 Good morning, everyone. Good morning. So I'll get started. So for those who don't know me, my name is Katie Wing. I'm one of the cornea fellows. And today I wanted to present about the surgical management of peripheral ulcerative keratitis. And I should clarify that actually, we try to avoid surgery as much as possible in these cases. But I wanted to talk about situations in which you may not be able to do that. So let's go to the case that prompted this thought process. We had a 30-year-old African-American male who presented to our clinic in April of 2018 with discomfort in the right eye for two weeks. This is a photo of his eye, of his right eye. His vision was actually 2020, and his pressure was normal. But as you can see here, he had conjunctival and scleral injection leading up to the limbis, an area of peripheral crescentic ulceration that also had an epithelial defect overlying and stained with fluorescein. So he clearly does have PUK. Now, why does he have this condition? We actually performed a full workup. And his review systems was negative. We sent laboratory testing, which was negative for ANA, rheumatoid factor, ANCA, infectious conditions such as quantifera intreponemal testing, sarcoidosis. And we actually eventually did also perform swabs of the area of ulceration that were negative for HSV, VZV, PCR, and bacteria. His chest X-ray was negative. No high-lart lymphadenopathy to suggest sarcoidosis. And we unfortunately were not able to obtain a family history as he was adopted. But ultimately, it seems like this is probably an undifferentiated case of PUK, so not related to a systemic inflammatory condition, but clearly still vision-threatening. So he was actually lost a follow-up for a few months after this point. He came from Wyoming about 10 hours away, and I think that contributed a lot to that loss of follow-up. But he eventually did come back in July 2018 as well, still with discomfort. And as you can see here now, his vision's 2150, can hold 2100. And if you compare the photos from April 2018 to July 2018, you can clearly see progression towards the central visual axis of this area of ulceration. So he clearly has worsening disease. We actually initiated oral steroids immediately on high dose, especially given that his infectious workup was negative. And we referred him to rheumatology, who saw him within the week, and who recommended Rituximab given the severe nature and vision-threatening nature of his condition. Unfortunately, there were insurance delays in getting it Rituximab approved for this patient. And thus, a month passed, and then he came back in August for a routine exam. He complained of worsening vision for the past few days, and he had a flat anterior chamber at that moment. So clearly, he's perforated. This is not good. And in terms of where the area of perforation was, it appeared that actually in the inferior area of that christenic ulceration, there was a corneal flap already overlying an area that was probably previously side-L positive, although currently was side-L negative. So we elected out the point not to glue that area, given that it already self-sealed to avoid manipulation of the area. But we did recommend inpatient admission for a media IV salumetral, as well as inpatient initiation of Rituximab, given that it'd be easier to obtain as an inpatient. So what has happened to this patient afterwards? Well, I'm going to leave you guys in suspense. We'll go back to this patient at the end of the presentation. But first, I wanted to go over a few questions that appeared in my mind when this patient presented. The first is, in these cases of PUK, how often does perforation happen? And if medical management, such as gluing, or high-dose immunosuppression in inflammatory cases, doesn't work, what are the surgical outcomes if you need to do an emergent graft? And what are the surgical techniques utilized in these circumstances? So let's go over our first question, just how often does perforation happen in these cases? So this was a retrospective case series of patients who presented to a single center in Bristol to an ocular inflammation specialist of all cases of PUK over 2002 to 2012. The authors excluded infectious ideologies of perforation. These were only inflammatory cases of PUK. There were 85 eyes total, and 11, actually, upon perforation were already perforated. Five out of those 11 were initially attempted to glue, and the other six out of 11 went immediately to surgery, although all eventually required surgery. So even those five patients in which it was attempted to glue, the authors were not able to obtain anatomical success on that method. And my interpretation from this is that, actually, 11 out of 85 is higher than I would have expected, but granted, these are patients presenting to an ocular inflammation specialist, who probably actually are referred from other ophthalmologists. So this may not be the general PUK population, not at this tertiary center. And let's go to our second question, which is, if medical management doesn't work, what are the surgical outcomes? So this was an analysis of 32 eyes, also a retrospective case series, from 1980 to 1994 of all corneal perforations related to rheumatoid arthritis that presented to more fields. There were 32 eyes total, and in terms of the success, zero out of six patients who got glued had anatomic success, as in the globe, integrity was able to be preserved on that alone. Three out of four patients who had lamellar care to capacity had anatomic success, and 10 out of 22 patients who had PKPs had anatomic success. So my interpretation of this is that, gluing really doesn't seem to be too successful, at least in this case series, although graphs, at least in some cases, were able to reinstate globe integrity. Actually, the graph success was also lower than I would have anticipated, but that being said, these are patients who are actively inflamed, and furthermore, the period of time, 1980 to 1994, is before we had a lot of the newer immunosuppression that is available today, for example, where tuximab was not available then, so I think that this may not be applicable to today's breath of immunosuppression. Now, this was actually a retrospective study of all corneas needing care to plastic for tectonic indication, including infectious trauma, trauma inflammatory, among others, from 1991 to 2009 in the Singapore National Eye Center, and the authors analyzed tectonic failure, aka anatomical failure, loss of the globe integrity, and physiologic failure, aka loss of graft clarity. There were 362 eyes who presented who needed care to plastic for tectonic indications in this time period, which is almost 20 years. Now, when the authors performed a multivariate logistic regression, they found that factors that were associated with tectonic failure was actually lid disease, which was surprising to me, as well as receiving a lamellar graft or peripheral graft as compared to a central penetrating care to plastic. Now, with regards to the type of graft, the authors did note that patients with inflammatory conditions tended to get the ALKs and the peripheral grafts versus those with infectious conditions tended to get more of the central PKs. So I don't think that the populations are totally equal and I actually don't think that's really captured in this multivariate analysis. So it's hard to say what to make of the data regarding the type of graft, but I do think that the lid disease data is actually really interesting because that's not something that I would typically care about or think about if a patient presented with needing a tectonic graft, but perhaps it is something that we actually should think about. When the authors looked at risk factors for physiologic failure, they found that inflammation was definitely a risk factor for physiologic failure, which makes sense and is what we would expect. And they also found that greater graft size, greater than nine millimeters, was associated with decreased graft success. Now there's two ways, I think, to interpret this data. The first is that a larger graft is closer to the limbis and thus perhaps more risk of rejection, but that being said, I think perhaps those patients with more severe disease required the greater graft size. So I think that once again, it's hard to know what to make of this data in terms of the graft size. So let's say someone does need a surgical graft. What are the surgical techniques utilized? So for this patient, recall, he had a perforation that we think was inferior. You know, do we do a large diameter PKP? Do we do a small eccentric circular graft? Are there other shapes that we can do? Actually, when you look at the literature, there's really a wide array of techniques that have been utilized, very varied, for repairing these patients. So techniques described include large diameter grafts, sclerocharitoplasty, eccentric small grafts, biconvex, crescentic grafts, no star-shaped grafts, unfortunately. So this was actually a study that looked at large diameter grafts. So recall, we talked about large diameter grafts earlier. And this study was actually a retrospective case series that looked at 35 eyes with large diameter grafts at one institution. Large diameter, this study was defined as 8.75 millimeters or above, although I've also seen it defined as nine millimeters and higher. For reference in the OR, I've seen that we have tended to use about eight to 8.25 millimeter grafts for a normal patient. This study actually was a non-inflamed eye, so eyes with keratoconus and pollucid. And the authors argue that actually at follow-up, 33 out of 35 patients were without graft failure. And also that they had fairly good astigmatic outcomes. So what they wanted to show a point of in this article was that large endrographs are not so bad. I don't know if this really would apply to an actively inflamed patient, but once again, perhaps in a patient with active inflammation, maybe a large endrograph is really your only option. Now another technique described is scleral keratoplasty. So let's say you have a patient with a large central corneal ulcer that extends into the sclera, causing scleral necrosis. What do you do in that instance? So this was a study that described a technique whereby you actually get the entire globe from the eye bank, you fixate the globe, then you use a 14 millimeter trefine to make a mark onto the sclera. Then you do a partial lamellar sclera dissection that extends 0.5 millimeters onto the peripheral cornea, and then use a full thickness, 10 millimeter trefine to punch a full thickness corneal button. Now the recipient is prepared the same way using the 14 millimeter trefine and then the 10 millimeter trefine and then the two ends are sewn together. And it's thought that this method can preserve the angle and thus hopefully lead to less chance of glaucoma in the future. Now this study actually looked at eccentric round small diameter graphs, so graphs that are off center but round. And this was a retrospective case series that looked at seven patients with eccentric small graphs for various conditions, for example, inflammatory conditions, but also corneal wound burns, et cetera. The graphs were 3.0 to 5.5 millimeters in diameter. Follow-up mean was 21 months. And at follow-up, four out of seven patients had no significant irregular stigmatism. Although three out of the seven did have a regular stigmatism, all graphs had anatomic success. So the author's point that they were trying to make in this paper was that small eccentric graphs are able to succeed and may even not cause significant irregular stigmatism. However, what if you're worried that a small graph, even if you place in the periphery, the sutures are still gonna cross the visual axis? What are some other options? So other techniques described in the literature include chrysantic graphs, and as you can see here, the pupillary axis is spared, or biconvex graphs as seen here. And there are various techniques described in the literature for how to harvest these graphs accurately. So we went over a few questions, which is how often does perforation happen in these cases? If medical management doesn't work, what are the surgical outcomes? And what are some surgical techniques that haven't been described in the literature? So back to our patient. Recall that he had perforation and inpatient admission. He received IV cell imedrile that day and also started a cruximab two days later. And actually, his AC reformed, which was great as he did not require surgery and he was continued on an oral steroid taper. This is him actually November, so a few months later, and he looks actually really great. His vision's 2200, pinhole 2060, likely because of the irregular stigmatism and also central nature of the area of prior ulceration. And he's quiet. He has no scleritis, no active PUK, his AC's quiet. And I think an interesting question is in the future, when and if he may be a candidate for a PKP for visual indication, so not tectonic but visual indications. So there's actually not a lot of data regarding this. Literature does describe how some patients may get a tectonic graph because of active PUK that's perforated and then later on they get a visual rehabilitation graph, but there's no real data on a patient who's quiet just doing a graph for visual rehabilitation. So I think in the end it will be a judgment call as to when and if and how to immunosuppress this patient around the time of maybe him wanting or being a candidate for a visually restorative graft. Thank you so much, and that's the end of my presentation. I apologize, I didn't get a chance to introduce Katie. She kind of snuck up here, but I'll take a second just to introduce Brock, one of our glaucoma fellows. So Brock came to us from Oregon and we're really excited to have him here. He's been great oncologist speaking from a resident's perspective. We just love having both of them on Katie here, so I'll turn the time over to Brock. All right, so thank you for the introduction. So when I was deciding on what kind of topic to present, I kind of pulled the residents to see what they think would be the most interesting and beneficial to them. And I kept, the recurring theme kept being that there's so many migs, how do I make sense of them, and then how do I apply this to practice and what's the role of migs? So glaucoma is a leading cause of irreversible blindness in the world. The only modifiable risk factor for glaucoma is lowering IOP. Traditional treatment algorithms are typically start with medications, then we do laser, then we do surgery, typically trabeculectomy or glaucoma drainage devices. The problem is that the laser effect is only temporary, and we have high complication rates with our traditional glaucoma surgeries. Over 30% for traps and tubes with re-operation, over 20% in the trap versus tube study. So anybody that does glaucoma surgery is familiar with complications. So these are just a few of the complications that we see with trabeculectomy from the trap versus tube study. So I'm not gonna go down the entire list, but suffice it to say that the complications are very, very common. So even though migs have an increasing role in glaucoma management, none have matched trabeculectomy or tube shunts for lowering IOP. And so despite these complications, unfortunately, traps aren't going away anytime soon. So I think that it's important that we not lose sight of that and that the role that migs have. And the other thing is that migs kind of come and go, as we know with Cypass, but trabeculectomy has really kind of remained a big part of management since the 1960s. And then there are some people that argue whether or not migs stands for minimally invasive glaucoma surgery versus minimally effective glaucoma surgery. So, and then the other thing is this is not a comprehensive review. I'm kind of giving a general overview and just kind of some pearls of different migs and kind of how they are fitting into our treatment. Okay, so the cardinal features of migs, you know, there's an ab and terminal microincisional approach. The exceptions are in focus micro-shunt, which I'll talk about later, which is an ab external approach. And that there's minimal trauma and disruption to normal anatomy and physiology. They have demonstrable and reliable IOP lowering with an extremely high safety profile, rapid post-op recovery and minimal need for follow-up. So basically the polar opposite of trabeculectomy is what we're after here. So unfortunately, the reality is there's really no free lunch. Zen, which I'll talk about in a little bit, has needling rates as high as 47% in the literature. Hypotony is still problematic with some of the migs procedures, especially Cypass, which is no longer with us. And then also having the sudden unpredictable IOP spike with a cleft closure of Cypass, which you can see in the top right-hand photo here. That's just the cyclodialysis cleft. And then even these ice dens, which you think can be especially benign, you can cause an iatrogenic cyclodialysis cleft. So this is not something that is completely foolproof. Also, the hyphema rates can be over 30% with GAT. And I've seen some really impressive hyphemas here today. So these are not necessarily minimally invasive. So the migs roll. So basically it's reducing IOP as well as the medication burden. So these medications come with a lot of side effects. Getting the medications inside the eye is very challenging. If you've ever actually watched your patients instill a drop, you'll see, you'll learn a lot and you'll see that a lot of these patients just they can't tolerate the drops and they can't even get them in the eye. And then just a couple of side effects here on the left. We have the prostaglandin associated orbitopathy and then the familiar follicular reaction that we see with our alpha agnes. So generally they're less effective in lowering IOP than traditional tribes and tubes. But they do kind of fill the gap between patients needing lower IOP without warranting the high risk of these traditional trapezolectomies and tube shunts. And so these are generally used for mild and moderate glaucoma. So as you see in the middle, these are the patients that we're really targeting with our migs procedures. They're not for advanced patients and really not necessarily for ocular hypertensive patients. So there's really, there's so many options. So we have our trabecular outflow targets. We have our ice stent or trabecotone, Cahook dual blade, hydrous micro stent, adventurinal canaloplasty, Trab 360 trabeculotomy, our GAT, and then we have our supracoital, which are Cypass, which is no longer here. And then the ice stent supra, which is awaiting FDA approval. And then we have our ZEN, our infocus. The ZEN is here. The infocus is currently approved in Canada, but is currently awaiting approval here. And then we can target aqueous production with our ECP. So just even within the last five years, we've got a lot of new arrows in the quiver, but kind of where do they fit and how do we make use of all these devices? So just kind of starting into a general overview so that you kind of have a general sense of how these devices work. So the ice stent is one of the first that came out. So this is an AB internos insertion of these micro stents in the Schlens canal. So you can see that I've kind of tried to sort out just the average IOP reduction from all these devices. So it was 8.4 at two years with the original ice stent, which you see on the top right, and then 8.1 at one year with the new ice stent inject where you implant two of these ice stents in the trabecular mesh work. So these were actually randomized controlled trials and prospective randomized controlled trials. And then the medication reduction was about one drop at two years. Moving on, trabectum, I've never actually seen one of these, but this is an ab interno trabeculotomy using a combination of electrocotterate irrigation and aspiration. So same thing, ab interno kind of going over the top of the trabecular mesh work to create a trabeculotomy. So IOP reduction was 6.2 at two years when combined with cataract surgery. And this was just a meta analysis. There wasn't any, there haven't been any randomized controlled trials. And then medication reduction just under one drop at two years. Next kind of similar is the Cahook dual blade goniotomy. So it's an ab interno goniotomy unroofing Schlens canal. So we have an IOP reduction of about six at one year. And this is just a retrospective analysis. There haven't been any randomized controlled trials. Same thing about one drop at one year from retrospective review. Next we have the hydris, which we just started doing here within the past couple of weeks. So this is an ab interno insertion of this larger kind of micro stem that's placed in this Schlens canal. So here we're getting a higher IOP reduction 9.4 at two years when combined with cataract surgery. So you can see that's just have a, I'll just show you on the, sorry about that. So this is actually the inlet. So this is actually inserted into the canal, fluid drains from the anterior chamber into Schlens canal and eventually off the distal collector channels. Next we have ab interno canaloplasty. So this is an ab interno insertion of an illuminated micro catheter. So initially a cleft is created through the trabecular mesh work using an MBR blade. And then this micro catheter is actually inserted into that cleft and then is introduced 360 degrees around Schlens canal and then is slowly withdrawn at the same time, injecting viscoelastic to dilate the Schlens canal on the collector channels. So this can be done as a standalone surgery. So it doesn't require that the patient have a visually significant cataract. And the IOP reduction was about four and this is a case series review. Medication reduction was one at one year. And then similar, we have what we call a GAT or a Gonioscopic Assisted Transluminal Traveculotomy. Same thing where a cleft is initially made and then the micro catheter is passed through Schlens canal. And then instead of just withdrawing it directly through the other end, the other free end is actually grabbed as well. And then you're basically unroofing the entire trabecular mesh work 360 degrees creating a direct outflow from the anterior chamber and bypassing that trabecular mesh work. So this can also be done as a standalone surgery. IOP reduction on average was about 8.4 at one year. This is also a retrospective review. And then medication reduction was higher at about two at one year. These patients do have a higher rate of high FEMA. And like I said, it can be pretty impressive at times. Next, so kind of moving on past the trabecular mesh work now we're in the suprachoroidal space. So this is the side pass micro stem. So same thing inserted ab interno directly between the anterior chamber in the suprachoroidal space. So IOP reduction was about 7.4 when combined with cataract surgery at two years. And this was a randomized control trial. Unfortunately, or fortunately, depending on how you feel about it, this was withdrawn from the global market recently. After they reportedly showed that there was increased endothelial cell loss when compared to cataract surgery alone. You know, these have had other issues. It wasn't just that they only had endothelial cell loss. The clefts would close kind of unpredictably and you would get sudden IOP spikes where the patient's pressure would be eight and then all of a sudden it would be 50 the next time that you saw them. And so it was kind of without warning. So those were some of the other issues that you have with that. And then hypotomy was also an issue with this procedure. Giving a fluid tracking around the cyclonellysis cleft through the stem. So next is a similar, is Eistence supra. So this is kind of a competing device. So this is the same thing. It's kind of inserted abintero into the suprachoridil space. Has similar IOP reduction, 7.8 at two years. This is a prospective single arm clinical trial. It's approved in Europe. They're using it now. Currently waiting FDA approval here in the U.S. So next, kind of moving onto a subconjunctival approaches. So this is a zen gel stem. So same thing, abinterno insertion. It's kind of a flexible tube implant that allows fluid to drain from the anterior chamber into the subconjunctival space forming up the lab. So IOP reduction was nine at one year. Medication reduction was almost two at one year. This is a prospective single arm clinical trial. So this kind of outlines how the procedure is done. One of the biggest issues with these procedures that the needling rates are incredibly high, upwards of 50%, if you look at the studies. So these are, they do have their issues and they have all the issues that you see with blood formation as well. Although they tend to be a lot lower bloods. So next is the infocus microchunk. So this is a little bit different. It's an abexterno subconjunctival insertion. So you still have to do it pretty similar to what you'd do with the trabeculectomy. And then this tube shown is placed through the sclera into the anterior chamber. So the IOP reduction was 16.2 at three years when combined with cataract surgery. So there's a lot of optimism. This might kind of be, maybe not quite the holy grail of what we're looking at, but definitely better than a lot of the migs that we've used so far. So currently they're using this in Canada. ICOMN that is a big proponent of this surgery. That's what he's doing a lot of right now. And so I'm really excited and hopeful that this will get approval here in the US sooner than later. Next is our endocytophocicliculation, or ECP. So this is now targeting aqueous production. So this is an abinterno cycloadestruction procedure of the scillary body. So up to the right you can see, basically you're actually looking at a monitor while you're inside the patient's eye to be able to target. The scillary process almost looks like little teeth. And as you cauterize them, they kind of shrink up. So it's actually kind of satisfying procedure. You can see that you're actually having some impact. Unfortunately the medication, the IOP reduction is not great. It's about two, but in some of these patients that have end stage or that have glaucoma and you're really hesitant to do a standard diode procedure, I think this has a great role for these patients. And medication reduction was about one at one year. And this is a prospective case control study. So as far as patient selection, so I think we kind of need to take a mechanistic approach. So the first question you need to ask, does this patient have a cataract that will immediately disqualify some patients from some of the makes procedures that we just spoke of. So if they're only a candidate for standalone makes, that includes the Zen, the infocus, which we don't have here yet, have internal canaloplasty, GAT or ECP. So a lot of the angle surgeries that we just mentioned, they don't qualify unless they have a cataract to do surgery as well. So if they have a lot of conjunctival scarring from previous surgeries such as a scleral buckle, they're not gonna be a great candidate for a Zen or an infocus shunt. Maybe we need to consider targeting trabecular mesh work or UVO scleral pathways. Some people might argue that makes really has no role in a lot of these types of patients. So maybe just a standard tube shunt would be a better idea in some of these patients. And then is there inflammation present? So same thing, these patients are gonna do poorly with some conjunctival nigs if you're concerned about a lot of inflammation in them scarring down their blood. And then ECP, you're intentionally destroying that set of your processes. So probably not a great idea if they're already having a lot of inflammation. Is the angle scarred due to PAS? So a lot of times, sometimes you can get away with going to sneak your lysis if the PAS have been present within the past year. But MIGs really aren't approved for coposar glaucoma, but we've been using them here after following gonious sneak your lysis, you can actually get a good view of the angle. And then you can oftentimes still do some of these MIGs procedures to open things up after that's done. And then is there a chemical burn or OCP affecting the collector channels? So they're probably not gonna be a great candidate for trabecular outflow procedures. You could consider targeting the super facility space. Unfortunately, we don't really have any of those targets right now with PsiPAS being recalled. So again, these are some challenging patients to deal with. So kind of moving on to a case. So this was a 36-year-old monocular patient with juvenile open-angle glaucoma. He was enucleated. He had had multiple glaucoma surgeries and then had a ticicoli. So his right eye was enucleated and his left eye, his vision was 20-20. You can see his IOP was 26 on Latina Prosper monodine, COSOP, or PRESA, kind of on maximum medical therapy. And then he'd had a repeatable progression of the spurinazole step on hypervisual field testing. He's already had SLT. He's got a clear lens, open-angle. So kind of what would be the next step in management. You can see that he's got a spurinazole step. He's got a dischem on exam and then he's got inferior thinning on OCT. So are we gonna go with the traditional approach and do a trabeculectomy on this 36-year-old? Trabeculectomies, they do fail over time. And so you really wanna try to keep as many doors open as possible in a young patient. So first of all, he's only a candidate for standalone migs. He doesn't have a cataract. So the traditional pathway would be a trabeculectomy followed by a tube, then maybe a diode. So realistically, this patient's gonna live a lot longer than probably what those surgeries would get him time-wise. So like I said, you need to keep a lot of future surgical options open. So you could consider a standalone-angle surgeries. You could do canaloplasty or GAP. It would spare his conjunctiva for future surgeries. Or you could consider going to a sub-conjunctival surgery with the zen or the infocus. So for him, he ended up getting a GAP. You could also make the argument of trying canaloplasty. But if you remember, the IOP reduction was about four on average in patients from that study. So probably not likely to get him where he needs to be. So a GAP was chosen for this patient. And as you can see, he's done, initially he had a large hyphema, but then had done very well. Afterwards, IOP was 18 on just cosoptin-latanoprost. Vision was 20-20. And hopefully, ideally, this patient will will keep his vision for the remainder of his life depending on how long these work. Okay, and those are my references. And any questions that I can take? Yes? You mentioned several of these migs. Pressure drop about six to eight millimeters in volume of cataract surgery. Yeah. Not cataract surgery, just by itself. How much do you give for just taking the cataract down? Yeah, so if you look at a lot of studies, it's between on average about three and four points. So people that would argue that minimally effective glaucoma surgeries would point that out. But it's really not a huge pressure reduction that you're getting from a lot of these surgeries in there. They've also done cost analysis on a lot of these surgeries and the companies will tout that it is cost effective, but you do feel somewhat, I mean, when you see how much of these devices are costing patients, it's, and they're getting minimal benefit in a lot of these cases, it's hard to argue doing migs in certain patient populations. Yes? So when some of these devices get recalled, what happens? I mean, here you've got a device and somebody that's recalled or problem. I mean, what's the procedure? Yeah, so great question. So I can tell you there was, so I was on the AGS, American Glaucoma Society, was served the day that the side pass was recalled. And I mean, there were probably 50 emails from people, from different providers, asking what do we do? How do we approach the subject with the patients? So here what we've done at the Moran is that we made the decision to notify all the patients, track down all the patients that have had a side pass implanted. And then what we're doing, the companies make general recommendations for what to do. But basically what we're doing is we're bringing all of these patients back in, kind of explaining what this means. And then we're getting baseline gonioscopy to evaluate the placement of the side pass, see how close it is to the cornea, because presumably the closer it is to the cornea, the more anethyloial cell loss that you're gonna get. And so we're getting baseline specular microscopy counts, anethyloal counts, and then doing a baseline goniota to check the position of the side pass device. And the tricky thing is that a lot of these companies, they're saying that it's really easy to just go ahead and trim the side pass device. But I think that's been a lot more challenging when you actually talk to the people that have tried this. And so that's kind of been a source of frustration is that the companies want to say this is an easy fix, but in reality it's not. And they're kind of trying to save face with this device. So yes, patrols. So this is actually a perfect example of naive thinking on the part of these companies who produce in these things. It reminds me back in the days when enter chamber intraocular lenses had a whole proliferation of many, many different variations on designs of putting enter chamber lenses in. And I remember there was a forum, and I can still remember sitting there, and I'd say, but some of these, how are you gonna get that thing out? So we thought about that. And the response of our planners is that we're not gonna have to take it out. Well, it's totally naive. I mean, this kind of stuff happens so often, and I don't think anybody thought this through. I mean, this thing, the way it's set up, and I've talked to Norm's already mentioned, I mean, trying to get this thing out, all those little fenestrations of the rest, you get tissue in the, and I mean, you probably have to rip part of the coroid out, try to get it out. If indeed it's ultimately causing significant problems, either in this horrendously spiking, hard to control enterocular pressure, which would be a complete failure, right? We're doing this to control glaucoma. Well, the corny is failing. And then the ability to trim it, I mean, they've made it out of material that, I follow that very carefully. I don't think anybody's got a technique really to trim this thing. So we've put something in without understanding the full ramifications, without understanding that a hallmark of any biodevice is, there is a chance you're gonna have to get it out. And what's the one, the I-stand Supra? That's titanium. Yeah. What are you gonna do if that thing needs to be? And so, and I look at it and the rest, I said, well, there's probably a fair possibility. And you know, I don't know, but you look at it that this thing could, doesn't look like there's a strong area or it could be fixed, it could come out. Well, if titanium part this out, and there's a chance under with saccades or rubbing your eye that you're hitting the corny, corny is gonna fail. I don't know how you're gonna trim that. So I don't think, I think we continue repeating some of our same mistakes. And the one that always you have to ask yourself when you're talking about a biodevice is, in the chance this fails, which has been shown over and over again to be real, how are you gonna get it out? Or how are you gonna adjust it? And I think that's a big failure in regards to what people are doing in association with these areas. This is a hot area, I mean, it's a real, I mean, a lot of people are saying this is the whole new area of surgical glaucoma treatment. And you know, I think that it is exciting, but again, people have to consider those particular ramifications or just what it's gonna mean. Yeah. Where we are. I think the side passes is gonna be like, I hope it's not as bad as the Azar lens. The Azar lens, for those of you who don't remember, was a hot lens. This is back when people were doing entry capsule or cataract surgery. So they took the whole thing out, didn't have any place else, entered chamber lenses, and the hard lenses, which did fairly well support the test of time, but they hurt if you touched them because they were hard. And so this particular lens was just you just slap it in. It was a piece of cake. A lot of people weren't even using operating microscopes and that was as easy to stick in there. It was a disaster. It long term probably has 100% complication rate and getting that sucker out was just absolutely impossible and it would often rip the eye apart. And you know, and over time, I think side passes is gonna have an increasing issue problem. So I just, you know, warn those in the glaucoma side that a rule that you always need to consider and about advice is if you got to adjust it, how are you gonna do it? And if you got to get it out, how are you gonna get it out? And sadly, I see that being ignored. Yes. Always new things coming from a practical standpoint when someone's out of training, what's the process for glaucoma surgeons in the community learning to do these new procedures? Yeah, so, you know, from what I know from Roger Furlong, who I'm gonna be joining, he's in Missoula, Montana. And so trying to, he's far away from an academic center, trying to get kind of up to speed on these. I mean, you're kind of relying on the surgery reps to basically kind of coach you through doing these surgeries. So, you know, the typical scenario is that, you know, the rep comes up, they give a presentation, show some videos, take you to the wet lab, practice on some model eyes. And then the next day, you kind of, you try to stack up a number of these types of surgeries so that you get some reps in with them. You initially, you're followed for the, you know, the first, you know, however many number until you feel proficient with that type of surgery. But yeah, it's very, very different. So yeah, I think, I have the luxury of being in training right now with people that have done a lot of these and you know, they're just amazing surgeons. So that's, you know, I feel like that's gonna be really challenging once I'm out in practice and then just kind of, you know, these dealing with complications and then who to talk to when you're kind of in an isolated place like Montana. There's, you know, just a handful of glaucoma specialists in the whole state. And so I think, you know, keeping communication and with our teachers here is gonna be really, really, you know, important for me going forward for sure. Some of this looks very technically challenging too. I mean, some of the stuff you're proposing, like I said, and when things are particularly challenging, often I think that what is being done is not necessarily what had been proposed. That often results in complications. And again, the entry chamber lens, you know, a lot of people did just slap them in and they didn't go where they're supposed to. And so you had, you know, some of those haptics had the whole iris looped around the ciliary processes and you had this big keyhole pupil and obviously you're gonna get erosion and hyphaema and the rest. So that's the other thing that I look at that and I'm saying, I'll bet you there are a lot of people doing this and that's not where it's going. Yeah, yeah, I think there's definitely a misconception that NAICS are, you know, because it's minimally invasive that it's easy. And I can attest that I've been very humbled by learning a lot of these new surgeries. The side pass was probably the easiest out of all of them. Well, that's what made it popular. Exactly. So that's one of the biggest issues is because it was so easy, you know, we had a lot of, you know, a lot of people doing them. And, you know, I think that's one of the problems with that that we're gonna have to deal with that in fact a lot of coma specialists are gonna be the ones kind of dealing with all these issues down the line. So, yes, Dr. Mendelssohn. Well, we have to finish with a positive spin. So at least a couple positive things have come out of just the migs that they, and the surgeries that we're going to get out. First off, we're not very good gonioscopists, especially in surgery. And one of the things that's good about this is it's teaching us to do gonioscopy better, especially surgical gonioscopy. So for residents and for fellows in training, you get a better idea of the anatomy and what's going on. Second thing, though, is it's giving us a better understanding of Schlem's canal in the drainage of aqueous and what's going on. I mean, 20 years ago, Murray Johnstone in Seattle was looking at Schlem's canal and looking at trains. Nobody paid any attention to it, but at least now with these mixed devices, we're looking at how the aqueous drains. And as people are talking about, you want to try to put these in where you get maximum drainage and that there is definitely drainage zones that are coming out through Schlem's canal and that, again, when we're doing these procedures, this is going to give us a better understanding and maybe in the future we'll know exactly where you should put these in and where you get maximum drainage. And so, at least there's a couple of positives, maybe not so much for these devices, but for future devices that they could come out of this stack of what's going on. Right? Yes. So I think that's a great point. One thing that makes have really taught us a lot that's been incredibly valuable, as Nick was saying, about just the outflow system and how complicated it is. And that if you look at the Goldman equation, that episcleral venous pressure is just a tacked on value at the end of that equation that's just kind of always there. And, you know, we've discovered with the MIGs that there is absolutely kind of this floor of pressure lowering that regardless of the MIGs, if it's a conventional outflow type of device, you just can't get below that floor and in terms of pressure, you know. And so it's been fascinating to just watch that and kind of learn more about and try to understand that because it's definitely there. That was the main attraction, I think, of the side-pass shunt for us and why a number of, we have 110 of them here at the Moran that we're putting in. The attraction of it, it's easy putting it in, it was big. But the biggest thing is that it was a chance to bypass the conventional outflow system and maybe get away from that pressure floor that we keep hitting with all of the MIGs. And indeed, you do. I mean, the thing that is just so enticing about that side-pass is that early on, we have these really low pressures, which for so many of these patients, that's what we're aiming for. But then, unfortunately, they will, some of them blow up and now we've got the corny issue too, so we were really kind of suckered into that, unfortunately. But that was the attraction of it, is bypassing. And of course, that's what traditional traps and tubes do, is that they are a bypass. We almost call them bypass surgeries now because they bypass the conventional outflow system. Zen tries to do that, but Zen has a whole host of other problems. The end focus, as you mentioned, we're all just waiting for. And those that have access to it feel that it's just fantastic. You showed the number there, 16 millimeters on average lowering, and that's a whole different ball game compared to the other MIGs. One thing to think of about these MIGs, Dr. Harry was mentioning, most of those numbers that you showed, they're a very excellent presentation. Most of those numbers that you show are 6.2, say, millimeters pressure lowering below a non-medicated baseline. Most of these studies, they wash out all the medicines first. I wish MIGs were better at lowering pressure below the medicated baseline. If you look at the ice tent and the Pippinville Ice Tent Study, for example, it was about a 6.2 millimeter mercury lowering of pressure, but that was an unmedicated baseline. The amount of pressure lowering below the medicated baseline was maybe about one millimeter, almost just a little less than that. Just doesn't make it look as good when you're presenting that. MIGs have been fantastic in terms of, and we use them all and we like them all, and they've been great to teach us, and they're gonna continue to be part of it, but Dr. Ulster's point is so valid, though. I have tried to get a side pass out of an eye, a one that had actually extruded out, I'd probably from some eye rubbing or something like that, that had extruded out about week one or I think it was maybe day 10 or something like that. And so I went back in, I could not get that out, nor could I trim it with any scissor that was available to me. So that was, and is extraordinarily discouraging, just specifically about the side pass. So, you know, that's an unfortunate thing, and we do have to be absolutely right. You know, one thing about an omette valve or a bare valve valve, I can get those out. I can get those out. Any time it needs to come out, I can get it out. And I've had to remove some food. This side pass shot, it was no way. And I don't know, I've never tried to remove a Zen, but it's, again, it's gonna get tacked down, right at its point of entry through the square end. And in focus, I don't know, we'll see. I hope in focus it's as good as built, because we're all, I've taken a Zen out. It's, I mean, it was almost hard to find because it was so enveloped in tenons and it's such a tiny little stent. So, yeah, they just get completely encapsulated. And once you actually got it and grabbed it, were you able to... We were able, yeah, we were able to pull it out, yeah. Yeah, you could also trim it right up against the square end, I guess if you could. Yeah, that's nothing you can actually trim, but it does end, but, yeah. There's a risk, yeah. If we had to do an EK on these side pass patients, is there like a major issue with air going into that supercellular space? I don't know. I don't think so. Yeah, I don't think so. It's some mis-elastic in the side pass. Yeah, yeah, yeah. You know, I've actually gone in on one of the side pass shunts that I had that had this kind of catastrophic kind of pressure spike. I actually went in and injected viscoelastic into the shunt itself to just try to revitalize it. It seemed like it worked for a while. Not that much, but I really don't think that as an air exhaust, so to speak, that it'd be a problem for you. I don't think so. It's fascinating stuff. Thank you. Thank you.