 can tell you that when I was an intern that we had a guru that had kind of this little hippie community in New York and he believed that the the most important thing in life is to eat brown rice but nothing but brown rice and and then we brought in a very very sick person from this commune with severe vitamin A deficiency I'll never forget as an intern corneas were gone and the lens had popped out and the fact that they would just continue to let this person with this obvious sear affliction or just more brown rice more brown rice really brought to me how bad vitamin A deficiency can be. Alright so we set this is ready to go this is a series of projects that have been done a lot of medical students and residents who were involved in this and you kind of a little bit of an interesting story how sometimes very small things in cataract surgery can result in some pretty substantial you know I think positive benefits. So we're so used to those of us who are involved in cataract surgery a lot of talking heads out there and they'll sit there and they'll say well I think product A is better than B no I think B is better than C and you and I happen to know them well and I know they're getting paid by A, B or C to say and I hear them in the same in a different venue because now it's a venue they're getting paid by B and all of a sudden B is better than A and there's almost no objective information of what's better than another and it's certainly something that in my career that's always bothered me about you know we got to get some objective information so that we can really start saying what's better and what it means. Well Steve Dewey's a good friend of mine. Steve has been a very straight shooter and Steve came up with an interesting concept and what he said is is that when you take a FACO tip and obviously we know the risk for capsular breakages when we engage the tip with their FACO with the FACO tip when the capsule is touched he said we've always felt that that tip should be sharp and by sharp if you look at it what we mean is is that it's it's very tightly machined so that this little edge right here internally and externally is crisp and that's going to be important in regards to the overall cutting effect of the tip but his thesis is that also means when you have motion if you contact the tip you are more likely when you engage it to break it and the little modification that he did working with Larry Lacks at MST as he said let's take that same tip only we're going to radius and we're going to round both the internal and external edge of that particular tip everything else the same so it's really a relatively minor change and that that makes it much more capsule friendly and much less likely to break the capsule that's the thesis and he's talked about this he's even did a little work here where he did some video but really nothing objectively that showed that that made any difference now I'm a big believer in the law of unintended consequence and that is is that whatever you gain on one side what do you lose and on the other side if we think indeed that the tip edge is critical for its ability to cut and shave okay maybe we're being a little more capsule friendly but also we're losing a lot of efficiency we're losing a lot of the important effect that that tip needs to provide so we'll start out with any validity claim can such a small difference really protect the capsule what's the price so I'm going to take you through a series of experiments we've done to answer all of this and I think we've got a pretty good idea in regards to just what that minor change of that tip and what it really provides so this is kind of fun and this presentation I gave there was how clinical studies can be fun and how you can think about these things and how it doesn't necessarily need to be horribly complicated to come up with answers we know caps are to break you obviously this is this is a a significant problem lots of things that can occur in association with it and so we started out with you know trying to do a clinical study as just so many uncontrolled variables that go on how could you say it's just the tip that's associated with these changes and it would be a very large study to do so we said can we take some fresh human lenses just right out of the eye bank and and just try touching them because it's that initial contact it's the biggest risk and see if there is indeed a difference between a regular tip and a dewy tip so we started with fresh human lenses want a pretty good vacuum figure that vacuum the higher the vacuum the more likely you're going to have a greater force good bottle height good flow all the kinds of things that we know are more likely to cause caps that are breakage and then the idea is you just tap this intact lens and human lens and tap it until you break the capsule okay sounds pretty simple and straightforward biggest problem we had in as we ran it we ran out of fresh human lenses pretty fast didn't take long but we've got some interesting results here run out before we could test that box in that box but ellipse and ellipse is a motion of the tip which is very interesting there is some vertical and horizontal and actually the tip if you were to measure it over time will will subtend an ellipsoid so kind of think of it a football but it's a full ellipse you don't have those pointed ends that that's where the tip's going to be we know that Ozil will actually subtend an arc going back and forth an edge of an arc it's moving in shape but very much just wags from side to side so we found out that when we did the dewy tip we had to tap on average 47 times when it was sharp for 10 full difference in regards to its likelihood to break the capsule and that was highly statistically significant we did longitudinal 6 millisecond on 12 millisecond on fairly common micro pulse type and that also took 47 taps we didn't have enough to do the sharp Ozil at 100% power these both 100% power was 22 not enough to be statistically significant because the number we had was not large but suggested maybe there is a difference in regards to power modulation our likelihood to break the capsule so we couldn't do all we wanted to do and get lenses it was going to take us 30 years of how many lenses we get through to try to finish all that off so we needed a substitute we want to know a little bit more about this transversal and torsional which are just Ozil and ellipse who want to know what what tip bore size I always felt that most likely the larger the bore size if you contact it you're going to have a greater overall suction area holding it more like you're going to break it and can you break it without ultrasound that's always been a question of people had if you just engage it you also need ultrasound at the same time to break the capsule so this is result that happened from a very low-tech solution it's stretched Saran wrap on a copycat and it correlated fairly well with what we already had done with those human lenses and even though it may not be exactly the same at least the likelihood of breaking should be relatively similar so not perfect but the best that I think's ever been done and and for some reason nobody's repeated or looked at this this is probably the only study it's an American journal of ophthalmology that looked at this specifically came out about 2010 so here's the different sharp think the regular tip dull think of a dewy tip which radius along the edge and the first conclusion we could find is every time we did this the difference between a rounded edge tip and a regular tip was very substantial at least not twice as good it was usually 10 times better or more so indeed Steve Dewey's concept of not having a sharp edge tip seem to make a big difference every time we tested it and so we did prove that element of his hypothesis and that is it is protective of the capsule some other interesting things we found is that yes in general you're more likely to break it with a 19 gauge than a 20 gauge as you can see 92% 58 that was highly statistically significant and that you could see that as we move down and so what we've got here in the dull tip we're so small you can't get statistically significant differences that those are very very unusual that you're going to be breaking it and this is per 200 taps so we did 200 taps on each one of these to get a lot of numbers we also found that when we did signature and so this would be with a signature 6 milliseconds on 12 off micro polts we found out that 10% power it was not nearly as likely to break as you 100% power you were about the same ellipse and Ozil you can see at sharp were about 60 65 60% and then again it dropped off but something happened with Ozil it got more common with 20 gauge what's that all about so it actually answered some questions but left a mystery for us to explain why theoretically 19 gauge should be more likely to break which we were able to indeed prove but the somehow with Ozil it's flipping in both instances it was worth with it it's worse with a 20 gauge so all of these things were conclusions we'd had and come up with what's this going on here with torsional that for some reason that a 20 gauge was more severe and this is a long story and this is actually relatively long talk and I'm going to jump right to the chase on this what we found is is that the newer cartridges in order to try and minimize post occlusion surge which is a positive have a negative side effect and that is that the active vacuum at the tip unoccluded I mean I was taught long time ago that with a peristaltic you essentially had no vacuum at the tip until you occluded it but inherent in these systems to control post occlusion surge is enough friction that the measured vacuum unoccluded at the tip can indeed be as high as 245 millimeters of mercury now that's getting up the same as Venturi so that our thought that there's a I think part of the reason why these machines are acting more Venturi like is they actually are more Venturi like they are more vacuum based than peristaltic once you're getting that kind of vacuum in particular as you move from a 19 to a 20 gauge and you do the math all of a sudden the overall net result on the capsule flips and you're getting greater overall force on the capsule with a 20 gauge I think that explains that particular difference notice also that when we get more restricted in the system we're also going to get less flow so we're not getting quite what we need I think these are just examples of how you need to understand that everything that you do that may have a positive you got to look to see what the negative but the other side of this may be and that's what we found with that now in both the human lenses as well as the capsular substitute even with these aggressive parameters we never could break either without ultrasound so I do and I'm not saying it's impossible you know and looking at videos though it appears as though it's contact plus ultrasound is what breaks that capsule if you just if you just touch it I'm sure I'm you know if one of you residents is going to poke hard enough you can break it but if you recognize you just touch it and you pull away it it takes ultrasound but with ultrasound there's no question there can just be contact and it's going to break I do think a wagging with a sharp tip back and forth and how we use it we tend to use it at higher energy is more likely to break the capsule and I've seen a couple of clinical studies I haven't seen any published but I've seen some presented suggest the same thing that the risk with contact may be two to three times higher with that wagging horizontal motion I don't know we have enough to differentiate both whether Ozil and ellipse are different from each other but I do think in comparison the longitudinal there is an increased risk with contact and that's worth doing some additional studies which is frankly something I'm in the planning stage of right now so capsular contact with active ultrasound is risky business radius tip very protective we're able to confirm that in that late latest peristaltic systems can have been sure you like active vacuum actually use torsional and I don't know if we can see transversal or Ozil is different may increase capsular breakage risk but what are the downsides remember and this is the paper came out a 20 10 and now we need to understand but but what mechanically are we losing okay I mean we've lost sharpness and is that sharpness important for our ability to cut so this is a more recent study I got some of the residents here in the room involved in this and a nice paper and this is what price then is with sharp tip does this impact cavatational energy what about chatter we got increased chatter associated with us that's bouncing away from the tip when that fragment bounces away from the tip you got two problems one you got to go find that particle again I think searching around trying to find things that when you often get near the capsule so you're putting yourself at risk for contacting the cap capsule but we also showed in a in a very nice study that Jeff Petty and was involved in with some medical students that once you have gross chatter you dramatically decrease your overall efficiency so that the amount of time it takes in a control fast and remove these particles can take a lot longer and again a nightmare study to do clinically you just got so many variables and the numbers in order to do a power assessment is so huge because of all those variables it would be very hard to do looking at your regular cataract surgery so the solution start out with a couple of nice studies done and the first one is that we needed some fresh brinescent human nuclei and Jeff Tabin we told him we need it and he brought about 60 back from Africa so he's gonna be pretty hard these are gonna be on the much harder side that you normally have we need to make sure we've got something relatively controlled and then what you do for efficiency it's pretty simple how long does it take to remove a fixed-size particle you can do that in repeated fashion and then is it gonna bounce off the tip we call that a chatter event how often does that happen obviously you want efficiency means as short as seconds as possible to remove a controlled size but you don't want to do that with chatter where it's a bouncing off the tip it was a couple of students who worked over a period of time Griffin Jardine some of you remember him he's now at University of Oregon as a resident really did a lot of this work but came up with a pretty slick little system of using razor blades where you can take a lens you you've got to have a lens that's relatively hard can't just take a lens it's coming out of the the eye bank and do this but hardening either pig lenses which is something that later these are the human lenses that you put them in a little area that's kind of lens shape you cut them into fragments so you cut them in one direction turn them around cut them in the other direction and you end up getting cubes that are roughly two millimeters on the side then you can put all of these cubes together when you gonna do runs shake it up so you've randomized you can have some a little harder some a little softer you randomly pulling them out and now you've got a controlled experiment that can start getting you some data really comparing things to see what's better and what's not and you can do this in a very controlled fashion pretty simple set up set it inside of here and that normal little container we use wait till you've aspirated up to the tip and then once you've got it aspirated you hit full pedal down whatever your settings are every time it bounces off as a chatter event don't count the time you you only count the time that it's sitting at the tip for your efficiency but you also count each chatter event and Trent 10 to 20 runs for modality 10 runs is generally what we did with these human lenses because we had a lot we wanted to study in and somewhat limited amount of material in it's controlling parameters in a way that's very hard to do in patients so this is the DeMille study came out in JCRS 2012 nobody's ever looked at this in this detail you can see we tried to look at a lot of different parameters I just want you to notice because this isn't the main we're mainly talking about the Dewey tip is the broad range that you see here in regards to efficiencies looking at the same technology I mean look at Ozil IP which is kind of the latest variation we can go from 38.4 down to 4.9 seconds just based upon what the parameters are parameters are critically important I could design a study knowing the information here which I could make any technology look better than the other just on how I adjust the parameters so just because somebody shows that one thing is better in the other and tell you know what parameters and to me you have to show you've optimized the parameters so you're really comparing apples to apples and that doesn't happen and that's part of the reason why you'll get a saying I'm better than B and B better than a because they purposely I think have set it up to where they're gonna win they're not necessarily looking at what the objective site is anybody who says these these technologies that wag side to side cannot have chatter you can see there are ways to minimize it but you could also get a lot of chatter depending upon what your overall event is the cool thing though is is now we started having technology we could look at it even better this is a correlation between efficiency and chatter which was highly statistically significant remember we measured efficiency not counting the time when I had bounced off the tip and yet whenever you you're gonna have a chatter event you're also gonna dramatically decrease your efficiency and I think because you've got micro chatter that's where you watch that tip those of you done cataract surgery sitting at the tip but it kind of bounces you see a little bouncing around there until you feel it kind of suck in and then usually it disappears micro chatter is also a major cause of inefficiency in removing these particles so the second phase is because we can't keep expecting Jeff Tabin to come up with a you know 50 60 lens nuclei every time you wanted to test this is could we come up with a technique to harden pig lenses to get a similar effect overall that we were getting from these human nuclei and it's really a very nice piece of work that was put together it's a variable time soaking and formalin and then in BSS for 24 hours you get a consistent hardness then you got to use them cutely after that you can't wait very long or you can you'll start getting softening and changes in the lens again the same overall idea cut them 2 millimeter per side mix them all up together and now you've got a randomized way of doing some very good comparative information so beautiful piece of work here you can see that this is the pig lens itself they're hard enough you could cut them up relatively well and this is how hard they are and we just little test by crushing them to half their thickness and we had our results from the original human lenses with a standard deviation here and you can see two hours does it and and so now we've got a very easy way of actually duplicating with pig lenses human lenses in in order to study these things and there's lots of cool tests that have gone on and several other papers as Nick knows about that have come along I think it's a I think it's a great objectively look at some of these things for the first time ever so this is the results looking at ellipse FX that we had before and you can see that the two hour on that one and this is the human results were very very similar so a two hours going to be very close same thing with Ozil you can see there we are very very similar and this time we use exactly the same parameters we use the optimal parameters that we had discovered from the original test so we're trying to do what's the best of breed and then how well can we duplicate that with pig lenses but the more was done here also for the first time looked at longitudinal there's been a lot of studies have been out there that show that say torsional is better than longitudinal but what do they compare it to continuous longitudinal that's like saying I want to compare a nifty pistol I have with somebody else's pistol but instead of using their best pistol I'm going to use an old flint lock I mean longitudinal was shown a long time ago not to be the best way that you can deal with longitudinal that at least it would appear micro pulse these very short pulses may have some advantage nobody looked at it this is a very preliminary look more work has been more comprehensive but this is comparing 50% power to 25% power and then we use the same parameters that had been the best for Ozil and ellipse for those the best parameters for micro pulse don't know that work is now still ongoing but at least we're comparing the same thing and what you can see is on average at 0 1 in 2 hours very consistent results moving through here the harder they got that you certainly saw a larger difference between them and it was fairly it's not quite but almost twice as much so it appeared indeed that in regards to the overall time that 50% was a better way to go and and then we use that 50% on and said well let's compare it to Ozil IP and in spite of what people have said that is dramatically better it was actually not statistically better but it was actually shorter it was not too far off being statistically significant so this concept the longitudinal is old-fashioned and not nearly as good didn't bear up in this study and then compared to lips FX ellipse FX was a little better but again these were not statistically different so at least in the preliminary study best longitudinal does not appear to be worse than best of the other they appear to be very similar in their efficiency and as far as chatter is concerned they were all very minimal so the idea that one has a lot more chatter than the other did not pan out looking at these relatively hard chatter events were not statistically different and were very close to zero throughout so things get touted is better and nobody ever looks at it carefully I'm not sure if we were able to show that any of them using best scenarios were any different than each other but the beauty of this is now we have the ability to look at the Dewey tip and ask truly does it as a result of being protective the capsule does it result in less efficiency because now we can do a head-to-head comparison and these are the results as we went looking through this so this is out they put Alcon on here I need to get better slides on this but essentially this is Ozil IP and you can see that with a non-radius tip on average it was a second and that with the Dewey tip it was 1.8 second and that was statistically different so it took about 80% longer to remove a nuclear fragment with the Dewey tip than it did with a regular tip that's probably clinically important you know 80% longer this is for each time you're removing you know a certain size chunk of material but it would appear as though yes there is a distinct downside in association with use of Ozil it's probably clinically important so what about looking at the ellipse FX this this ellipsoid area looked at that did the comparison no difference in those you see the P I mean those are those are I mean you're talking less than 100 the second and everybody agrees they're not only not statistically different they're the same so interestingly a Dewey tip in regards to its overall motion for at least with an ellipsoid movement didn't appear to make any difference it was just as efficient now it's interesting to think about why that might be it's been surmised for a long period of time that because of the motion of Ozil where it subtends an arc that most of that overall cutting effect is a shaving effect and if you think about it that makes logical sense now if any of you have been involved who are woodworkers the rest you're trying to do shaving sharpness of your shaving tip is really important right you try and use a chisel if you want to do shaving that's rounded and dull all around the edge and you're gonna have a heck of a time doing any shaving so I think it makes logical sense that if shaving is a critical motion and you've rounded that edge cut off the sharpness you're gonna lose efficiency so it doesn't surprise me if indeed that is the main part of what the Ozil effect does that rounding that edge is less efficient now this ellipsoid motion there's a little difference in the cavitation that's probably gonna be created in association with that and there's a fair amount of longitudinal motion it appears as though shaving is not nearly as important and whatever there definitely there's the proof in the pudding right there those are not different those are exactly the same numbers so a dewy tip if you're going to be using ellipsoid type motion you can get at least a tenfold better protection of capsular breakage with no loss of efficiency that's clinically important right isn't the worst thing we run into is capsular breakage isn't that the biggest risk that we have if you cut that tenfold doing nothing else and not lose efficiency I think that's that's that's pretty important so what about looking at 612 micro pulse we do a six time micro pulse again exactly the same a suggesting that the longitudinal motion does not require a sharp edge those numbers again those those are not just not statistically them meaning they're the same as one that's about that's about as close as one as you can get those are exactly the same and therefore those who are using micro pulse or ultra pulse or a variation again the dewy tip does not result in any loss of efficiency whatsoever in the motion and association with that again I think interesting cool information to have potentially clinically important now it turns out that as we ran that batch and we looked at our overall times they were more on the soft side and we have found since we've now done a series of these that the amount of time of hardening very much depends upon the age of the pig lenses you get some pig lenses come in a batch are much much harder than others and neatly and therefore you need a little more time and so variation we do now as you get a batch you run it check about how long it's taking in a controlled way and then you may have to harden them a little more to get a consistent period of time that's more like your harder and this first batch we had was relatively short I said you know people are going to run the question we just ought to answer already let's make them harder and let's do a four what's like a four plus to a really brinescent cataract to see if this information holds because what I hear some people say with the dewy tip well I don't know if it and steve said this I like makes a difference until you get to a really hard nucleus and then I think the dewy tip is less efficient well guys we can answer this so let's go on let's get another run let's put this together so as you can see that these are harder because the amount of time remember we're down around a second now we've increased their hardness to their over two so these are roughly two times harder than what we've had in the initial set of experiments the results in regards to a torsional are exactly the same that's almost double so 80 to 90 percent longer statistically significant so indeed ozol seems to be very important that it has that sharp edge for the shaving effect and overall your efficiency is going to be about half of what it is take about twice as long to remove with ozol what happens when you go to lips FX those are again exactly the same see what your p-value is so confirmed it now time to removal here is actually about a little over twice as long and you can see that it does not make any difference and to complete the story six twelve milliseconds off on and frankly it was a bit leather radius was even a little last don't know what that's all about could just be sampling error those are not statistically different but again it only appears with ozol at a dewy tip results in less efficiency and it's roughly going to in about double your time for removal for the others there are exactly the same chatter I can tell you there was no difference in chat so you weren't getting an increase in chatter dewy tip doesn't seem to make any difference those were exactly the same for all of them only the efficiency was impacted so I hate the tip action is mentioned it's a shearing effect that longitudinal motion doesn't seem to need it and no difference in chatter is pointed out it is true that transversal in micro pulse have been shown by mark Schaefer an ultrasound engineer to induce more cavitational bubbles at lower energy so potentially cavitation is a more important factor and obviously the dewy tip doesn't appear to have any impact on that cavitational energy conclusions depending on if you're using ozol or not I think dewy tip is great I don't use ozol and I've gone to a dewy tip I think that if it's a if it's going to decrease my risk of caps that are breaking should I inadvertently contact the capsule tenfold with no other loss to me that's kind of a no-brainer so personally I thought dewy's come up with something fairly cool at least the way I'm doing it I don't see that I've lost any efficiency and this is what's fun about clinical research you know you can pose these questions you can sit and get some pretty definitive answers for the first time we're answering a whole series of questions both bryans are involved in this work we've done Jeff petty bill borla where's bill bill was over here he's been involved some of this and we're finding out what is the most efficient on and off time for longitudinal ultrasound and it's not exactly what a lot of people thought and we've got a paper that's just getting ready to be submitted and you know what what's the difference in regards to bore size and the overall size as far as efficiency it turns out it's not a linear relationship your your 20 gauge is far and away more efficient than 19 or 20 you know these are the kinds of questions that I think are going to be a lot of fun here as we move move on that's where clinical research I think really is couldn't be a joy and why I get as much kick out of it and getting these responses now as I did 30 years ago and so small change in the tip does it make a difference I think it does and I think it was actually clinically pretty important thank you very much questions yes Nick yeah I think Jeff what do we go get about 10 different studies lined up some more we just recently did and it's gonna be a lot of fun I'm just gonna have another example when Ozil first came out and I heard Dick McCool stand up and he said this modality a hundred percent protects against Wumber you put it a hundred percent power pedal to the metal the entire case you cannot get a Wumber and a lot of people took that up and I then I was hearing you know I got a wound burn and I'd never had a wound burn before and yet you were still hearing at the podium hundred percent you can't get a wound burn so we did it's a series of work but the most important is this this national survey in the United States in Canada and where we could get about a million cases and yeah there's always a bias in a survey but most people remember their wound burns pretty well net result is it turns out that Ozil was not protective against Wumber at all in fact it was right in the middle of the pack and it was it was probably better than continuous but that it was not statistically so in fact it turns out that power modulation wasn't important in prevention of wound burn far and away the biggest cause of wound burn was the use of Helan 5 and then it was how you how you use it if you're a divide-and-conquer surgeon you're much much more likely to get a wound burn than if you were a chop in that it was your approach it was important but the power that didn't know there was no protection for any of the different power modalities from Wumber so that's that's kind of fun stuff yes so I'm going to answer your question really really fast what you see here in a few things we put here is the only time this has ever been looked at by anybody and we're starting out with the very basics so anything that you talk about that that is slightly more esoteric exotic this the short answer is no and I'm not aware of anybody who's even trying to do any of this yet Nicky you get anything else other than our group I'm amazed at how many people who were willing to put their name and reputation who are almost like they're ignoring that this is getting objectively looked at at this particular time so the short answer is no but you know that that'll be 13 there you go we'll get Larry locks to make up some interesting tips and look at them but what we can answer those questions now so that that's that's going to be kind of cool all right thank you