment for everybody? I have friends of mine, Mickey Gordon, Kerry Solomon, that are probably using this in close to 100% of their patients. A good friend of mine, Jerry Tan, close to 100% of his patients. But outside the United States, when we looked at this awhile back, it was probably about 20%, 25% of the patient population, but some people have now bumped that up to 50% of the population. You're picking and choosing the right person.
Now, the one thing I want to disagree with you on a slight point is central islands. It doesn't work well for central islands, and so what happened was, Guy Kezirian, in his infinite wisdom, when he was trying to design studies tried to do what we called the 20/Unhappy Study. What the problem was, was, let's say if you're 20/20 and you're unhappy for whatever reason. Glare, halos, whatever. We couldn't get an FDA parameter that they were happy to say, "You went from A to B, and that was better."
Gary: "You went from 20/20 unhappy to 20/20 happy."
Karl: Our infallibility was trying to find out a way to measure that. Now, the second thing is, in these highly aberrated eyes, most of the individuals, if they're using cross-linking it's in keratoconus like John Kanellopoulos, Arthur Cummings, Matthias Maus. The big picture with the highly aberrated eyes is, a lot of those people, like David Lin, for example, will say, "You have to treat these highly aberrated eyes just for their basic aberrations and their corneal problems, and then you come back and it's really probably a two-stage procedure, because you can end up + or – 1.00 D, and you and I both know if I reduce your aberrations and I reduce and make your normal cornea but you're a -1.00 D, you're going to say, "Well, you know I'm 20/40 now, and I can't see!"
Gary: Right! Thanks a lot, doc!
Karl: Yeah, exactly! Or if I'm +1 and I'm 40, it's even worse!
Gary: Right, right.
Karl: I think we're still trying to figure out the niche, and that's why I always say “do the easy peazy lemon squeezies.” I always say that any time you get a new platform. You've got DataLink to help you, which has got data. You've got Internet-based refractive analysis to help you, so there's a huge pool of data that if you're going to go pick up a WaveLight tomorrow, you can go and look and have an established nomogram with thousands of laser procedures in there. At least it's a good starting point, where when you and I first started off it was kind of, "Okay, we're going to throw a dart and see what sticks."
Gary: Right, right.
Karl: I think that's the biggest surgeon’s nightmare, because we have a lot of new users to this platform. TLC just picked this up, and some of the other big centers picked this up, and so I think that for the most part we're going to see a lot of people using the software and it's nice to be able to say, "Okay, this is a person I should start in."
I tell everybody, start off with -1, -2, -3. See what you do, and then slowly work up both with astigmatism and with nearsightedness. Then you'll get outcomes like, we're at 71% on day 1 seeing 20/16. On day 1, we're 20/10 in 10% of the patients.
Gary: That's another point. I've talked to some other surgeons, and they say with topography-guided, it looks like we're getting the most 20/12.5s, 20/16s ever, but maybe we're not getting quite as high 20/20. Have you found that in your practice at all?
Karl: No. We're still at 100% on 20/20.
I really think that the infallibility there revolves around the refraction. To step back, one of my pearls is I have two lanes that I refract in. I know what the vertex distances are in case I have to put in a ICL or we measure it in the patients, you know, if we're doing an ICL type thing. But I have two lanes with the really nice visual charts, like SMS or something from Lombard.
Gary: Right. It's not an old 2 projector with a bulb that's dim.
Karl: Exactly! You can't see!
Gary: A bunch of dust on the end of the lens! Yeah.
Karl: My staff actually measured 20/10 before surgery, so I can know if I lost the best corrected line, if they went from 20/10 to 20/16 or 20/15. And then basically I have two people that really refract. Now, I have 294 surgeons that refer in to me. We got all these physicians referring in to us, and they're optometrists, other physicians, whatever you want to say, but for the most part in those people we still re-refract them.
I look at you and I say, okay, I'd love to have your psychoplegic data, your manifest data, because I want to know if that's changed, but when they get back here you know it's kind of a measure twice, cut once thing. The patients love it, the doctors don't get offended, and you basically do the batter one, batter two thing on the day of surgery. It slows you down, I won't lie about that, but boy it helps with the results immensely.
Gary: Well, and that's another thing about maybe slowing you down. With the wavefront-optimized, it seems like you get a good refraction, you're pretty happy with it in the lane, you punch it in to the laser. Things are pretty simple, right?
Karl: Point and click, yeah.
Gary: With the wavefront-guided treatments, you know, you had to make sure that your pupil was the right size and then you had to look at the wavefront data and make sure that it was close to your dry refraction and close to your cyclorefraction, and then you've got to maybe change it a little bit in the computer.
What about this? It sounds like there's additional steps.
Karl: A lot more steps.
Gary: Maybe, from that side of things, it slows you down? We're willing to slow down if there's a payoff, so walk me through that a little bit.
Karl: That's what, basically, payoff from a monetary standpoint as well as payoff for an outcome standpoint. I've always kind of been one price for everybody, but we did bump this up in terms of the big picture because it does take more staff time to get a good picture.
Karl: Then, once you're in the operative suite, you basically look at, say, 8 pictures or 10 pictures or how many pictures you let them take, and then you look for continuity. If there's one that's like, "Whoa, that doesn't look like the other ones ..." It's gone.
Karl: You've got to physically do that, and really that's not something I don't think the technician can do. Am I opposed that the technician does it? Well, anybody's trainable, but my point is, at the beginning it's going to be the surgeon trying to figure out whether that topography is good or bad. Now, on top of that, then you have to go in and look and see what that topographic-guided treatment is going to do to the refraction.
Karl: You can look at it, and it's a little bit of art, and you can say, "Well, maybe that's going to induce a little hyperopia when I look at just purely what the topographic-guided laser vision correction is going to do." Then, so I back that off and I may add a little minus to it to see how that counterbalances it, and then I'll say, "Okay, that looks good, so I'm going to add that to the treatment." I think that's why Alcon's done such a great job with the slow roll-out.
They wanted to release it to, say, 10 surgeons and then see how they did with the software. Then once they got those 10 surgeons doing it, then they're trying to train those surgeons to train the next 20 surgeons, which will train the next 40 surgeons, which will train ... They're going to hopefully give you a tool, just like if I take you out to NASCAR. You know I'm from NASCAR, you know, so if I take you out and I put you in the car and you're going to go around the track at 170 miles an hour, if you hit the wall, it's my fault.
Gary: Right, exactly.
Karl: Because I didn't show you how to shift, I didn't put you in the car, drive around a little bit, and make it to where you feel comfortable before you jump into this stuff. I think it's a bit Ferrari-ish. I mean, you're going to that next level of, what do I got to do with regards to my nomograms? I've already said that Ibra Software, internet based refractive analysis, and DataLink, Guy Kerzirian’ss software, both help you get there faster. You know?
Karl: Once you got your 50 cases in, you're probably using your own stuff, but I mean those first 50 you want to start off slow, low, and then last but not least I think you and I have to figure out, "Okay. What is normal, and what's abnormal?" That goes back to the wavefront-guided. We had a measurement of, it was .4 or higher I kicked them over to the wavefront-guided. Wavefront-optimized, everybody else. Now we've got this new set of, say, 20%, 25% in my practice of patients we are using this on. Mickey, like I said, is using it in 100%. I think Kerry’s close to 100%.
I think it all depends on where you want to go, because it's going to give you much larger optical zones. That's the number-one issue that you're going to see in people. We wrote a paper years ago, Guy Kezirian and I did, about pupil is not really an issue with the newer design. If somebody comes in and says, "Oh, I got a huge pupil." Does that scare me to operate on them? I'm sure you agree, it doesn't.
Karl: I think for the most part now, what do patients benefit most from with topographic-guided laser vision correction? I think they have to have a little bit of irregularity. If you look at it's all green all across it's going to make a larger pupil. I mean, a larger zone, optical zone.
Gary: Optical zone? Right.
Karl: I think for the most part, I don't know if that translates into anything because we haven't really looked at that per se. We did, like I say, get some of the best outcome satisfaction rates with these patients in terms of visual quality. Not only quantity, but visual quality, which was cool.
Gary: Right, right.
What about PRK? Are you using this with PRK as well? Have you noticed any difference between PRK and LASIK that's topo-guided?
Karl: I think in terms of PRK-driven topographic-guided laser vision corrected is what a lot of these guys are doing in the highly aberrated eyes, and I think it takes away some of the issues with the flap. Plus, some of these highly aberrated eyes, they come in with like six different treatments. I had a guy the other day came in with 64 incisions on his cornea. You know, and you're like, "Uh, really?" I counted them. I was fascinated.
Gary: Was there any gap between, or was it ... ?
Karl: Not much, and there was a lot of crossing going on, too. I think that, for the most part, if you're going to do a virgin eye, you can get away with LASIK all day long as long as you've got the appropriate anatomy. I think there's a lot of people that like PRK, and so I think some of these military types are still more prone to say, "I want to do PRK." An MMA fighter, you know, a karate guy may want to do PRK. I still see people walk in asking for laser vision correction on the surface.
Gary: Right, right.
What about any difference with how tissue hungry the platform is? If you're going with a topo-guided treatment, is there any issues with maybe you're taking away a little bit more tissue? Does that concern you? Is that something that might drive you towards one treatment versus the other based on, like, residual stromal bed thickness?
Karl: Yeah, and I think that there's a latest paper, Santos I think published it, and it's always been my thought process. You've got to leave a certain percentage of the cornea behind. I think that taking 300 microns in a 600-micron cornea is different than taking 300 microns in a 500-micron cornea.
Karl: So, yes, there is a little bit more tissue, especially when you're doing these aberrated eyes. A lot of the guys that I work with, David Lin, Arthur Cummings, you know, sometimes you may have a -2 refraction but in fact you may have a 12-second treatment. Well, this laser's taking off 2 seconds per diopter, so you like go, "Ooo. Well, that doesn't make sense. It should be like a 4-second treatment, why is this all of a sudden 12?" Because of what it's doing in the periphery, but that's where you get the refractive surprises.
Gary: Right, right. Okay, very good!
Well, thank you so much. You've given us so many pearls. I feel more educated about the platform, where it's at right now, maybe the way to start and maybe where we're headed with this platform as well. Karl, I can't thank you enough for taking some time to talk to me today, and just want to say thank you!
Karl: Hey, thanks for having me!
Karl: I think it's a new, cool way to transmit information.
Well, this has been Ophthalmology off the Grid with Dr. Gary Wörtz. Thank you!
Gary: Thanks for listening to this episode of Ophthalmology off the Grid. I love having the opportunity to get some of the best minds in our field together to hear their thoughts on the latest advancements in treatment and technology. I hope you enjoyed hearing what they had to say and were able to take away some pearls to use in your practice. If you'd like to hear more episodes, please visit us at eyetube.net/podcasts.
This is Dr. Gary Wörtz. Until next time.
Speaker 5: This episode of "Ophthalmology Off-The-Grid" is supported by Centurion, by Alcon.
8/15/2016 | 57:16