 I think everyone in the VA can hear me when I talk to them, so. Well, thank you very much. The title of my talk is Future Advances and Infractive Surgery. The future is in sort of semi-quotes because the two things that I will possibly talk about, certainly the one, depending on how much time we have, people are already doing both of these things, we're just not seeing them in the US. This is a picture from Nepal, it's a fourth year med student, I spent a month out at the Tolkanga Eye Institute, and that's actually where I first kind of learned about the first refractive procedure that I'll be talking about, so that I don't forget. Acknowledgements are very important to this talk because a lot of the information data and a lot of the images are courtesy of Dr. Rheinstein as well as Dr. Kishore, who are both kind of worked in conjunction to set up the Eye Center and the Refractive Center in Tolkanga and then Dr. Mehta Singapore and Dr. Moshfar here, who I spoke to a little bit. So the outline of my presentation, we'll see if we get to the bottom half with time, we may just do the top half, but what I'd like to talk about is small incisional and ticule extraction that's named SMILE. It's a procedure that's been around in the literature for about the last three to four years and presents some of the initial data as well as some of data that's not published yet but is out of Nepal and has a little more power to it in terms of the numbers of patients. So what is SMILE? I figured before we start talking about it, it would make most sense to try to figure out exactly what it is. So first I'll show you a little animation and then we'll show you kind of a surgical video. In essence, what you do with the procedure, it's an all femto refractive surgery and so you're cutting a lenticular or a lens so you cut the post to your surface first and then cut an anterior surface with the femto second laser. It produces a lens shaped or lenticule. Then you make about a four millimeter side cut incision with the femto second laser as well. This animation doesn't show. It will just pull that out. That lenticule does not just pull out. You have to do some dissecting which you'll see on the surgery. But you dissect anteriorly above the lenticule and then posteriorly above the lenticule. Thank you, Zeiss, for that wonderful interview. And then you're able to pull that out. So this is just a quick video. I won't show all of it but part of it from Dr. Kishore and there'll be a little freeze in this video. It doesn't actually take as long but this is again, you cut the posterior aspect of the lenticule which is slightly deeper in the corneal stroma than typical Lasik or PRK. Then you'll cut the anterior. There's not actually a pause like this. I think this is just a video. It gets caught up on YouTube but then it'll continue to oblite the anterior surface. And you'll see that the anterior surface, it will go to the edge of the posterior and then extend farther so that when they make the side cuts, you'll be able to gain access to the lenticule. And you'll see there's actually two cuts that are made. So there's one four millimeter about side cut that's made here. There's also about two, I think it's two or two and a half millimeter depending on the ablation profile that's cut here. Most times that is not opened up but it can be if you're having difficulty dissecting the lenticule out. And then the actual dissection. So then you obviously, this is actually usually done with the at the slit lamp that the patient's sitting out with the microscope. So you'll see, you'll come in and you first dissect where that side cut is at. He'll dissect over the anterior portion first right at the lip of the lenticule and then he'll dissect posteriorly underneath the lip of the lenticule. And you'll see because it's sort of a photodisruptive mechanism, there is still some adhesion but it'll get that clear. And then once that, he has the initial lip cleared, then he'll proceed to kind of dissect over the entire anterior surface and then the entire posterior surface. And the whole process takes probably for each eye generally about, I would say like two to three minutes and most of the procedures that I saw him watch and most of the YouTube videos that you'll see, you'll see that he'll make sure that he extends all the way out. The one thing that he's very careful about and that seems to be very important is to make sure that you're not leaving any in essence tags of the lenticule that could cause a like post-operative astigmatism because you would have some retained lenticule in there. But so you'll see he'll dissect anteriorly and then I'll jump ahead just a little bit. I think actually he might have dissected posteriorly when I was talking. Okay, and then you'll just see he'll go in, he will grab the lenticule and then remove it out. And you won't see it here on this video because this one ends before but typically then what he'll do is he'll put some BSS on top and then in essence lay that lenticule back out over the surface to ensure that there's no tags or any retained parts of the lenticule. If there is then you would kind of coordinate that based on where it is and try to go back in and find that the time size on there was never a case where that happened. So, Sam, I don't have any questions about the procedure itself. So I wanted to spend just a little bit of time talking about a quick review of the literature in terms of the data that's. Just one thing is. Yeah, okay. The initial data, there's been kind of a bunch of different people that have published data. Secundo, I think, was the first one that I sent found that was out of Germany. He was actually, this was prior to when they were doing the small incision, they were actually still creating an entire flap but they were still cutting the lenticule. So they were cutting the lenticule and then a flap, flipping it over and removing the lenticule and then putting the flap back down. And his initial data that was back in 2008 showed some relative success. Although, and you'll notice, A, there's very small numbers and most of the studies that are in the literature right now and a lot of times the sort of reliability in terms of how close they are to their predicted target outcome isn't what we see necessarily in Lasik in this country, which is why there's been some concern about it. Dr. Shaw published kind of the first, to my knowledge the first data that was on the actual small incision portion of it. She had 51 eyes. Her results were kind of concerning to a lot of the refractive surgeons here, which is why I think it'll be a while till it catches on but her uncorrected distance visual acuity was only at 80% at 2025, which is relatively poor compared to the Lasik outcomes that people are getting here. And so there was a lot of pushback. There was also two eyes that lost one line of corrected distance visual acuity. Certainly you don't want people losing two lines with even one line is and most of the refractive patients would not be appreciated here. Secundo did a follow-up study in 2011 where he was actually using the small incision technique and you'll see that he actually published a lot better results than what Dr. Shaw did in terms of outcomes and in terms of you'll also see by doing the small incision versus the entire flap that the percentage of patients that are within kind of the target range of one diopter and or half a diopter are a lot closer than they were previously. There's some thought that that also is due to sort of the ablation pattern and some advances in the technology as they've learned about and studied the best technique for the ablation pattern. So the thought right now is that you do always do the posterior surface first but you go from peripherally to centrally and then on the anterior part you go from central to peripheral. And that's been shown in a couple of studies to have the best outcomes. One other one that was recently in the JCRS from Kazutaka in Japan who actually showed very good results in terms of uncorrected distance visual acuity. And I didn't really see in looking over that paper a great explanation for why they felt like they were getting so much better results than what's been previously published by Dr. Shah as well as the group in Germany. But they had uncorrected distance visual acuity of 2020 in all of their patients, which was 38Is. So there's some evidence that maybe with the new improvements in the ablation pattern that there might be some improvements in the outcomes. Also interestingly, I thought they did two other things that they wanted to check on. The first was the stability of the manifestor fraction and so they only have six months follow up but you'll see that at the like about one week to one month time period compared to the six month time period you have pretty good stability in terms of the spherical equivalence of their eye. And they also looked at the endothelial cell count because there's some thought that this is a deeper ablation than you have with either LASIK or PRK so that you're more at risk for having damage to the endothelial cells and there had not been any evidence prior to this about the sort of documentation of that. And they found that while there's a slight decrease that's statistically significant and there doesn't seem to be significant damage. The next thing I wanted to do was just present some results from Nepal because one of the things that a lot of that data had was very small power in terms of their numbers. This is Nepal one day results. You'll notice that the end on some of these results is different and that's mostly because some of their data they haven't kind of gotten through so I talked to Dr. Kishore and got some of it but not all of it and it's not published so it's also, there's some, it obviously isn't peer reviewed yet and been completely looked at. How many eyes are we talking about? So this is just 75. The next. 75 for the entire form. This is just the smile part. This is for the smile part. And actually you'll see I don't know why they don't have more one day data because the next one which is one month they have 320 eyes in the smile which we'll go over. But as a demonstration the point being that their results in terms of a one day prognosis are similar to LASIK and the thought process is similar to PRK or unlike PRK you're not disrupting the epithelium and so that these patients typically do have relatively decent vision at day one already which is something that's appreciated. They're one month data again. I don't have a good explanation for why the ends are so different but this is looking at, I think he's done close to 800 now in the entire year so this is kind of the first three quarters of the year the data that they've processed and looked through but 320 eyes and smile and 118 at LASIK this is all at their refractive center there. Of note what you'll see is there if you're looking at post-op uncorrected distance visual acuity compared to pre-op corrected distance visual acuity the results that they're getting in terms of LASIK and smile are relatively similar. He doesn't have the six month data or year data available yet and obviously that will be important to look for but it seems that the data is definitely better than what Dr. Shah was initially reporting and that there may be some future for this. Predictability is also an important thing and this just shows some regression models and just demonstrates that both with the LASIK and the smile you're getting kind of similar predictability in terms of your outcomes. Most importantly you'll notice one of the things that's been mentioned with smile previously and I'll go over why they think this is is that you can target higher refractive error or higher myopia and still feel that you have some safety without risk of ectasia and I'll go over why that is but they have ablation patterns up between minus eight and minus 12. Obviously there's importance of sort of safety safety as they consider it is sort of not losing uncorrected distance or corrected distance visual acuity. What you will see is then smile they have had at least one patient that's lost two lines and they've had some that have lost one which is greater than what you see in LASIK so there's still some concern for why that's occurring and they don't necessarily in talking to Dr. Kishore he doesn't have a great explanation necessarily at this point for why that is whether that's something to do with the interface of the two femtosecond surfaces coming together or what that might be. I wanted to spend just a little bit of time going over some of the potential advantages of smile and why I think we'll probably see it here in the US and that it may, I don't know if it'll take over sort of what LASIK and PRK is but I do think we'll see it becoming more evident. First thing is you have a decreased incidence of post-op dry eye or kind of post-op neuropathy of the cornea and I'll explain why that is. There's some biomechanical advantages there's decreased risk of flap complications now you still have a stromal bed that's in there and so you could still have epithelial ingruth but you don't have the risk of the flap dehistons and then it only requires one laser as well which maybe from a business perspective as more practices are using femtosecond laser for cataract assisted procedures you may see more interest in this as well because you just need the femto for it. So a little bit kind of about the reasoning why there's thought to be less post-op dry eyes or post-op corneal neuropathy in essence what you're doing in smile like I said the stromal lenticule is a little bit deeper in the cornea so you can see here you know your posterior surface generally they try to set the stromal cap to be about 130 to 150 microns can go a little bit deeper depending on the patient's cornea depth but you have it by doing that and by not cutting an entire lasik flaki the theory is that you preserve some of the corneal like sub-epithelial nerve plexus and that the patient then will have greater residual sort of corneal sensation as opposed to lasik which is more a cutting through and transecting when you make the flap that entire corneal nerve plexus and Dr. Reinstein has just done sort of a relatively small look at this that's not been published so again it's not completely peer reviewed but of 39 eyes that he had after smile procedure and using this kind of cochette bonnet I don't know if I'm pronouncing that right is the elmeter to look at in essence a monofilament for the cornea and looking at the results and kind of comparing it to a bunch of lasik studies that he's that kind of have measured that and what he found was in comparison to sort of the average of all the lasik studies that he looked at was that especially at day one or day zero kind of you have a significant improvement in terms of the corneal sensation there's still a reduction whether that's because you're still transecting some of the nerves or it's just from the manipulation of the dissection as you can see in the long run at six months out there's probably not a whole lot of difference but for a short period of time anyway you have a decrease that appears in terms of or an improvement in the corneal sensation the other thing that I wanted to mention which is why I think we'll see it in the United States is that there's a theoretical sort of biomechanical advantage to the procedure and why we can do it in higher myopes there's been one of the studies that Dr. Rheinstein quotes a lot and I think is an interesting study that was looking at sort of the tensile strength of different stromal fibers from the anterior cornea to the posterior cornea and what they found was that there was a sort of negative relationship in terms of the tensile strength of the corneal stroma so the anterior corneal stroma has greater tensile strength than the posterior cornea and if you kind of look at it if you estimate kind of going from about an 80 to maybe about a 40, about a 50% like I said you could view it as a 50% decrease or 100% increase in terms of the corneal strength and so the idea is that with lasik when we do lasik we cut a flap as well as ablate the anterior surface or in essence kind of taking out any strength that we might get from that anterior stroma in terms of preventing risk of ectasia and we have preservation of sort of this posterior stroma that's back and behind whereas with the smile procedure that in theory the thought is that by cutting the lenticule and just making a small incision you still have some preservation of some of these anterior stromal fibers which have a little bit more tensile strength you still are ablating the central part and leaving yourself with some posterior but that there might be decreased risk of ectasia after a procedure this is sort of, I like to call it maybe some funny math but this kind of illustrates maybe the concept or idea so the thought process is if you have a if you take an example of a 500 micron cornea and you ablate 150 microns of it with a 100 micron lasik flap you in essence have a residual stroma of 250 because with the flap you're not really retaining very much strength from that anterior stroma whereas the thought is with smile again about 130 micron cap would leave you with about 80 microns of stroma anteriorly that still has some stroma integrity and tensile strength to it you have the residual stroma of bed that's slightly less than in the lasik but if you do combine these because you're saying that the stroma does have some tensile strength remaining you have an equivalent total of about 300 and if you also factor in the fact that that anterior stroma theoretically has more tensile strength you could possibly postulate that you may actually have an even larger effective total and that's the thought process for why you could treat higher myops without with a decreased risk of ectasia so here's just a quick summary of those advantages I think it'll be interesting and I think there's my understanding is there is some FDA trials that are starting here in the states but that there's no real published data about them certainly there's risks and considerations that need to be made obviously there's really no significant long-term data so lasik we have a lot of NPRK significant data in terms of 10, 20 years out and this we don't really have that you also have a limit of about a one diopter correction because you're making a lens or a lenticule you have to have at least some depth to that lenticule to be able to dissect and anterior and posterior surface and then from if you are a refractive surgeon in concern one of your oftentimes patients want touch ups and there's no real way to touch up a smile procedure by doing another smile procedure because again you would in theory need something less than a diopter so another problem that I definitely see with this is that if you do need a touch up then you end up needing to do PRK or needing to do lasik and that takes away your advantage of only needing one laser as well there's a concern about in my mind anyway that there's some documentation of some loss of vision and then there's a question if you have the two photodisrupted surfaces of from the femtosecond laser there's some people that think that that interface could cause people to have more problems with sort of rainbows type skitomas and sort of diffraction of light as it goes through Dr. Kishore hasn't had that reported by any of his patients yet but it very well could be something considered. Future directions of this procedure so the group of Singapore is actually currently doing a randomized non-inferiority trial between smile and lasik that hopefully will be published here in the next year or two I think it'll be interesting to see the results of that and try to establish whether there is a difference between the two. Currently like I said there's no real published large data sets I know that Dr. Kishore is planning on publishing his results I think once he gets it was about 800 patients kind of total to compare and just because I thought it was really intriguing and totally off the wall it's also a group that studied the feasibility of actually re-implanting the lenticule they did it in rabbits but they actually took out the lenticule stored it for like 28 days and then re-implanted it and looked for any sort of interface issues or inflammatory reactions and then after they had re-implanted it for 28 days they killed the rabbits and investigated them and kind of took a look and they didn't see any sort of interface or inflammatory reactions the thought process is that maybe you could preserve those and save those if the patient did develop ectasia that there might be some I don't really think that it would be of benefit but who knows maybe in the future sometime there'll be something with that I will not go I was going to talk about laser blended surgery for presbyopia but we don't have time for that so I'll just end on my public service announcement from Nepal and this is to make sure that my talk is relevant to everyone so you need to make sure that you're eating your fruits and vegetables because if you're an anterior segment surgeon if you don't you're going to get cataracts and you also probably get macular degeneration because you're not having your vitamins and Dr. Krum will be very interested to know that your skin gets horribly worse and that you probably are going to need eyelid surgery and from a neuro-optimologic standpoint they definitely have vitamin deficiencies that could cause neurologic findings as well so I will end there so that we end on time and just ask if anyone has any questions at this point yes so obviously the theoretical problem is is that however you create this if you're going to also create a refractive error you're going to have one length of your posterior curve that is a different distance than your anterior curve but I'm sure those who are losing vision that the settling of that is causing some type of fear you've got that theoretical problem and it's not like when you're doing a lazing flop where you've got room for room movement on a perfect and it's fixed on the outside so I think that I'm impressed with the results I've seen and I thought it would be a much bigger problem than it appears to be and then you also don't know what's going to settle you've got your posterior cornea it seems like and certainly if it's weak enough it's going to move up and you've got your collapsed anterior cornea and those two effects depending on how they go yeah I think that's fair and they don't really have any great data in terms of published or that Dr. Kishore provided in terms of the residual astigmatism in their patients mostly it was just spherical so interesting to see yeah Jim I know that there were no yeah when I was looking through like all those previous data all the previous kind of published data there hasn't really been anyone that that I saw that looked at sort of higher order aberrations afterwards mostly they were looking at corrected there's a few people then that then started to do the endothelial count and looking at OCTs of the interface but I haven't seen any published data there have been some reports and sessions in the harass and there's definitely increased in higher order and that would make sense but I'm sure that there's going to be some qualitative difference and remember if you're looking at qualitative difference in regards to vision often some visual acuity is not the best is not the perfect way to look at that and so I think some of the ways of looking at contrast sensitivity are certainly going to be I mean you can't you can't have one curve or the other and not have some new patch yeah whether that's important or not the time will tell but no it has been looked at and I do get it yeah yeah yeah I mean so when I was out there I think I watched about 20 of them and yeah I mean most of the patients you can see kind of from the post-op data but most of them day one were like very happy and they sort of have an interesting setup in Nepal where they're trying to do a lot of them and so they have pain patients but they were also doing free refractive surgery on patients as well also be interesting to see if you start to see sort of medical tourism related to that sort of an aside but you can go and have smile done for I think about like 400 or 500 US dollars in Nepal so you can have a pay for your flight and have a cost about the same and get to go to Nepal so I do know that the victims of BNL masks the ones with the lens acts are all set up and they can do this procedure they have a curved interface they have an ability in a slight downside to the water of the interface machines that maybe have been paged so much for cataractivity and you're on the other victims are already doing it doing it all right thank you very much