 We'll get started if we don't mind. I have the pleasure of introducing our first speaker today, Neil Kalkar, who's joining us from the University of Arizona College of Medicine and one of the current ocular pathology and research fellows and his talk today is Enhancing the Rotational Stability of Toric IOLs and Black Avenue here. Thank you, everyone. Thank you, Mbarak, for your kind introduction. Good morning, and really thank you guys for giving me the opportunity to present today. This morning I'll be presenting on Enhancing the Rotational Stability of Toric IOLs in examination of two devices related to this issue. Before going into our presentation, I just wanted to show the general structure of the Mamless Wernher lab, where we focus on the analyses of IOLs used for cataract surgery. I also wanted to take a moment to thank Doctors Mamless and Wernher, as well as the other members listed here for their mentorship these past several months. Here are our financial disclosures. The first two grants are utilized to support the analyses of IOLs in our lab. While the last two are our research grants from two companies that make the devices I'll be discussing today. To start off our discussion this morning, I'll talk a little bit about why stability matters for Toric interocular lenses. For every one degree that a Toric IOL rotates from its intended axis, it decreases correction efficacy by about 3.3%. What this means is if a Toric interocular lens is off 30 degrees, it is effectively the same as putting in a spherical lens. And for patients with a higher cylindrical power, it has a larger effect on their overall vision outcome. And although 30 degrees is there now, when the first Toric lens was made, this degree rotation happened in about 20% of cases. Today, the incidence rate is a bit lower for, is a bit lower. And for 10 degrees of rotation, it's estimated to be anywhere from 2.8 to 6.7 degrees, depending on the type of IOL and the material used for the device. Most Toric IOLs that are placed are below this degree rotation, but at a retrospective study, I analyzed different Toric lenses and found that over 12,000 isotoric lenses would benefit from, 90% of these lenses would benefit from some degree of correction. And although then 90% would benefit from correction, only 1.1% of these are actually operated on. And this largely given the risk of surgeries, of surgery and the benefit the patient would get. And this really highlights the importance of getting the Toric IOL in the correct position in the primary cataract surgery. And there's several factors that contribute to the stability of Toric IOLs. And these include the axial length, the capsule of bag diameter, the capsule of Rex's size, and the IOL material or design. And clearly the last bullet is the easiest to modify. And that's where most of our effort goes to words. And there's several modifications that have been used to increase the stability. One is using an open loop instead of a plate. The other is the use of a hydrophobic acrylic, which is better than a hydrophilic acrylic, which is better than a silicone for stability. And lastly, there are specialized hapics that have been used such as using frosting material under the end of the haptics to kind of increase friction and stability. In trying to fix rotational stability, it's really important to consider when rotational stability occurs. Studies examining rotation found that most rotation occurs immediately postoperative to about three days post-op. And within that, the majority happens one hour after post-op to one day. And this is largely because in an outpatient setting, we have a patient lying in their bed. But after that one hour, we have them get up, be driven home, move around and come back. And that largely is where most of that movement occurs. And this is largely because as the caps are back, such as shrink after surgery, it's used the anterior and posterior capsule to the haptics kind of locking in that lens. When talking about rotational stability, it's also important to consider that 28% of measured rotation, intraocular rotation is actually performed from intraoperative misalignment. And this is largely due to removing things like OVD during cataract surgery. So I'd like to present two cadaveric eye studies done at our lab related to the subject of toric intraocular lens rotational stability. The overall methodology of these two studies is largely the same. Basically, we obtain cadaverized routine two 72 hours of nucleation, and the measurements are taken as above. And the eyes are prepared according to the Miyake apple technique. After measuring the capsule Rex's, capsule Rex's size and evacuating the bag, the test or control lenses placed within the eye and then assess for rotation and we assess clockwise and counterclockwise rotation with and without OVD. And the grading is graded by the operating surgeon who grades it one from very easy to four being very difficult. The first advice I'll talk about is a new mortar capsule attention ring specifically designed to enhance rotational stability of toric IOLs. And the results of the study were already published in JCRS. This device worked previous anecdotal evidence that suggested that capsule attention rings decrease toric IOLs. And in 2007, mortar released the Henderson capsule attention ring seen on the top left for improving the ease of removing cortical material. It was also noted to have an incidental decrease rotation of toric IOLs. And based on these observations, mortar released the Z-drill Henderson, see the bottom left there, capsule attention ring, which is a PMMA material with 16 indentations that are roughly the size of the terminal bulb of a haptic. So our lab performed the cadaver study to test the ease of rotation under three conditions, a toric IOL without a capsule attention ring. And this is using two different types of IOL toric IOLs, a toric IOL with the standard non-indented capsule attention ring, and the new toric IOL that has the sinusoidal pattern. And for the 10-nise we studied, rotational stability with the standard capsule attention ring was improved compared to the without capsule attention ring group. And it was even further improved with the new modified mortar capsule attention ring, suggesting that not only does the capsule attention ring increase stability, but also that the sinusoidal configuration improves rotational stability further. The second device I'll be talking about is the Staby lens intraocular lens. And this is an IOL platform that was specifically designed to be used for a toric lens. And this study has been recently published in JCRS for publication. So Staby lens to develop the IOL scene up here. This is a hydrophobic acrylic intraocular lens that has four haptics with a slight curvature to one another. And at the end of each haptics is a bulb to increase stability. When injecting this IOL, one of the trailing haptics are folded allowing the operating surgeon to correctly orient the IOL. So it's able to go on its intended axis before the haptic unfolds and locks into place. In this cadaver eye study, the lens is compared to a standard alkan toric lens, and it was statistically more difficult to rotate the test in all the conditions, both clockwise and counterclockwise with and without OVD. In addition, this IOL showed additional benefit. This test lens did not show any rotation when removing OVD, whereas the control lens showed both clockwise and counterclockwise rotation during the step of surgery. The test lens also showed quicker and more central correction after experimental tilt and desenturation. And this largely due to the fact that these four acute haptics kind of opposed one another. So, you know, counterforce. So previous studies have shown a need for increased stability for toric intraocular lenses to truly lock in the lens before the caps or bags able to shrink and adhere to the lens. Here we like to present two different Toric IOL devices aimed to address this issue. The first is a modified caps or tension ring that would aid in stabilizing any model of Toric IOL for rotational stability. And the second is a Toric intraocular lens with four haptics largely aimed to increase this issue as well. Lastly, I really do acknowledge the support of the people listed here for making this happen throughout their mentorship these past several months. And thank you for your time. I will now open the floor for any questions. I have a comment. No, no, you have a question. I was just going to say this week we've been talking a lot about Alan Crandall. It was the three-year anniversary of his passing on Monday. But actually the very last thing he ever said to me was in the OR, he was walking, he was like shuffling past me and was like, Oh, did you hear? We spoke all your Toric patients need to lay flat for the first 10 minutes and it reduces the incidence of postoperative rotation. And so that was like the last little bit of wisdom he ever gave me. And so I've been doing that for all my patients and I'm just curious if anyone else has incorporated that. And I honestly don't know if it helps or not, but so far I haven't had any. So I'm going to keep doing it. We're not going to have a lot of time for discussion and I apologize just because we do have a tight schedule, but that was based on a presentation that Alan heard. It's never been published. So, you know, hard to know. I don't, Alan told me this and it was a presentation and it was something that he heard. So I don't think we have any good data in regards to that at this point. So Nick's checking his head. Liliana is also looking at me. They know this literature better than I do. So, you know, it's interesting, but, you know, we don't know. The other thing I just want to point out that I apologize. I think we got to move on today is that you've always got to think about the law of unintended consequences. So I'm not saying the stable ones would have this problem. Whatever you put in the eye, you have to consider the possibility you have to take out. And so what might be different? I mean, those little bulbs, I could see potentially capsular movement around each of those where it and having rotational movement purposely is one way to help break some of those adhesions. This lens may be a lot harder to get out. So just remember, that's something that we learned a long time ago that, you know, it's one thing to put them in. You got to think about how you might have to take them out. And I apologize, I think we got to move on to our next speaker. Thank you, Neil, for that wonderful presentation. Our next speaker, I have the pleasure of introducing Kevin Eid, who is also one of the other acuapathology research fellows. You know, that's from the William Beaumont College of Medicine and the title of today's talk is titled A.S. CRS Toxicantere Second Syndrome Task Force Update. Thank you, Kevin. Thank you so much, Mabard, for the introduction and thank you for having me speak today. This is going to be a brief presentation on the A.S. CRS task force questionnaire. And this was started in 2007 by, or one and only, Dr. Mamelis as a way to combat a large task epidemic at the time. So this will be a presentation on the last 10 years of data. And again, this is our lab. And thank you, Dr. Mamelis and Warner, for the incredible mentorship. And these are the grants that help fund our research. I would just like to begin with a brief presentation on a case actually from a presentation that Dr. Allie Simpson gave earlier in the summer. This was here at the VA hospital. And this was discovered on the same day post-op for a run of the mill basic cataract surgery. So as you can see, this is one hour after surgery and there is a significant amount of fiber information and inflammation. And it was presumed to be tasked due to the cuteness and eventually was confirmed to be tasked. But what is task? So task is toxic anterior segment syndrome. And it is a sterile inflammation of the anterior segment secondary to any kind of anterior segment surgery. And it is an inflammatory cascade that is triggered by a toxic stimulus that could cause corneal endothelial toxicity. And the big thing with task is that it is very acute. It could happen right after surgery. It could happen the next day. But that is one of the hallmarks of it. And in clinical presentation, corneal edema is usually a big symptom, as you can see in this picture, followed by sometimes you can get hypopian formation or even iris atrophy. And the big thing with task is to rule out infectious endoplamitis. So the big thing to do is to have a negative culture because task is sterile inflammation. And there are some clinical features of tasks that are, I guess, you know, unique from endoplamitis, of which is the presentation. It could be a little bit more acute, the corneal edema. And then for endoplamitis, it usually has a more severe, sinister anterior segment inflammation. The question is what causes tasks? And the unfortunate answer is that lots of things do. So one of those big things to break it down is endotoxins that are on or in surgical equipment from improper cleaning, getting introduced into the eye, causing an inflammatory cascade, certain substances that are introduced into the eye, whether the pH is too low or if there's detergents or if there's an overdose of a specific pharmaceutical that can cause it, enzymatic detergents that cannot be deactivated and autoclave can cause it. So there's lots of things that can cause tasks. And I wouldn't be a pathology fellow if I didn't sneak in a picture of a pathology slide. And this is a H&E stain of a corneal button from a patient with tasks. And as you can see, there's a complete dearth of endothelial cells and a vagination here in the decimates membrane in the stroma. So the big thing with tasks is that you see significant, you know, there's lots of causes that can cause tasks. And that makes figuring out what is causing the actual outbreak pretty difficult. And this is from Dr. Ali Simpson's presentation where she had to look for, you know, basically everything in the OR just to account for it and see if it's a cause of tasks. And it's a challenge because it is, there's so many variables, but that is where the task force survey comes into place. It asks specific questions about cleaning practices and products that are used to help streamline the process and allow a easier search process and what can cause tasks in the facility. And here are some of the questions that are asked. So looking at cleaning practices, what cleaning products are used, if things are being reused or not, and the type of substances injected into a camera. So off this research or off these questionnaires, there's been two publications from our lab looking at this data, the first of which look at the first two years of data and color pack at all. And then the next one is the next three years of data in Bodner at all. And as you can see, there's a significant amount of cases of tasks looked at in these studies, which just shows just how big a big deal it was. Or is. And it was found that the common practices or common causes of tasks were inadequate flushing of handpieces, enzymatic cleaners, and using certain substances at wrong concentrations. So my research builds off of this and is a direct comparison to those that year between 2007-2012. So I'm looking at 2012-2022. And as you can see, there's no significantly less task cases. So over 500 cases in 56,000 cataract surgeries in this time span. These are the amount of reports that we get per year. There's like a median of around five. And here's the geographic breakdown. So as you can see, it's pretty equally distributed across the U.S. with the inclusion of a good chunk of international facilities submitting reports. And here are the key findings. And these are basically what we wanted to see. So there's a significant decrease in the task cases, a decreased tenfold. We see 53 cases per year compared to the over 450 cases over a decade ago. And then in terms of core cleaning practices and improper use of different products, we see decreases of those reported incidences across the board, which is a good thing. In addition, we do see an increase in the use of intracameral antibiotics, which might be a good thing, suggesting that it is a safe practice after some of the kings have been ironed out. There's some issues early on with the formulations of antibiotics. So the increased use of proper antibiotics and not seeing a huge spike in tasks might be suggestive of a good thing. And in addition, there's some practices that are nearly abolished, for example, the use of tap water to flush out a handpiece, which sounds obvious. So here is a visualization of this data. And again, this is comparing 2012 to 22 to the five years prior to that. And for flush volume of handpieces, this is less than like improper flush practice. So you should be doing 120cc or higher. And as you can see, there's a huge decrease in the reported incidents of that. Same thing with occluded IA tips, reusing the fake o tubing, reusing of cannulas and other tips. This is the tap water for flushing out the handpieces. So huge decrease, but the practice is rarely done anymore. And the use of enzymatic cleaners. So we do see a big decrease. And it's still kind of surprising that it's at 40%. But this is one of the big things that Dr. Mammals and the task force have been trying to minimize. And it's good to see that it's heading in the right direction. So same thing with the use of ultrasound baths. There's a slight decrease, but the proper practices of cleaning ultrasound baths have increased. And same thing with the ophthalmic instruments not being cleaned separately. There's a big decrease in that. In terms of reported product practices. So the use of antibiotics being added to BSS, there's a pretty big decrease in that. As mentioned earlier, the use of intracameral antibiotics after surgery has increased. And the use of intracameral anesthetics hasn't really changed much. However, there has been a positive change in the type of intracameral anesthetics used. So huge jump in the amount of preservative free anesthetics used, which is exactly what we want to see. And likewise, the type of anesthetics used, we want to see 1% lidocaine because that has proven to be safe. So only 11% use 2% lidocaine, which is too high of a concentration. So it's a small minority. To summarize, here are the key points. Cases of tasks are decreasing, which is exactly what you want to see because that's the whole point of the ASERS task force. Poor cleaning remains the largest potential contributor to tasks. And we see that even though this exists, we see huge decrease in poor cleaning practices compared to the earlier time frame. And then intracameral antibiotics and anesthetics use have become safer, which early on was a challenge in trying to minimize tasks. And just to add, this is the guidelines for proper cleaning of tasks. And it's a great thing and it shows exactly what you're supposed to do, but it doesn't eliminate tasks. And that's something we've noticed. There's so many variables in the OR that it's hard to control everything. Task could happen to anyone, even Dr. Mamelis. And this is why I'd like to end with a quote that I think summarizes tasks pretty well. So everyone has a plan until they get punched in the mouth. And here are my acknowledgments. Thank you so much for the help. And I'll be, these are my references, and open the floor for any questions. So I know we had a tight schedule here today. And I apologize. I will say one thing here. Nick and Liliana can smile about this one. We're only one stupid manufacturer's mistake away from a whole onslaught of tasks. So never forget that. And he and I have both had calls from former colleagues. One I remember had done 14 cataract surgeries. Every one was hand motions or worse with horrible tasks. Every one. So this is one that can bite you rapidly. And you need to be prepared to know how to deal with it. All right. So it's a real pleasure to have Dr. Pitha here with us. I could spend a long time talking about his credentials and background, but I'm not going to. You know why? You want to hear from him. You don't want to hear from me. So Dr. Pitha comes to us from Johns Hopkins, from Wilmer. He has, we forgot to put his PhD up there. Sorry about that. But he has both of those from Dartmouth. And he is a clinical involved as a glaucoma specialist. But on his research side, he's very interested in both wound healing and also developing of new MIGs devices. And so with that, I bring you Dr. Pitha. Let's give him a big Moran. You're welcome. Well, thank you for that very kind introduction. And thanks for the opportunity to speak to you today. I'd like to thank Susan Brown, who's really been a great point person on kind of arranging everything. It's made it really kind of go very smoothly. So I'm going to, I'm a clinician scientist at Wilmer. I spend about 50% of my time in clinic and in the OR and 50% in lab. And one of my research interests is in improving glaucoma surgery. I also work on drug delivery and glaucoma and I have some projects on neuro protection, but I'm going to talk about two projects on improving glaucoma surgery today. So these are my disclosures and I will list the funding sources at the end in the acknowledgments. So I'd like to start this presentation with a case presentation. So this is a patient who I think illustrates the need for glaucoma surgery improvements quite well. So I saw a 67 year old African American man with advanced primary open angle glaucoma several years ago. He was referred from an outside provider with gradual visual dimming in his right eye. So he had a history of having a CRVO in his left eye and was NLP in that eye. And several years prior to my seeing him, he had had an abac internal zen place that had worked well for a while. It had met its target of about 14 millimeters mercury and his maximum pressure over the course of his glaucoma was about 30. Another important thing to note in this patient is that he lived about three hours from clinic. So it was really difficult for him to come and see me regularly. So this was his exam when I first saw him. Vision was 2030 in that eye. Pressure was about 27. And over that zen implant, he had kind of a very nice bled that looked very ischemic. So the tissue was very thin there. And his cup to this was 0.95 maculose flat. He does have diabetes, but no significant diabetic eye disease. And this is what his 10-2 visual field looked like back then. Quite advanced, but his central vision was very nicely preserved. And then this is the last four years of his life in my clinic. So I first initially tried to revive his zen by doing a needling, which didn't work. So we placed a super temporal Ahmed, which worked very briefly, but then failed rapidly. So he required some diamox, which he didn't really tolerate well. I placed a second zen, which worked really well until the tip was excluded by Iris in the anterior chamber, but our fellow did a laser to un-occlude it. And then we ran across this really nice period of a couple years where his pressure was under good control. And he was very happy. Zen generally started to fail. So I had to add meds. He really developed a lot of medication intolerance. So I tried to reduce his medications by doing a micro pulse CPC, which didn't work really at all. So after a lot of discussion, we decided to put an infra nasal Ahmed in this patient, which has worked well, but has led to some corneal edema in him. So now not only do I follow him, but he's also followed by cornea, who's holding on doing anything right now. And this is what he looks like now. His 10-2 has advanced. His vision is worse, most likely because of the corneal issues. But I really like this case because it's an illustrative case of glaucoma care. And there's a lot to unpack in it. But today, I'd like to focus on what this case tells us about glaucoma surgery. So we could discuss the decisions that were made along each step of this patient's case. And we could do that for a long time. But I don't think there's really any question that for patients like this, there's a need for improved surgical options. And when I say patients like this, I'm talking about patients who have disease that could really lead to irreversible blindness. So the primary option for patients in this situation has traditionally been filtering surgeries, which can lead to effective and sustained IOP reduction. But they come with significant limitations. And we know a lot of these. A post-operative hypotony always is in our mind. And there's really a long recovery time for a lot of these surgeries in our patients. Over the long term, a lot of these surgeries fail due to fibrosis, so around the filtering lab or around the plate. So we might get this great period where the patient's really well managed. But over a time, surgery, fibrosis, and IOP, again, elevates to unsafe levels and disease can progress. So minimally invasive glaucoma surgeries like the hydrostent, the istent, and the Zangelstent have brought novel device designs and novel materials to glaucoma surgery. And they've also reduced the risk profile compared to standard filtering surgeries. And the recovery period for these surgeries is significantly better than a lot of our filtering surgeries. But they come at a cost, right? So these surgeries traditionally have less IOP reduction. And they weren't really developed to target those at greatest risk of vision loss from glaucoma. So there's a trade-off between safety and efficacy in glaucoma surgery. And I think this quote from Dr. Getty's review really nicely summarizes this trade-off that really benefits those who have early to moderate glaucoma and who are not candidates for some of our safer and who are candidates for some of our safer and less effective surgeries. So these types of surgeries really disproportionately benefit those at lower risk of blindness from glaucoma. But at the same time, it places a really disproportionate burden of complications and failure on our patients who are at the highest risk of vision loss. And this burden is even greater for patients with advanced disease who have to travel significant distances for glaucoma care, either in rural areas or internationally. So if we had a wish list for an ideal glaucoma surgery, I think we could all agree that it should be durable, offer significant IOP reduction, and have a good safety profile. And there are a number of other additional features that would be great as well. And they're listed at the bottom of this slide, which brings me to two projects that I've participated in to try to improve glaucoma surgery with these goals in mind. The first project is a collaboration with colleagues at the Whiting School of Engineering and the Applied Physics Lab, where we're trying to design, and it's all solely preclinical, where we're trying to design filtering surgeries using technique called electrospinning. The second project was a collaboration with war and associates. So it was an industry collaboration. And our goal was to utilize vortex and glaucoma implants. And it's gone from concept to almost first in human over the past five to six years. We're kind of right at that verge of getting our first patients with this implant. But I'm going to start with this electrospinning project. The first device we decided to create was a filtering tube that we called the pressure control shunt or PCS for short. And the principle behind the shunt was really pretty simple. We based this design on the Hagen-Purcell equation with a modification in which we incorporated a biodegradable sacrificial inner sleeve within the shunt. And the purpose of this inner sleeve was to prevent hypotony in the early post-operative period by creating a small diameter lumen. And as the sleeve degraded, the lumen then expanded and allowed further IOP reduction once it was safe to the natural post-operative healing process. It takes several weeks to months after glaucoma surgery. So the thought was that this feature would provide a really soft landing of IOP reduction after the early post-operative period. So we made the implant. These were the dimensions of the implant. You can see the lumen is about 75 microns before the inner sacrificial sleeve degraded and then expanded to 100 microns. This is what the stent looked like with its inner template wire on the inside and figure B there. And that's what it looked like next door quarter. So it's a very small stent that could be placed in the anterior chamber and drain into the subconjunctival space. And we showed in normative rabbit eyes that the sleeve blunted the early post-operative IOP reduction compared to shunts without the short sleeve that's on the left side of the screen. And it also led to a gradual increasing reduction of IOP over about 28 days, which is the time force of that inner sleeve degradation. But when we looked at the histology of these shunts, we saw something that we thought was pretty interesting. Cells were incorporated into the wall of the shot, but there was otherwise not a lot of fibrosis that we saw. In fact, it's not shown in this slide, but we saw more fibrosis around the nylon sutures that we used to close our suture than we did around the implant itself. And cell incorporation wasn't really a surprise for us because we use a fabrication technique in making these stents called electrospinning. So electrospinning is a very well-established technique in which a polymer is sprayed out of a syringe across a voltage difference onto a template. And the template is then covered in these micro or nanofibers of your polymer that solidify. And it's a really well-established technique in fabricating medical devices, and it's really tunable and modifiable across a wide variety of polymers. So when we make our shunts, we basically spin around a template wire that's attached to a chuck, a rotating chuck. The interior diameter of this shunt is then defined by the diameter of the template wire. And the thickness of the shunt is defined by the duration of our electrospinning session. But before we move on, let's talk about a little bit about what drives fibrosis in filtering glaucoma surgeries. We know a lot of these drivers of fibrosis, and there are probably multiple different ones. Bleb and capsule geometry, drive fibrosis, the tissue quality, and inflammatory mediators in the anterior chamber. And I'm going to talk a little bit more about this later, but fluid challenge and wall tension within our bleb also probably drives fibrosis. And we battle this in a number of different ways. Primarily pharmacologically, right? We use antifibrotics at the time of surgery. We use steroids after surgery to control fibrosis. We also try to control our bleb and capsule geometry and control our tissue quality maybe by stopping eye drops before we have the surgery. And we also try to be meticulous in our surgery. We try not to create a lot of damage to the tissue when we're doing our surgery. But today I'm going to talk about changing material of our implants. So we know so much more about fibrosis than we did 10 or 20 years ago. We know that there are molecular signals that drive fibrosis, and we know the different cell types that are involved, as well as the role of mechanical features in driving fibrosis. So we were discussing these results with a graduate student who had been involved with the PCS, and he decided to test the hypothesis that a specific feature of our implant was responsible for its favorable fibrotic profile. So his hypothesis is outlined in this slide. He basically thought the topography of our electrospond shunt mimicked the natural cell environment and therefore maintained fibroblasts in a dormant state. He hypothesized that if we made the same shunt with a smooth exterior, then its antifibrotic effect would disappear. So the first thing we did was characterize our surfaces. To do this, we mainly used atomic force microscopy. This basically showed that our smooth shunts were smooth, and the outer surface of our electrospond shunts had a nice topography on the micron scale. We also showed that these nanofibre surfaces were a little softer than smooth surfaces, which is shown in the Young's modulus there. And then the first thing we did was we looked at these surfaces in vitro. We took fibroblasts and cultured them on these surfaces, and the first thing we did was look at cell morphology. What we saw that the cells on the electrospond surfaces integrated within the electrospond fibers, you can see that on the other slides there. They also had fewer stress fibers and were generally smaller and less proliferative than cells on the smooth surfaces. So they looked dormant. The next thing we did was we looked at markers of myofibroblast differentiation. Now myofibroblasts are the fibroblasts that are thought to drive fibrosis. So here we look for one marker of myofibroblast called alpha smooth muscle actin and working at transcription of that gene. So what we found was that cells cultured on the nanofibre surfaces exhibited reduced SMA expression than those on the smooth surfaces. And the really the most interesting finding, I think, was that when we treated the cells with profibrotic agents like TGF beta or LPA, the nanofibre still inhibited SMA transcription compared to smooth surfaces. So the level of inhibition that we saw was on par with a lot of pharmacologically active antifibrotic agents that we use in the clinic and that we're trying to develop in the lab. And just to point out that the y-axis here is on a logarithmic cell. So the amount of reduction we saw was actually fairly dramatic. But the hypothesis really was that these nanofibre surfaces would improve in vivo activity. So we took this to rabbit eyes. We fabricated two different shots. One was a PCS with a smooth exterior. The other was a PCS with an outer nanofibre exterior that surrounded an inner impermeable layer that would exclude cells from the inner lumen. So we implanted these shots in rabbit eyes. We measured serial IOP. We performed clinical exams to look at bleb morphology. We established whether the shots were patent by anterior chamber fluorescein irrigation and eventually were performed histologic exams at these device blebs. I'm going to skip over a lot of that analysis. But basically what we found was that the blebs around the nanofiber shots had this very nice thin external outer capsule and a healthy edematous appearance. They also had very low SMA expression. The blebs around the smooth shots on the other hand had thick organized capsules and high SMA expression. It's pretty well established that a thick capsule is generally impermeable to fluid and associated with surgical failure. So this really led us to think that the blebs around our nanosurface shots had a much more favorable appearance than the smooth shots. IOP data in these studies was a little bit messy. And the main reason it was messy is because these smooth shots actually migrated within their entry tracks. And there was significant peritubular flow around the tube. So fluid wasn't going through the tube, it was going around the tubes in the tract. And you can see a picture here of eyes taken at four weeks that show almost complete migration of the smooth shot into the anterior chamber, pointed out by an arrow there with very stable localization of the nanoshunt. This migration was fairly common in the smooth shots and did not occur at all in the nanofiber shots. So then we compared our nanofiber shunt to some clinically used materials, including the Zen gel stent and the silicon tube from a Bearville. And we basically did the same experiment as before. But this time we got cleaner IOP data and we can just walk through this here. So the silicon tube, which has a very large inner lumen caused early hypotony with an IOP trending upwards at about 20 days. And that's the BGI tube there. The Zen implant mitigated this early hypotony. And you can see that in the green triangles there. And the PCS nano, which is the name of our shunt, mitigated this early hypotony and additionally led to a gradual IOP reduction over 28 days. Again, we looked at histology in these slides. And when we looked at the BLEB capsules again and again, well, we saw much thinner capsules around the nanofiber shunts than the Zen or the silicon tube. So again, more favorable fibrotic profile than in the Zen or the silicon tube. And the last thing we did here was we looked at gene transcription and the BLEB tissue from each of these implants. And we found that the nanofiber surface had a significant anti-fibrotic and anti-inflammatory activity. So our thoughts here, these are really working on a molecular level. And this is occurring at least over 28 days here. But 28 days is a pretty short period of time. In rabbit models, 28 days is certainly enough to see a pretty dramatic failure of your glaucoma surgeries. But we wanted to look at longer periods of time. So we looked at their performance over 90 days. And the PCS nano again, it was biocompatible and well tolerated. It provided or created a capsule that was ademinis with a very thin outer capsule and had a very favorable profile in terms of its histologic appearance and biocompatibility. We also, you know, due to COVID, we had this one rabbit that had one of these in for about a year. And we took out the PCS nano afterwards and were able to verify that it really maintains its nanotopography over a long period of time. So a very nice stable appearance of its nanotopography. So in summary of this project, the PCS nano design allows immediate and progressive IOP reduction in the post-op period. And it prevents early hypotony. The nanofiber's topography reduces basal and induced transcription of fibrosis markers. And the thought is that, you know, this signal is consistently there as long as the device is going to be there as opposed to a pharmacologic agent, which is only there temporarily, even under sustained release conditions. It produces thinner and histologically better capsules in vivo and reduces the likelihood of shunt migration, which is a little bit of a surprise to us. And it also reduces transcription of fibrotic and inflammatory transcripts compared to some currently used devices. And it's biocompatible over 90 days, and it retrains its structure for more than a year. So our conclusion from these studies is that it's possible to obtain sustained non-pharmacologic antifibrotic activity by modifying implant topography. And, you know, we hope that this activity could produce improved clinical GDI performance. We're continuing these studies and looking at different modifications of the topography to really try to tease out which ones have the highest antifibrotic activity. So we can test those in pre-quantum models as well. So I'm going to move on to the next part of this presentation. So the next part of this presentation was a collaboration with the Gorin Associates maker of Gore-Tex, which is EPTFE, is the name of the polymer. And it's an extremely biostable material used in many, many applications, but most importantly in many biomedical implants. And a lot of vascular grafts it's used also in repairing hernias and a number of other features. So they're interested in expanding the use of Gore-Tex and biomedical implants. And it has this really interesting structure composed of nodes and fibrils shown here on FES under transmission electron microscopy that allows cellular integration and the nature of this structure again, just like electrospraying is highly tunable. So they can modify the microstructure and the nanostructure of Gore-Tex to really meet specific needs with different biomedical implants and the needs of the different surgeries that they're involved with. So the hypothesis that we are addressing here was that EPTFE would allow cell integration and therefore create a porous blood after glaucoma surgery as opposed to a blood that didn't allow fluid to run through it. And this hypothesis was really supported by some previous work for the potential of EPTFE and glaucoma surgery. And this was noted as early as 1991 when it was noted that the tissue surrounding EPTFE implants created a better-looking tissue after filtering surgery in animal models. And there have been various attempts to kind of incorporate EPTFE into biomedical implants, but this was really the first one undertaken by porous glaucoma undertaken by Gore-Tex who are really kind of the leading manufacturers and experts in this material. So we started off with a proof of concept experiment. So our collaborators at Gore created two tube implants for a rabbit model. One was fabricated from silicon and it basically looked like a tube there and the other was fabricated from EPTFE. They were identical except for the materials that they were made from. And this is what they looked like, right? So the silicon looked like a tube, just smaller. And when we placed them in rabbit eyes, you can see the outline of it underneath the subconjunct tidal space. Because of the rabbit eye anatomy, you can't really place it too far behind the limbis. So they were pretty much adjacent to the limbis and the tube went into the anterior chamber. The EPTFE implant shown here placed in rabbit eye and we actually outlined the outer edge of it with a black marker with a Sharpie was basically a little balloon at the end of the tube that would inflate when aqueous humor flowed through it. And there was a kind of very specific design to this EPTFE in that it was dual layered. And it had an outer layer that allowed cell incorporation with the fibrils and nodes. But then it had an inner tight layer that excluded cells. It still allowed fluid to run through it, but excluded cells. So you had this little balloon that would inflate with aqueous humor. Cells can incorporate into the outer layer of it, not get through into the internal part of the balloon, but fluid could percolate out of that balloon. And the hypothesis was that this would create a thin capsule and the tissue around it would be permeable to fluid because the cells were incorporated there. So when we looked at histology, we saw cell integration and a thinner capsule. So capsules, you know, went from about 150, 200 microns to less than 50 microns surrounding these silicon implants. And this was seen out to three months. So in this slide, the control is the silicon implant and the high is actually the Gore-Tex implant. We tried multiple different Gore-Tex implants. I'm not going to go into that, but the high was the one that we used in our three-month studies. And one thing we really couldn't explain, which was a little bit of a mystery, was when we were planning these experiments, I did expect the capsule around the silicon implants to be more like 350 or 300 microns thick. So they were a little thicker, thinner than we thought they would be. And we were kind of scratching our heads with this because we were really reassured with the thinness of the capsule around the Gore-Tex implant, but we really couldn't explain why our silicon implants did so well. So looking into this question further, we came across the work of Wilcox and colleagues on blood geometry and its relation to capsule thickness. And what they basically found in the late 90s and early 2000s was that in animal models, the capsular thickness was directly proportional to the radius of curvature of the plate in these implants. And you can see that here. You can see the larger bare belt implants are associated with a thicker capsule, whereas the thinner or the smaller implants were associated with a much thinner capsule. And this is across multiple different animal models. So the theory was that a larger radius of curvature led to more wall tension within the blood because of Pascal's law. And that led to a stronger fibrotic drive and a thicker capsule to accommodate for that wall tension. And you had this tradeoff between the surface area of your bleb and the thickness of the capsule that you really couldn't avoid in this. And I really think this graph is pretty beautiful because the r squared on it is 0.95, it's across multiple different models. And it really shows the relation of the plate radius of curvature and the capsular thickness being pretty remarkably stable there. So the important finding of this study was that the EPTFE devices formed thinner blebs than the silicon controls. In other words, the EPTFE we thought successfully decoupled the capsular thickness to the geometry relationship that we saw here. So here I've zoomed into the lower portion of the relationship developed by Wilcox. And I'm going to plot our average results here, show up. And as you can see, the capsule over our silicon controls was actually pretty well predicted by this relationship while the EPTFE took the capsule off this curve. So this suggests that for the same device size and in the presence of aqueous flow and wall tension, the EPTFE prototypes do not incite the same magnitude of scarring response. In fact, the collagen lead down is about five times less thick than that of the control. So we were pretty excited about this result and we presented this to our advisory council and they said, you know, you guys are talking a lot about capsular thickness, but what we really want to know is whether that capsule is permeable to fluid. So this was a little bit of a technical challenge, but our engineers at Gore, guided by techniques described by Krausden and Coot in Australia in the early 2000 set up a syringe pump and it had an inline manameter that could be connected to a 27 gauge needle. And we would make a shelved needle track through the cornea and we cannulate the internal tube after the device had been in for several months. And what we could do was we could infuse diluted fluorescein into the blabs and fix pressures at which we escalated stepwise and we could measure the resistance to fluid outflow. And another thing that we did was we would infuse fluorescein to create a pressure and then stop infusion and look at what the pressure did over time. And you're going to see some of those results here. So in the photos on the right here, you can see our silicon implants. And the first thing I'd like to point out to you is the floor scene here. It doesn't extend beyond the borders of our plate and it basically stays within the confines of the capsular geometry. And when we did this experiment where we were infusing and we pressurized that blab and then we stopped infusing, you can see that the silicon implants really maintained their pressure pretty well. So if you inflate a galvanized rubber tire with error or with something, it's going to maintain its pressure because it's impermeable. But in contrast, when we did this with our E-P-T-F-E implants, what we saw, I'll point to you first to the fluorescein here pictures, is that the fluorescein extended beyond the borders of the actual implant. So the borders of the implant are outlined in a hatched line there. And you can see the fluorescein extends beyond that. And then when we did this experiment where we infused, pressurized the blab and then turned off the effusion, you can see that the pressure within that blab actually decreased fairly rapidly in contrast to the silicon, which suggests to us that this is a permeable tissue that's being created as opposed to the silicon implants. So in conclusion, from this part of the study, this is a novel GDI. It's made of E-P-T-F-E, and it's a special dual-layered E-P-T-F-E that creates a permeable thin capsule. And we're excited that it decouples the exposure of aqueous humor and the plate radius from the capsular thickness in our rabbit model, which is really prone to scarring. So early feasibility studies in humans are underway. I don't think we've enrolled our first patient, but that's certainly happening. And we've of course redesigned this implant for use in humans rather than in rabbits. So I'd like to make separate acknowledgments for the two parts of this presentation. The first is for the electrospinning. These are my collaborators. Aditya Josiel was the grad student who did a lot of the legwork on this and actually came up with that hypothesis as part of his graduate thesis. I collaborate closely with Dr. Kunal Parikh, who is a biomedical engineer and actually started off as a graduate student as well in the labs of Dr. Justin Haynes and Laura Insen, who are my close collaborators within the Center for Nanomedicine. I'd like to acknowledge my lab members who've helped on this and our funding sources for this project. And then I'd like to thank my colleagues from Gore. These are kind of the main people who I've worked with from Gore, Peter Rober, Jeff Taller, Kevin Savery, and Jeff Fine. My co-PI on a lot of these studies or a lot of this work was Amanda Bickett, who was at Hopkins at the time. And we did a lot of this work together in the wet lab and with our animals. These are the lab members who helped on this. And I'd like to thank my advisory council who gave a lot of really great input on experiments to do. It was like having a thesis committee when I was mature enough to actually kind of listen to them and take that wisdom in. So I appreciate that. I'd like to thank you for your attention. I'm really happy to take any questions. Thanks for having me. So that's pretty fascinating. I've had a chance to talk to some of the Gore people. I know they're very excited about this work, but it shows that we've often thought that an extremely ultramicroscopically smooth overall surface was probably the best way to not induce any issues or problems. And yet increasingly in other areas as well, they're showing, no, if you can get tissue incorporation to where the tissue, I almost think of it in a simple way that they just think this is normal, then it doesn't elucidate a lot of these, the different scarring mechanisms and the rest. And probably the reason it's not slipping, it's actually incorporated into the tissue. Therefore, there aren't really minimal or no forces. And if they were to be there, literally, it's kind of grown in as part of the tissue. I think this is fascinating. I'm really excited for the clinical trials. Yeah, no, I'm excited too. So, you know, it probably works on two different levels, right? So with that balloon having tissue incorporated probably takes away some of that wall tension, right? Because the tension in the blood capsule is shared between the tissue and the actual implant itself. So the cells are probably exposed to less tension and have less of a fibrotic mechanical driver there. But, you know, there's also evidence that we saw from that first project that just topography cells kind of sitting in the right region really influences a lot. And you see that a lot. Like, you see that, if you take young cells and put them on an old tissue, they start acting like old cells. And if you take old cells and putting on young tissue, they kind of revert to a different phenotype. So I think this is something we can definitely take advantage of in Gulfoma surgery. Thanks. Yes. I'm impressed that you are able to use both the nanotechnology and the Gore-Tex in a rabbit model for a long period of time, because we work with Alan Crandall. Many times over the years and pretty much anything we did would completely fail in four weeks in a rabbit. And so I'm impressed that both of these technologies will keep the bleb going and really limit the fibrotic reaction that you get in the animal model. Yeah. So rabbits fibrose dramatically, right? And the Gore-Tex was all done in the absence of mitomycin C. And we really didn't power any of those studies to look at pressure. And we weren't expecting to see pressure reduction because they fail so rapidly. So that's why we looked at bleb thickness and permeability. And I wasn't showing any pressure data there because we really didn't empower the studies for that. And because of my experience with it before, I really wasn't expecting IOP reduction. The PCS studies were done in the presence of mitomycin, which allows the surgeries to go last further. And it's been shown even with the zen gel stand. If you want to study that in a rabbit model, in the absence of mitomycin C, it's completely useless. Yeah. Yeah. And thank you so much for your great presentation. I wanted to build up a little bit more on our earlier discussions about animal models for glaucoma. And you showed two interesting studies where it seems the rabbit's a reliable model for tubes. But as you know, there is so much interest in meek devices. So could you elaborate on your thoughts for the rabbit model as a meek device evaluator for efficacy and or biocompatibility? Yeah. So I think in terms of the rabbit eye, right, they don't really have a schlem's canal in there. They have these trabecular beams. So their trabecular mesh work looks completely different. So I think a lot of animal or angle surgery efficacy studies are kind of off the table, I think, in the rabbit. Biocompatibility, you know, the rabbit eye is such a great model for biocompatibility and so much work has been done on it. And we have so many kind of standardized ways to kind of evaluate it. I think it's still, you know, possible to do biocompatibility studies in that. But yeah, I know I wrestle with this a lot because, you know, as we were discussing, for a lot of the meeks devices, especially if you're evaluating something like an angle procedure, the best model is the human eye. So you're doing cataviric studies on the bench, which is an ideal because those are a limited time period. So you don't get an idea of fibrosis or kind of how the tissue reaction to those devices affects efficacy. So, you know, I don't know, we could try higher animal models, primates, pigs, dogs, to evaluate that. But, you know, I think there would be a lot of method development in that, which could be really valuable because right now, you know, we're evaluating them, establishing biocompatibility, evaluating them on the bench top, and then putting them on in human eyes, where we can't really follow the tissue reaction to them. Yes. One of the side benefits of this biomedicine is with glaucoma devices is we get to deal with the misaligned eyes and disabling diplopia that result. And I'm struck, if you could decrease inflammation, that may significantly improve some of the restrictive strabismus. It isn't just from the mechanical effect of having that large form body in the orbit. And so that's one thing, as you move into humans, I'd urge you to have, you know, one of my counterparts at Hopkins look at the effect on alignment compared to standard devices. My suspicion is you may see a significant difference, and it also may prove to be easier when we have to go in and operate in tap dance around the capsule to get in and get things taken care of. This is exciting. Good presentation. So you think, sorry, you're saying that misalignment is also caused by inflammation independent of the mass effect? I think it is. And often the case is either malposition of the plate or inflammation. And with the supratemporal valve, you're talking about abnormal attachments to lateral rectus and the suprarectus keeping in mind now that the muscle pulley mechanism, you know, that whole anatomy is much more complicated than we're all led to believe when we learned about it as resonance. And so the impact that has may be, you know, have a significant impact on the alignment and the ability to put these things in and not have the patients say, yes, you saved my vision doctor, but now I need to figure out which pedestrian to miss. You know, it's, it would be a good thing. So I think your presentation is wonderful. This is exciting work. Thanks. All right. I think we're out of time. If anyone wants to, you know, this is simulated, everybody's interesting glaucoma, the best specialty. So Dr. Pitha is speaking this weekend at IGC and you can come crash and learn all about glaucoma there as well. But thank you all for attending.