Lecture: Point-2-Point with Dr. Malik Kahook: Managing Angle Closure Glaucoma: From Acute to Zipped

Point-2-Point with Dr. Malik Kahook is a new webinar series that will take place once per quarter. During these sessions, Dr. Kahook will invite two colleagues and lead a fast-paced panel discussion. The duration of these talks has been extended to 2 hours specifically to address as many audience questions as possible in response to feedback from past webinars. This session will cover angle closure glaucoma with a focus on short case vignettes and audience questions. Drs. Sarah Van Tassel and Syril Dorairaj will share their clinical knowledge and pearls for practice.

Dr. Malik Kahook, University of Colorado, USA
Dr. Syril Dorairaj, The Mayo Clinic, Jacksonville, Florida, USA
Dr. Sarah Van Tassel, Weill Cornell Medicine, New York, USA


DR KAHOOK: Good morning, everybody. This is Malik Kahook from the University of Colorado, and I’m really happy to be joining you today with some of the discussions we’ve been having over the months, continuing into a new program that we just started, called point-to-point, which I’ll describe here in a little bit. I do want to start off with a couple of slides here to do a proper introduction of the speakers, but before getting into that, I wanted to describe what point-to-point is. The last handful of calls that I’ve done through Cybersight, probably the last six or seven, oftentimes we run into the issue of running out of time. There are a lot of questions that come in, which is great. That’s exactly what we want. But an hour seems to be not enough to get to some of the questions, so we’re extending the period of questions for these Point-2-Point sessions, and we’re gonna bring in typically two discussants who can field some of the questions. I’ll be throwing out some of the questions and really going back and forth. We think of this as three friends sitting in a coffee shop, talking about exciting topics in glaucoma. I also think this is a chance to take a little bit of a break from everything that’s going on. The last time I was on was April. April 23rd, I believe, with Pradeep Ramulu. We were right in the thick of things in the US with COVID. Everybody was uncertain about what was going on. You can see the telling look on Sarah’s face. She was in New York and she was going through a lot during that time. And I was really hoping by now that we would be through this. But we’re starting to see numbers going up. Friends in India and Australia are going through big elevations right now, including us in the United States, in various states. So let’s take this time and talk about medicine, talk about glaucoma, try and put some of the worries to the side for a little bit, during these couple of hours, and I hope you can join us in doing that, and just learning, taking this time to learn. I do want to take a minute here and introduce, as I said, the panelists. The first is Sarah Van Tassel. She’s assistant professor of ophthalmology at Cornell. Director of the glaucoma service and the glaucoma fellowship, she has a great pedigree here, that way, way outpaces mine. She attended Cornell Medical College, she completed her residency at Cornell, and then Duke Fellowship, she was a Heed Fellow, and a member of the American academy of ophthalmology’s assessment committee. She’s a rising star. I used to hate it when people said that. Like come on, I’m a star already. But definitely someone who is a rising star, and I think you guys are all going to enjoy listening to what she has to say. As opposed to a rising star, a star who has been up there for a little while, Syril Dorairaj, from the Mayo Clinic. Syril has had a lot of great training, and I tried to condense it here with his permission. Residency at New York Eye and Ear, he did a lot of his training in New York, spent some time with Jeff Liebmann, Celso Tello, some of the greats in glaucoma, and went on to fellowship with Dr. Weirab. He’s one of the greats in imaging, and in my opinion, one of the people I go to for angle closure glaucoma. So most of the time is gonna be for question and answer, but I’m gonna be completely transparent with you. When it comes to angle closure glaucoma, it’s not unusual for me to grab a book and read about it, because definitions change, classifications change. I have a couple of things here on the slide just to get you thinking, and I’m gonna keep this slide up for a lot of the time. Primary angle closure suspect, iridotrabecular contact for greater than 180 degrees but no evidence of TM or ON damage, primary angle closure, iridotrabecular contact greater than 180 degrees with elevated IOP or PAS but no ON damage, and primary angle closure glaucoma, basically PAC with glaucomatous optic neuropathy. The way I think of it is the iris being pushed forward, pupillary block, malignant glaucoma, ciliary body swelling, or is the iris pulled forward, contracting membrane, something like ICE syndrome? That helps me understand what I need to do. Is an LPI gonna work or not work in this specific case? Do I need to do lens extraction? These are all things we’re gonna talk about. And you see some of the risk factors on the bottom left hand side that I think are common to a lot of publications, just going through a lot of the risk factors. What we’re gonna do is start off handing it to Syril Dorairaj, he’s gonna go through his slides to set the stage for the discussion, and after that, we’ll get to your questions. I’ll encourage you during his talk to start sending in questions. I have two computers, so I’ll be monitoring questions as they come in through, and Syril, as you take it away, we’ll get started with the question and answer. Thanks, Syril.

DR DORAIRAJ: Malik, I think I should take over the screen.

DR KAHOOK: You should have it right now. There you go. We see it.

DR DORAIRAJ: Thank you, Malik. It’s a pleasure. An honor to be sitting here with you and Sarah. To discuss something, very key points, about managing angle closure glaucoma from acute to zipped. Before we go into understanding the management part, it’s very important for us to understand that this glaucoma is not — though it’s angle closure, it’s not the same everywhere. In the world. Because — that’s where I’m going to start with. If you know, this is a preventable disease. Angle closure glaucoma is one of the leading causes of preventable disease. And sometimes, time is very essential. If you can’t detect it in time, there’s a progression of vision loss and glaucoma. If you can intervene and do something about this, you can actually prevent it from getting worse. But the most important point in actually the diagnosis — it’s the most important point. What we have to do is: The very key point that we have to do is to do a dynamic gonioscopy, understanding the angle closure. It’s very essential. When I was a resident or a medical student in 1992, I used to carry a book called Bailey and Loeb. People from India and Asia can actually know when you’re a surgical resident, you carry this Bailey and Love, and the first page in this Bailey and Love, it will say: If you don’t put your finger in it, you put your foot in it. What does it mean? When I was a medical student, if you are in the ER, if you have an acute abdomen patient, now we have CAT scan, we have all these things that we have to do. But there, during the emergency exam, it’s very essential you have to do a per rectal exam on all acute abdomen patients. Exactly the same way. If you want to diagnose angle closure glaucoma, and you’re going to go to the next steps, in the management, it’s very essential you have to do a gonioscopy. And it’s very important that you have to do a dynamic gonioscopy. That kind of changes the complete understanding. Because the dynamic gonioscopy actually gives us a clue about where exactly there is a blockade. And so then you can focus on relieving or taking care of that. So based on the gonioscopy, this is, as you said, I’ve been doing a lot of imaging, I did two fellowships in imaging, so my key point is: Whether it’s a posterior pushing mechanism or a pulling mechanism, broadly, you can classify three or four different types. Where exactly the blockade is. The pupillary block, also known as a relative pupillary block, happens in almost 70% of patients, where the iris is more sort of convex. You don’t have any mechanism, why this convex mechanism happens, and there is some sort of closure of trabecular meshwork. And then the next level of obstruction is actually from the ciliary body. Where there is a large ciliary body that is kind of pushing the peripheral iris, more anterior, and closing the angle. But Malik — people would use words like “rotation”. I would never use a word like rotation in these circumstances. It’s actually anteriorly placed. Rotation is where, as you said, in malignant glaucoma, the ciliary body is actually rotated. The next cause I would say is the lens-related cause. During my first residence in the 1990s, I would see a very hypermature, mature cataract, that can be causing this, but even now, if you can look at lens-related causes, especially in the United States, where I’m practicing, it’s becoming more common. So the key point, where we’re going towards a few points about how we are going to manage from acute to zipped, the key point is to actually understand where exactly the blockade is. So we have to do indentation gonioscopy. Otherwise, whatever the mechanism, whatever the classifications that you did, primary angle closure suspect, primary angle closure, or primary angle closure glaucoma, even though it’s broader, we don’t understand exactly where the blockade is happening, so we can focus on taking care of that. When you’re doing gonioscopy or imaging, there are a lot of things that interfere in the actual diagnosis. For example, if you’re going to do an understanding of where exactly the — how narrow the angles are, if you are saying 180-degree closure, based on primary angle closure suspect, if you’re going to see a temporal quadrant of 180, 90, it’s going to be open. You’re going to miss, because in the four quadrants, the superior angle is the narrowest of all, based on how broad the iris root is. Superior angle is the most narrow. And the next is lighting. If you’re going to do a test, especially a gonioscopy, in a very bright light, you’re going to miss it. It has to be done in total darkness. If you’re going to ask the patient to focus at a certain point, and the iris itself goes more convex — so the accommodation induced by looking at a certain point can cause more convex iris configuration that itself can give you an idea of: Oh, this is angle closure happening. And the mechanism of what exactly — what kind of lens you’re using, whether you’re going to use a Goldmann lens or a Zeiss lens, you can’t use a Goldmann lens, which is around 11 millimeters, to do an indentation gonioscopy, and to understand if the patient has plateau iris or lens-related — you need to have something very small which can indent the center of the cornea, so that you can actually see the mechanism. So if there is one point that if I have to tell about what’s happening, the one point is: Do your gonioscopy in total darkness. There’s almost 95% chances you will detect angle closure in this. And then the next point is the disparity. If you look at the paper that came in 2014, Tham’s paper, he said in Asians, it’s much more common than in Caucasians. The problem is, we’re missing it. We’re not actually doing gonioscopy. In India, when I was doing my first residency, all I had was a flashlight. I had to see whether this patient had narrow angles or not, until the patients come to the ER with an acute angle closure. So if you are diagnosing in the ZAP study or the other studies, coming with a lot of imaging and other things, the main point is we are missing it, because we don’t do gonioscopy. Even if you look at the Medicare data from the United States, not all physicians are doing it. So that’s the main thing. Even if you look at the paper that got published, there were 7 publications that did angle closure. And most of them are from Asia, and there’s no particular way by which the gonioscopy was done. And they were missing it. They’re basically missing it. So the data is actually not a true reflection of what’s happening in terms of angle closure. So the next thing is: My fellows, I do see fellows from Nigeria, and West Africa, you see towards the left side, that’s what she showed. You actually see: You have a slit lamp, but you don’t have a gonioscope. You don’t have power. You’re just using a flashlight to see and do a gonioscopy. So there’s a lot of discrepancy in how we diagnose angle closure. And that itself will kind of give us a clue about — what is the mechanism of angle closure so we can go to the next step. This is one of the studies where I looked into whether there is actually a difference from Caucasians to Chinese or from Asian eyes, why those people have more angle closure, compared to us. So this study was published in the British Journal of Ophthalmology in 2010. Yes, we are different, our eyes are different, people with Asian origin have far more risk of angle closure, because they have smaller anterior chamber depth and width. So we’re learning from a lot of publications prospective data coming from China and other places, it’s not a true reflective. We can’t take those points and say: This is exactly what we can actually do for our patients. If somebody is saying: Let’s do this, this is true, and we can do it in China or here — no, it’s not. So you need to be more focused towards your local population. So this is another study I did when I came to Mayo Clinic here, to see: Am I missing angle closure here in Caucasians? Yes, that’s a possibility. Because what’s happening is: When I did, because here at Mayo, in Florida, it’s predominantly a Caucasian population, and then we actually looked into the mechanism. Almost 70%, when compared to other Caucasian population studies, 70% are relative pupillary block mechanism. About 30% have non-relative pupillary block mechanism, plateau iris or other things. With the time, I’m just going to run. It’s very important that clinically significant angle closure is a neglected concept. It’s a neglected point. And it can be variable. It can be variable in the United States, it can be variable in China and Europe, in Africa. So it’s very important that we have to do a gonioscopy in the dark, to actually detect, and then if you can do a dynamic gonioscopy, to actually understand the mechanism, it’s very important to actually focus your next step in management. In the Caucasian population, what I have noticed is: People who are a little bit older, like 60, they have more lens-related angle closure. Younger patients have pupillary block angle closure. So if we do clear lens extraction or cataract extraction — it’s more focused towards your own population. That’s what I learned in this study, which just got published. So I’ll leave you with this slide, Malik. This is one of these slides that I actually made by my patient. From New York. I told her: I’m going to do a cataract extraction. She was 50. Her pressures were high. I did a PI. It didn’t work. She was on three medications. And I told her: This is not going to improve your vision. But I have to do a surgery to protect you from losing vision. She got — why are you doing this? She didn’t understand. But after the lens extraction, she was so happy. She’s not on any medication. It’s almost like a reversible disease. So the key point here is: It’s very important for us to understand the mechanism. What really is happening. And then focus towards the next point of: Management. Whether it can be acute angle closure or zipped.

DR KAHOOK: That’s great. Can you send me that cartoon? I’ll take over the screen here. I’ll reshare with that slide we were talking about. And some of the questions are already coming in. I think that talk highlighted a lot of the sort of bread and butter things we need to know about angle closure. In a way, it also shows the complexity of the disease, and trying to keep it straight. For trainees, for residents, fellows, in practice, including seasoned ophthalmologists, we have to have some ways to make it work for us. Not just in the patient population, but in our head. Do we intervene or not? Do we do PI or lens transaction? We’ll talk about all those things. One of the things is just diagnosing what you’re seeing. If you’re looking at the angle in your clinic, regular clinic, not talking about in academic research projects or anything like that, how do you document what you’re looking at with gonioscopy?

DR VAN TASSEL: That’s a great question and a tough one, because in part, you’re making notes to yourself so you can take good care of the patient, but in part, you’re making notes potentially for colleagues and for the future. So I just try to be as clear as possible. And I think for me, that means simply describing the structures and seeing rather than using some kind of complicated system. So my notes typically say things like ATM. 360. For anterior trabecular meshwork. Or PTM. And whichever quadrants I see posterior trabecular meshwork in, SS for scleral spur, or CBB for ciliary body band. I like to just describe what I see. And I think that question also asks about von Herick in reporting angles. I rely less on that, but I like to make a note to myself whether the anterior chamber is deep, moderate, or shallow. There’s some subjectivity to that, but you can use your own judgment to describe that.

DR KAHOOK: I know your background in doing a lot of UBM, but what do you do in clinic?

DR DORAIRAJ: Not really. Whether they’re open-angle or whatever it is, gonioscopy is one of the very essential steps in my practice. Every year, even if they’re open-angle, they have to undergo gonioscopy. As Sarah was saying, the key step is to understand the structures. Almost 50% of the time, if you look at the data, a comprehensive ophthalmologist is actually looking at something, but he doesn’t know what exactly it is. So if you are looking at an exfoliation and there is a pigment, we actually don’t know if it’s the pigmented trabecular meshwork or something else. So it’s very essential to actually document the structures that you are seeing. So though you have put something about primary angle closure suspect, primary angle closure, and primary angle closure glaucoma, there are three different things. If you see trabecular meshwork greater than 180 degrees, does it mean it’s primary angle closure suspect in a static gonioscopy? No, it’s very essential that you have to have a style of how you do a gonioscopy. For me, as I said, every structure that you see, whether it’s a trabecular meshwork, how well you see the root of the iris, how much pigmentation is there, color of the iris, and then every quadrant, and when you do, you make other things stable. Whenever you’re doing gonioscopy, it’s very essential that your lights, if you’re going to do it under darkroom conditions, it’s very essential that you have to document it, that you did the gonioscopy in dark. Otherwise, one of your colleagues will come and then he will do the same gonioscopy in full bright light, and you will see structures entirely different. So that is the problem with gonioscopy. It becomes more subjective. So I’m seeing something. My colleague is seeing something. He will diagnose — this patient doesn’t need a PI. So that is why it’s very essential. It’s not only just the structures that you see. The quadrants you see, it’s not only the lighting. And also the lens you use. If you’re using a Zeiss lens and doing indentation gonioscopy, you can actually see the plateau iris configuration. If you are using a lens which is like a Goldmann lens, and you’re trying to indent, you’re not kind of documenting the — it’s not a dynamic gonioscopy. So it’s the structure, the lighting, the quadrant, the lens that you are using. It’s an art. Unfortunately, as I said, it’s something we have to teach our residents, our fellows. Very key essential point in our understanding of glaucoma itself. Whether it’s open-angle, closed-angle, gonioscopy, though there are different grading systems, it’s important for us to actually teach our residents and keep showing them and also for them to have a particular style they will develop, so when they go back, they will repeat exactly the same steps. They turn off the light, use the lens like this, use not much of pressure, put your hand on the cheek, and then do the gonioscopy, and then see — do a dynamic gonioscopy, and then have some documentation. And you should also understand, Malik, what is it that you are trying to diagnose there? Are you trying to diagnose there is an appositional closure? Are you trying to diagnose there is a synechial closure? You want to do a PI or not? You want to take the patient for a lens extraction? So we thought an objective of what you’re going to accomplish — there’s no point doing any testing. So if you’re going to do gonioscopy, why am I doing gonioscopy? Am I trying to understand if the patient needs a PI? That’s very essential. We have to make our residents and fellows think like that. Why are you doing this test? Are you just doing it because you have to bill? Or what is it you are trying to understand? Because over time, even open-angle glaucoma — my colleagues from India, other places, can also know that open-angle can go into closed-angle. It can definitely happen.

DR KAHOOK: Since you started answering the question, about 100 more people signed on. So I need you to repeat everything you just said. No, I think here’s what my question is — and that could have been a book chapter, right? You were explaining exactly how you progressed through things, which is great. That’s the kind of stuff that at least I want to hear. But we had about 1500 people register for this. So you have people from various practices all over the world, who are listening to the answer, and I can tell you if I’m being honest with how I’m receiving the answer, if I’m in a busy practice, seeing 30 patients in a half day, and I’m thinking about doing all of these things, it’s not a surprise to me that a lot of physicians forget to do gonioscopy on specific patients. Because we’re overwhelmed in clinic. So Sarah, how do you do things in your clinic? And do you have any sort of tips or tricks for people, about incorporating gonioscopy into your practice, which is central, and as an aside, anybody who is listening in, if you go to the Cybersight library and look up some of the stuff by Lee Alward that’s in the library, I think that would be a great start for a lot of gonioscopy stuff, and his gonioscopy.org website is amazing for a lot of basic foundational skills. But how do you think of this, Sarah, in clinic? Do you do all of the things? Do you think through the whole process that Syril did, or are you on patient number 15 and he’s still doing gonioscopy on patient number one? How does that go?

DR VAN TASSEL: To echo what you said, I think gonioscopy.org resources are just outstanding. There’s a question in the queue about how you become an expert in gonioscopy. And I think the answer is you do it a lot, and you use excellent resources like gonioscopy.org. But I think in my clinic, I make it a point to gonio every single patient that I’ve never seen before. So every new patient to me, whether they’re new to my practice completely, or whether they’ve seen one of my colleagues but they’re seeing me for the first time, I gonio all those patients. And my technical staff knows that that’s my policy. So they’ll come knock on the door and interrupt me. Quick gonio, I’ll run out of the room, gonio that patient, and pop back in. The truth is, once you’ve become really skilled at gonioscopy, it’s not scary and it’s not quite the time sink that it is when you’re first learning. And then in terms of other patients, I try to do it yearly. I know there are patients who fall through the cracks, but I’ll make a note about when I want to gonio them next. And I gonio every patient that comes back with a pressure that’s higher than I expected, based on their last visit. So any inexplicable pressure elevation by someone — I gonio, essentially. Because you just have to make sure: Do they have new neovascularization of the angle? You can’t know that without gonio-ing. Are they newly occluded when they were open previously? Are there other clues about what might be going on? One of my mentors, Nate Radcliffe, says if the eye is numb, throw on a gonio lens. That’s a good policy also. A lot of patients will already be anesthetized when you’re seeing them, because they had Goldmann applanation tonometry, and it’s pretty quick to take a look. If they haven’t had it in the year prior, it’s reasonable to do it again.

DR KAHOOK: You just lost a lot of credibility by telling us who your mentor is. There’s no going back from that. You know, one of the things that can be a little bit embarrassing when you’re training residencies and fellows — our resident last year came to us from fellowship, she would go into a room, come out., and say it’s been two years since we did gonioscopy on this patient. It hasn’t been documented. I was like… That’s exactly what was intended in this situation, but it happened a few times in clinic. So even though I’ve focused on gonioscopy, no matter what, you’re going to miss some of the yearly visits where you’re trying to do gonioscopy, I would encourage everybody to do the best that you can. Hopefully you’re thinking about gonioscopy, you’re incorporating it, and it’s like we tell patients how to remember to use their drops. Just put it by your toothbrush and you’ll remember to do it, and they say I don’t brush my teeth every day. In our case, we have to put it with something we routinely put in clinic so we don’t forget. Here’s a question coming in from one of our friends in Puebla, Mexico. He says: Do you perform provocative tests on angle closure suspects? Do you do that, Syril? Provocative testing?

DR DORAIRAJ: If you are going to do UBM or anything, my way of actually documenting for angle closure, provocative testing, is doing a UBM in light and dark. So that’s kind of like a classic way that I learn. And then if I notice the same UBM, if you are going to do in each quadrant, superior, inferior, nasal, and temporal quadrant, when you shut down the light and do the testing again — like I said, I published on this topic — there’s 90% increase of detection of angle closure. So this is the provocative testing I typically do in my office even now. And I also use imaging to objectively quantify it. I’m doing the gonioscopy in dark, but when I’m actually doing a provocative testing, I want to actually show the patient the risk of having an angle closure. Or what is happening in the angles, whether it’s open or closed. It becomes much more easier for me to explain to them if I have a picture and doing a provocative testing, by doing the UBM in light and dark. And I also do the anterior segment OCT in light and dark, just to show them this is the provocative testing I very typically do. The other things, like prone position testing, or even doing darkroom test for almost 15 minutes, all those things are not kind of feasible in my office. At this time, I just do light and dark UBMs.

DR KAHOOK: Okay. Sarah, do you do anything specific that’s different than what Syril is saying? Or are you pretty much in line with what he’s saying?

DR VAN TASSEL: I don’t really do any provocative testing. I’m not confident that it’s been well justified in the literature. And honestly, I don’t have time for it in my clinic. So it has not been something that I have routinely done. I will say I do occasionally for various reasons dilate someone who has appositional contact of their angle, but does not have glaucoma, and for whatever reason, in the rare occasion that that happens, I do routinely check the IOP after dilation. So that is in essence a provocative test, but I’m typically not dilating them for the purpose of provocation. I’m dilating them for another reason.

DR KAHOOK: Can you tell me a little bit about indentation gonioscopy? So when you’re doing it in clinic, is there a particular lens that you use? There’s a question here about using a pediatric gonioscopy lens.

DR VAN TASSEL: I saw that question. I don’t even know about pediatric gonioscopy lenses. That’s something…

DR KAHOOK: That’s because Nate Radcliffe is your mentor!

DR VAN TASSEL: That’s right. I use a Volk four-mirror, and I do indent. I think the important thing about gonioscopy is making sure that you’ve taken your full look and that you’re happy with the gonioscopy you’ve performed before you indent, because you’re in essence ruining the virgin gonioscopy, once you start to push on the eye. You want to make sure that you’re almost — I tell the residents that you’re ice skating over the ocular surface. If you’re not occasionally seeing air in the interface between the gonio prism and the tear film, then you’re pushing too hard. It should really be very gentle contact, because you want to see what the angle looks like, with no pressure at all, and then once you see that, I think it’s reasonable to then apply pressure, because that can orient you more to the angle structure, and particularly in someone where you see a little bit of pigment, and you’re not sure: Is that a Sampaolesi’s line? In a person with an otherwise appositional angle? Or is that PTM? And you press on the eye. In many people, that will then open the angle structure such that you say: Ah, that’s scleral spur that I’m seeing now. And PTM that I’m seeing now, that I wasn’t seeing before. So in fact, this is an occludable angle, and what I had been seeing was some pigment on the termination of Descemet’s. So I do routinely perform indentation gonioscopy, but I think it’s critical that you do your gonioscopy before you indent.

DR KAHOOK: And Sarah, let me touch on a question for you that you brought up briefly. Maybe in a couple of minutes, just describe when do you use UBM, when do you use anterior segment OCT, what are the benefits and drawbacks of using one versus the other?

DR DORAIRAJ: Do you want me to talk about the indentation gonioscopy also?

DR KAHOOK: If you want to. But you get 30 seconds for that one.

DR DORAIRAJ: Okay. Let’s leave it there. The UBM and anterior segment OCT. Malik… As I was telling you, any test that I perform, I want to know: What is it that I’m getting out of it? So the difference between UBM and anterior segment OCT is anterior segment OCT is using light, the laser light, which can be stopped by the pigmented epithelium from the iris. So it’s not going beyond the iris. So anything which you are going to rule out, whether the angle itself — how open it is, what are the angle structures that you’re seeing, whether it’s an appositional closure, or even if you look at the configuration of the iris, if there’s synechial closure, then you can make a diagnosis based on the anterior segment OCT. But if you want to see the structures behind the iris, say ciliary body, if you’re having something like a posterior pushing mechanism, as you have put it there, anything that’s pushing it from the back, that’s kind of pushing the peripheral iris to close, then that’s where the UBM comes. When I used to do UBM in 2005, it’s much more cumbersome test. It’s as if you’re doing… All this is much more riskier. But the fourth generation UBM is far easier, almost like an anterior segment OCT, and you can get a lot more information, especially about the ciliary body or anything, especially where the posterior pushing mechanism is happening there. But when you look at the clarity of the structure, it’s almost like 1 micron. It’s almost like 1 micron. So you can actually make more diagnoses with UBM than with the anterior segment OCT. When you do a gonioscopy, anterior segment OCT is the same. Equivalent. But if I want to show to my patients what I am seeing with gonioscopy with anterior segment OCT, I take it and show it to them. It’s more objective testing, anterior segment OCT. It’s more done for patients, and then showing it to them, what’s really happening to quantify the angles. But if I want to actually understand the mechanism of angle closure, I do more UBM.

DR KAHOOK: I remember when I was in fellowship, the Visante OCT was in vogue then. We were doing a lot of anterior segment OCT with that device, and there was a lot of hope that it would replace gonioscopy or the variability in gonioscopy. And that didn’t really pan out. We have better devices that have more — that are better at imaging, I should say, from a size standpoint. We can get down to smaller features now, but it’s not routinely used in clinic.

DR DORAIRAJ: I agree, Malik. Visante went out of the market. It’s a 30 nanometer light, similar to what the higher resolution spectral domain OCTs are. But the problem is the warping of the image. If it’s go from the center, it’s straight. But if it’s at an angle, the periphery, the way it recreates the image, it can give a lot of false images. That’s where we had problems with the Visante. How the image is dewarped, what the image is, and what you are seeing, might be entirely different. The reflection of light is different. But the current generation is coming with spectral domain, where you can see the Schlemm’s canal in almost every patient, easily. You can actually see much more deeper structures also, much faster. Within 20 seconds, you can zoom 360 degrees, and it has artificial intelligence which pinpoints to the scleral spur. Which actually picks up the scleral spur and then shows whether there is an appositional closure, a synechial closure, which quadrant is closed, everything is fast, automated, objective, but unfortunately, not everywhere in the world people can afford this.

DR KAHOOK: That’s one of the problems. Just situational issues like that. There’s one thing I wanted to point out before I get to a question. Mina Pantcheva, my partner here at University of Colorado, says one can minimize the length of the split beam, not to shine in the eye and provoke miosis. It’s something that wasn’t mentioned out loud —

DR DORAIRAJ: Absolutely. I totally agree.

DR KAHOOK: There’s a question here that has to do with the introduction, where I was talking about COVID and how things have changed, and trying to forget about that. I guess I’m going against my own statement of trying to forget about things for a couple of hours. Because there is a question that I think is really good here. It says: In these challenging times of COVID, do you routinely perform gonioscopy? This question is good for you, Sarah. Since you’re in what was the epicenter, in New York. You saw a ton of patients. I know you and I have talked about some of the stuff that you guys went through. Do you change your practice — and maybe it’s not just gonioscopy. Maybe we can touch on visual field and OCT testing. What are you doing that’s different? And Syril, I’ll have a different question for you to follow.

DR VAN TASSEL: So when New York City was at the peak of the epidemic, sort of late March and early April, I was not seeing as many patients as usual. And I made a concerted effort to judiciously perform gonioscopy in patients in whom I thought it would make a difference in their clinical management. Incidentally, that was actually a high proportion of patients during COVID, because many of the people I was seeing were neovascular glaucoma, and acute IOP elevations, people whose eyes were pretty sick. Now that we in New York are doing pretty well, knock wood, I am back to routine gonioscopy. We do have the availability here of the disposable gonio prisms, and I think unfortunately it’s not a viable option for a sustainable protocol. Because the lenses aren’t cheap. They’re about $9 or $10 each. To throw that down the drain just doesn’t make sense long-term. But we have used those in certain instances. I’m cleaning my gonio lens with 70% isopropyl alcohol. And letting that dry. And I think that’s consistent with the best policies from the American Academy of Ophthalmology, and from the CDC, in terms of limiting disease transmission. But I think it’s hard to compromise on gonioscopy, because it is so, so critical, I think, for making the proper diagnosis for patients. And for taking good care of them. I think to echo what we were speaking about earlier, in terms of the dark room gonioscopy, that is actually what has become increasingly challenging in my practice, because we are now routinely leaving exam room doors open, to allow for optimal air ventilation in our practice. Which is a dramatic change from prior. But that means there’s sort of an extra step now associated with performing gonioscopy. Which is to say: I have to close the door in order to create complete darkness for a few moments.

DR KAHOOK: And Syril, maybe you can answer the visual field OCT question just briefly. What do you guys do differently between patients? Is there a cleaning protocol that you do? Or do you alternate devices? What do you do for other testing?

DR DORAIRAJ: It’s exactly the same situation here. But we are taking all the precautions here at Mayo. After every patient, every room is thoroughly cleaned, including the slit lamp. And currently I’m using the disposable gonioscopes. If it has to be reused, we use the isopropyl alcohol, clean it up, dry it, and we’re using it. For the visual fields, again, we have two rooms. And then we are kind of having the social distancing, and all those criteria, and then we’re also wiping the visual fields, and then making sure the patient wears the mask, and probably like you would have known, there are some guidelines about how to clean the visual fields, and there are lots of factors. When the patients wear the mask and do the visual fields, there is some risk that they might have some new visual field defects. We’ve told the technicians what to expect. These are all new things. We define something unusual, if the patients are taking a little bit longer, the test is a little off, we are kind of going very slowly, not only just cleaning the visual fields, but also making sure it’s repeatable.

DR KAHOOK: Okay. We’re all going through this and learning together. Right? We’ve got great recommendations from Academy, from AGS, from different groups around the world, who are talking about their experiences. That’s how we found out about some of the visual field defects that are mask-related, when people are wearing those. Certainly we’re seeing those, fogging up of the lens and issues like that. One thing I wanted to touch on here, before moving to some of the other questions, and I’ll reiterate to everyone: We’re getting a ton of questions, and I’ll try to get through as many as possible, including those submitted before the session. You see this in front of you. This is a patient who is post-LPI. Sarah, what did I do wrong here?

DR VAN TASSEL: This LPI is right at the lid margin. You’re highlighting it with your arrow. So this means that unfortunately each time this patient blinks, because of the prismatic effect of the tear film, potentially they are getting a little beam of light stimulating their retina, and there are few things more annoying to patients, and probably nothing more annoying to doctors than that beam of light.

DR KAHOOK: Yeah, I wanted to touch on this. I’m gonna show a couple of slides here and I’m gonna talk to both of you about some of the issues, before we move on to a slightly different topic. I showed you guys this slide before. We hopped on the Zoom meetings here. There was a lot of debate, a few years ago, about whether we should go superiorly or temporally with our LPI. Initially I was doing everything superiorly, at 11:00 or 1:00. And I was doing that because that was the way that I was trained. I avoided 12:00 because bubbles can actually hinder your view after you do a few shots. When I started going to temporal, there was a lot of benefit. We’re away from the eyelid. The other benefit is that the ciliary processes are closer and infringe on the eyelid, and certainly my experience with the temporal LPI, we’ve seen less of an issue when it comes to patients complaining. There have been some studies looking at this. Like everything in glaucoma, the studies kind of disagree with each other, as to how to do it. This is from Spaeth and colleagues, where they found 80% of LPI patients had no issues, 9% of eyes with completely covered LPIs had an issue, as opposed to 20% with partially covered LPIs, and 26% with partially exposed. This was not prospective. The questionnaires were prospective, but it’s a slightly different design. Basically they’re saying visual symptoms following LPI are more likely to occur when you have a partially or fully exposed laser iridotomy as opposed to something that is fully covered. This came out from Pradeep Ramulu and a few others, as you can see listed here. This was a prospective study, randomized, but the randomization was by patient, not by eye. There was no right/left eye comparison of temporal versus superior, and they got a questionnaire two weeks after the LPI. So there’s a question here of whether that was enough time to show some of these issues that can arise, or does that change after two more weeks or a month. Some other studies looked at a month timeline instead of two weeks. And they recommended that the LPI should go where it was easiest to access. There wasn’t much of a difference with visual disturbances, superior versus inferior. I emailed Pradeep to get his thoughts on how to do things differently, and he said the study was perfect. I wouldn’t change anything. No, he didn’t say that. He said what he would do is he would take pictures of all the peripheral iridotomies, so there would be not just the physician saying I did it here, but actual documentation of it, and also a pain scale. Was there difference in discomfort, temporal versus superior. This is by varying colleagues, Ike Ahmed and friends, prospectively, but in this case, they randomized within the patient. Each eye got a different type, temporal or superior, and the patient didn’t know which one was which. They came up with slightly different conclusions, also looked at pain, and concluded that temporal placement of LPI is safe and less likely to result in linear dysphotopsias, but there was more pain with the temporal. That’s an important point. It isn’t as easy as saying I’m always gonna go temporal. Some cases you’re gonna go superior, especially if you can get it completely under the lid. Because we don’t have a ton of time to go through all of this stuff, I just want to see if you guys can agree that from a settings standpoint, this is what you guys do. From an argon laser kind of outdated term — argon, right? Diode laser, with lighter irides, we use a longer pulse. With brown irides, we usually use more spots. 25 to 100. And I’m showing these here, so during the recording, people can go back and look at the numbers. They don’t necessarily have to write down all of the numbers at this point. And then of course we have two different methods. We can go with the thermal type approach or we can go with the photodisruptive type approach, like ND YAG laser. In this case, one or two pulses usually can get you through. And you don’t have to really — you can pretty much do any type of iris. The very thick iris or the very thin iris, when it comes to ND YAG. And usually if we’re using pilocarpine, we can get through one or two spots. Hopefully you can see this link. My screen is full of different boxes. I don’t think that’s your view. I think you can see the entire slide here. I hope, at least. I recorded a small talk on LPI. Settings, side effects, you know, adverse events. Why we use a lens, different lenses. So you guys — whoever is interested can go to this YouTube link, and watch the whole video. It’s about 10 minutes long or so. When it comes to temporal or superior placement, Sarah, what do you do and why do you do it one way or another?

DR VAN TASSEL: You know, I’m junior enough in my training that Ike’s paper had already made a splash in 2014 before I was really doing many LPIs. So I think the trends kind of shifted toward doing them at 3:00 and 9:00 at that point. So I have pretty much done them mostly at 3:00 and 9:00. And honestly, I think it’s a little technically easier also. They’re easy to transilluminate in the office. You don’t have to yank on the lid and ask people to look in all kinds of different directions. I would say I’m not overwhelmingly convinced that the dysphotopsias probably differ all that much. But I’m happy to do them at 3:00 and 9:00.

DR KAHOOK: Syril, what do you do?

DR DORAIRAJ: It’s almost the same, Malik. In terms of Pradeep’s paper, what was actually said is true. The dysphotopsia, whether you do it in superior or temporal quadrant, it’s almost the same. But in terms of the pain, I do both. I’ve done both. I do surgical iridectomy, and I’ve seen sometimes dysphotopsia depends on a number of things. It’s the size of the openings you create, if it’s too big or has kind of hazy with a lot of fibers around, that kind of distorts the image. Or if it’s exactly in the lid margin, that’s also a problem. And if you are doing it with a really thick brown iris, and trying to get into the superior quadrant, where the iris is far thicker, it can be much more of a problem, and then the inflammation is far higher in them. And when you compare with the temporal quadrant, which is much easier, in the lighter iris, blue or gray iris, it’s far easier, and you can transilluminate and find out whether it’s open or not. But there are no actual studies which prove which is beneficial, in terms of progression, because you know whether it’s a superior quadrant, inferior, or nasal or temporal. Superior quadrant is the most narrow of all. And if you see if there’s more apposition there, you’re trying to open there. Would it be beneficial to do that? Are you just placing a temporal quadrant that will completely arrest the progression? I have no idea, but there’s no prospective study looking into it. But in terms of comparing the outcomes, especially the pain and the other things, it’s almost the same. Right now, I don’t have any kind of inclination towards one or the other.

DR KAHOOK: Are there any cases where you do an LPI without a lens? Without using an LPI lens?

DR VAN TASSEL: I can’t think that that’s happened to me recently. I’ll do YAG capsulotomies without a lens now and again. But I typically use a lens if I can. I like the stability of the eye to control.

DR KAHOOK: I think that’s one of the major things. You have stability to keep the eyelids out of the way. It’s safer. It’s a little bit of a heat sink with the lens. If you do have a little bit of an ooze or bleed, it’s easier to tamponade that by pushing on the lens, to control the pressure. Let’s switch gears here and start talking about lens extraction, or the EAGLE trial, stuff that’s out there. Sarah, maybe without putting you on the spot too much, tell me what your impressions of what the EAGLE trial says, and how you use that in practice, and Syril and I can tell you why you’re wrong after that.

DR DORAIRAJ: You’re getting me in trouble!

DR VAN TASSEL: This has been an exciting decade for laser trials. We have — although laser techniques themselves haven’t changed, we have a growing volume of prospective studies looking at things we maybe want to know about lasers. The EAGLE study was a multicenter prospective randomized clinical trial that looked at clear lens extraction versus LPI in patients who either had primary angle closure and elevated IOP, or patients with primary angle closure glaucoma. And there was more primary angle closure glaucoma in their group than primary angle closure. And essentially what they found is that at three years, on average, the eye pressure was about a millimeter lower in the clear lens extraction group than in the LPI group. That number, 1 millimeter of mercury, probably isn’t clinically significant, and it’s also not surprising, because the practitioners in the study were allowed to treat to a target IOP. So not surprising that the groups would have similar pressures. But I think the biggest findings were that only about 20% of patients in the clear lens extraction group needed additional eye drops to meet their target pressure, whereas nearly 70% of patients in the LPI group needed additional therapy. And furthermore, with respect to moving on to glaucoma surgery, only one person in the clear lens extraction group needed incisional glaucoma surgery. So they were interested in looking at safety, efficacy, cost, quality of life. They looked at a number of metrics. I think in terms of quality of life, it’s not surprising that they found the clear lens extraction group did a little bit better. But I think you have to take that with a grain of salt, because clear lens extraction in a hyperopic patient is essentially refractive surgery. You’re taking someone who — in this study, their range of refractions was between plano and +3. You’re taking that person and essentially making them an emmetrope. People like improved vision. I think the cost data showed there were more up front costs with clear lens extraction, than with LPI, but if you take into effect the quality of life, that starts to look acceptable over a longer horizon. But I think the most important finding is the clinical findings, the data that the patients tended to do better in the clear lens extraction group. I think that the challenge here is thinking about the external validity of these findings. Typically, when I think about external validity, I’m thinking about whether or not the patient group matches my own practice. I think in this particular study, we also have to ask: Does the doctor group match our skill set? I think when you’re talking about clear lens extraction, in a short eye, you’re taking on some risk. A clear lens means that person was seeing okay before you touched them. So you want to make sure, very certain, that they’re gonna see equally well, if not better, once you’re done. And I think the other thing to keep in mind is that cataract surgery, clear lens extraction, in short eyes is not always technically easy. I think that the cataract surgeries that I do in short eyes and angle closure eyes are some of the toughest eyes that I do. So I think that these findings are only applicable to someone’s practice if they are a skilled phaco surgeon. And the group of doctors in this study were very skilled phaco surgeons. All well trained both in comprehensive ophthalmology and in glaucoma. So I think that if you are in fact a skilled phaco surgeon, you can consider applying these findings to your practice. In my practice, I tend not to remove truly clear lenses. But I think that these findings motivate me to think about early cataract surgery in patients with similar findings, elevated IOP, and angle closure or angle closure glaucoma. If you might have been on the fence between an early phaco, versus LPI.

DR KAHOOK: And Syril, has the EAGLE data that came out — has that changed your practice in any way? Are you more likely to do something, after going through, reading that study?

DR DORAIRAJ: I agree, Malik. If you see, my ending slide was something very related to what the EAGLE study was. The patient was in their 50s, a female, with pressures more than 30, with synechiae, but one thing — if you look at the data much more closely in the EAGLE study, what you have to see is: Who are the patients who underwent — you call it “clear lens extraction”. If you see the age, the age of those patients are around — in the mid-60s to around 65, 67. So I did maybe 18 to 20 cataract surgeries this week. In the United States, let’s not take my practice — if you look at the United States, average age of patients who are undergoing cataract surgery, according to the medical data, is 65. 65. Okay? So the data here, the EAGLE study data, the patients are women. Okay? Predominantly. 60% of them are women. And also age is around 67. And the next point is almost 60% of them had primary angle closure glaucoma, PACG patients. So you have to look at the data. You’re not going to — though they enroll patients 50 and over, you’re not going to extrapolate it and then say: I’m going to do clear lens extraction on a 50-year-old. No, not really. Okay? So you have to — as Sarah was saying, doing cataract surgery in a hypermetrope or a smaller eye, there’s more risk. It takes more time. You will end up with more complications. So you have to look at the patient data and then extrapolate it to your patient population, and then see whether this is what they’re trying to tell you. But it’s an option. In my practice, it’s an option. If a younger patient, primary angle closure glaucoma, pressures of more than 30, having synechiae, these are the patients. But if you look at the clear lens extraction, who had benefit, almost 9% or 10% of them also had goniosynechialysis. It’s not just the clear lens extraction they underwent. They underwent something else beyond that. So these patients had something beyond just the cataract, and they had some benefit out of it. If you want to ask me whether I’m going to do the same thing, it’s already the same thing that I’m doing. If you look at the data, patients are in their 60s, having some sort of cataract, if they have angle closure, if they have synechiae, and if there are more than 30, it’s given. But this is a much more valid way to show it. And you should give it — but the point is we should not take it to a 50-year-old.

DR KAHOOK: One point I want to make here, for the Point-2-Point format, we’re an hour in. This is when most sessions would end, but we have another hour to do questions. We’re gonna go for another half hour to an hour, as much as we need to get through, a ton of these questions that are coming through. So Syril, let’s just pivot a little bit to the ZAP study, the ZAP trial, from David Friedman and colleagues. Can you just give a one-minute blurb on what the ZAP looked at? And sort of what the conclusion was?

DR DORAIRAJ: They reflected a particular group of populations. ZAP study, also known as the angle closure prevention study, the basic idea — the concept was to see whether doing LPI in a patient who was diagnosed with primary angle closure suspect, with a static gonioscopy, if you don’t see more than 180 degrees of trabecular meshwork, would doing a PI in them be of benefit or not? It’s one of the largest groups of patients that were prospectively enrolled. In Guangzhou Province. They did a lot of testing and underwent PI in one eye and prospectively looked into whether the other eye was going to develop angle closure, or if they’re going to the next stage of glaucoma, PACG, will they develop anything like that. So we might argue about number of things that — whether proposing cataract surgery for someone, or doing a PI, iridoplasty in someone, but this gave an idea, saying: In one of the most riskiest populations, we always think: Asians have a much higher risk of angle closure. They kind of gave an idea — it’s not really necessary. Because these patients don’t really progress to develop an angle closure. And it was not of any benefit. This was an eye-opener.

DR VAN TASSEL: I differ with the assertion that it didn’t show a benefit, though. I would argue — I mean, their primary endpoints —

DR KAHOOK: It took an hour for the two of you to get in a fight. This is good. Go at him, Sarah!

DR VAN TASSEL: Backing up, so the listeners are with us, the EAGLE study is a different population. The EAGLE study is people with — their angle is closed or partially closed, and either have elevated IOP or glaucoma. Now we’re pivoting to ZAP. These are just people who are seen in the community and screened for an occludable angle. So this is very similar in my practice to people who saw an optometrist in the community, for example, and were told incidentally that they have the finding that their angle is not open. And their primary endpoints were three things: Elevated IOP greater than 24 at two visits, development of peripheral anterior synechiae, because none of the people had it at the screened visit, or an attack of angle closure glaucoma. And if you look at all three of those primary endpoints, almost twice as many people in the control group met that endpoint, compared with people in the LPI group, and patients served as their own control, because they had an LPI in one eye, and no LPI in the other eye. So if we’re looking at their primary outcomes, 19 treated eyes and 36 non-treated eyes, and that’s their primary endpoint, I think the more exciting finding is the question about acute angle closure glaucoma. Because that’s what these patients fear. They’ve been told when they’re outside a general or an optometrist’s office, they need to present for LPI within the next 24 hours, because they’re gonna go blind if they don’t have an LPI. What this trial showed us is that the vast majority of patients don’t go into acute angle closure. Three control eyes and one LPI eye went into angle closure, with provocation, with dilation, and two additional control eyes, for a total of five, had angle closure without — an attack of angle closure without provocation. So there is a benefit to LPI. It’s just a far lesser benefit, perhaps, than we thought previously. The number needed to treat is very, very high. So I don’t think we can say LPI has no benefit. But I think we can counsel our patients that one reasonable option in a certain context is perhaps observation.

DR KAHOOK: Let me ask you both… Kind of a yes or no answer. For Syril, if you were in this category, of narrow angles, let’s say they’re occludable, kind of mimicking who got enrolled into ZAP with all the criteria that Sarah just went over and that you went over, would you get an LPI?

DR DORAIRAJ: So the argument is whether… I never said I wouldn’t do it.

DR KAHOOK: Would you do it on yourself, though? Would you have somebody — would you have me do your LPI? I just confounded the answer.

DR DORAIRAJ: Ha-ha-ha! I would definitely do it. The problem is, if you look at the data, they kind of took away — as Sarah was saying, whether I would do it, it’s just their findings. It’s interesting to see the most riskiest population who have almost 30 million people with primary angle closure suspects, having to say — this is an easy step. I’m not going to argue with that. That’s their finding. But who are the patients they excluded? They excluded patients, under whatever prone provocative or darkroom testing, if they noticed an IOP spike, they excluded that. So it’s kind of giving it to you. You’re not taking patients — the risk of acute angle closure. But if you look at other groups of patients who had probably — you remember Wilensky’s study that came from Europe. 6% of his study population had an acute angle closure glaucoma. An attack, actually. And then when I was a resident, probably you know Vitamas — he published a paper looking at patients who were primary angle closure suspects, and almost 22%, 25% of the patient population within three years developed synechiae, glaucoma, so it’s a significant number in my patient population. So I wouldn’t take it. I wouldn’t take it. But you have to look at the risk factors. Risk factors, whether they’re a hypermetrope, how thick the iris is, how convex the iris is, what is the IOP, family history, everything. I won’t rush into it. That is something I have learned. Though there is some sort of appositional closure, but if there is a synechial closure that’s developing, I would definitely offer it to them, whether it’s 5 degrees, 10 degrees, or anything like that.

DR KAHOOK: I think what we’re noticing in all of these studies, not just the LPI, symptomatic, visual disturbances, ZAP, EAGLE, a lot of times what gets the air play is the conclusion, and we talk to our residents and fellows about the conclusion. Early in my career and the resident would ask the question, I would say: Here’s the conclusion. And now when I get asked the question, it’s like… Well, it really depends. In the past 15 years of practice, it’s taught me that you have to do X, Y, and Z, and pick this patient versus that patient. Maybe I don’t pull the trigger to do a trab as fast on this group of patients versus that, because my experience has shown that they’re stable for years after a progression episode. That’s one of the take-home messages. In a format like this, when we’re doing the webinar, we can hit the highlights. I think we did that for EAGLE and ZAP, but the encouragement would be to go and dig in and see how it applies to your patient population. When the authors of ZAP were asked at a conference — I saw this on the internet recently — if they would get the LPI, they’re like yeah, I would get the LPI. I think really we have to look at those certain things. Do either of you do water provocative testing?


DR KAHOOK: Syril, do you do it?

DR DORAIRAJ: You’re getting into a point here. I have fellows and I have collaborators from Brazil, Remo is a big proponent of water drinking.

DR KAHOOK: He’s the one who taught me about water drinking. What do you do?

DR DORAIRAJ: Have you done the water drinking test yourself?

DR KAHOOK: I have not.

DR DORAIRAJ: Kaveh made me do it.

DR KAHOOK: Then I’ll have to do it. That’s what we’re doing.

DR DORAIRAJ: Whatever the concept is, the concept of coming into a picture where there’s a lot of extra fluid coming into the choroid, and that increases the chance of precipitating the acute angle closure — or detecting — I don’t buy it. I actually published two, three papers on the validity, looking into some collaborators from Brazil. No. It doesn’t have a place in my practice.


DR DORAIRAJ: I would say that.

DR KAHOOK: I’m gonna go through a few questions.

DR DORAIRAJ: Do you do it?

DR KAHOOK: I don’t do it in clinic. I haven’t done it myself. And maybe I should. Maybe I’ll call you tonight after I’ve done it. I’ll have my wife call you and she’ll let you know how it went. Let me ask some rapid questions here. Again, we have a bunch of questions that we’ll try and get through. I’m gonna go to random questions that are not necessarily gonna tie into each other, but let’s just try to get it through as many of these as we can. Some of these I’m reading for the first time here. The first question — this is for you, Sarah — if the elevated IOP and angle closure is caused by weak zonules in a short axial length patient, LPI has been done in the past, is this angle closure primary or secondary? I guess that’s more of a definitional thing. Right?

DR VAN TASSEL: Yeah, that’s philosophical or teleological. I think probably secondary. In terms of how I would code it. But in the States, coding is more of a billing matter than a true diagnostic matter.

DR KAHOOK: That gets back to my initial slide that I had on for a little bit. The mechanism is really what I look at. In that case, I’m thinking: How do I reverse this? This lens has zonulopathy. What am I gonna do to overcome that? It’s really about the intervention rather than the classification.

DR DORAIRAJ: I agree, Malik. These are typical patients with pseudoexfoliation, where there is weak zonules, lens-related causes of angle closure, rather than the convex iris configuration. So zonular involvement, I would rather focus on — the outcome is the lens moving forward.

DR VAN TASSEL: And you also have to be careful. Marfanoid eyes can do that, microspherophakia. In most of those eyes the lens has to go, but proceed with extraordinary caution.

DR KAHOOK: Lens has to go is the answer for most things in my clinic. So here’s a question. Let’s go with Syril first. How do you reduce the risk of post-ND YAG or just general LPI complications, like floaters? Is there anything that you can do, or they touch on in the same question on shadows, webs, crescents, we talked about the positioning, but do you have a lot of patients who experience floaters, post-LPI?

DR DORAIRAJ: Fortunately no. Fortunately for me, no. So I typically used to do 300 to 400 of these a year before. Because I was doing a prospective study, comparing, enrolling the Caucasian population here at Mayo. Most of them, if they decided to undergo PI, this population is entirely different. But even though it’s uneventful, there’s no bleeding, I still put them on prednisolone, Pred Forte, four times a day for 7 days and then stop it. In terms of floaters, I’ve not noticed it. Though there’s some data. My typical approach is to continue the steroids for one week and then stop it.

DR KAHOOK: Sarah, do you use thermal versus photodisruptive for LPI? Do you always use YAG? Where are the circumstances where you might use one over the other?

DR VAN TASSEL: I almost always pretreat. Even in light irides, I find that you can sometimes find a slightly more pigmented area that perhaps you get slightly less bleeding, and things are a little thinner, and I would say as a secondary benefit, I like to mark the spot for my trainees, because I often do — especially with junior residents, I’ll do the pretreatment myself. And then they’ll pop through with the YAG, and I think it’s nice to show them the spot.

DR KAHOOK: That’s great. I don’t do that. So that’s a really good point. And maybe we should be doing more of that. Syril, do you use either/or, or how do you proceed?

DR DORAIRAJ: I used to do argons exactly the way Sarah was saying, especially when I was in New York. I still pretreat with the argon, and then go with the YAG, but after I came here, my patients here are lighter iris, blue, gray — it’s easier for me to finish it within two or three spots with YAG. And then I just find a spot where I feel like it’s easier to get through, and I’ve stopped using it since the last 8, 9 years. I just go with the YAG.

DR KAHOOK: What’s your go-to lens, Syril?

DR DORAIRAJ: Abraham lens. That’s what I’ve been using. Not changed anything.

DR KAHOOK: Okay. Let’s see the next question here. Does adding — so argon LPI to just standard LPI lead to wider angle, and more persistent opening? I think they’re referring maybe to iridoplasty in this case, which we can get into in a little bit. We’ll get into that topic towards the end. I sense that’s another fight between the two of you, and I want to save that for the end. A question about posting reading info on principles of gonioscopy. Again, I think you heard from all three of us that gonioscopy.org from Lee Alward is the place to go. Again, gonioscopy.org. And he walks through everything. It’s amazing. And he also has further content on Cybersight. So please visit the library on Cybersight as well. Hopefully that’s helpful to you. If you decide clear lens extraction, is there an age range, Sarah? I know you touched on this a little bit, but how do you factor that in? If somebody is going to be left without the ability to accommodate at a specific age? Is there sort of an artificial cutoff in your head?

DR VAN TASSEL: I would say again, I don’t ever really do true clear lens extraction. And part of that is reimbursement concern. Most people who fall into the category of needing their lens out have some lenticular change, and I would call that a cataract. But I do try to avoid cataract surgery in people who are not presbyopic. I think the most important thing if you have to proceed in someone who does have accommodation before surgery is just to make sure you’re managing their expectations. I think anyone can deal with presbyopia if they understand that it’s a vision-preserving surgery. But it certainly shouldn’t be a postoperative surprise.

DR KAHOOK: There is a question on whether there were slides on the EAGLE trial. If you go to some of the links that I showed, and I’ll show them before the end of this webinar, we have a lot of videos and a lot of lectures on various topics, specifically EAGLE, will be coming in the next two to six weeks. Will be on the YouTube channel, and you can go to the YouTube channel and see what else is there for now. But we’re definitely gonna put something up about EAGLE and ZAP. Here’s a question I get asked a lot by residents and fellows. Maybe Syril you can answer first. How big should you make the PI hole? It says I’ve done PI for many cases, but I still wonder: How can I be sure that the PI is patent already? So two questions. One, how big do you make it, two, how do you know that it’s patent?

DR DORAIRAJ: I come from a generation — there are cases where I have to do surgical PI. I had to take the patients into the operating room, and you have to do a surgical PI. When we do surgical PI, it’s huge. You can actually see the ciliary body, zonules, everything from there. It typically was done when I was a resident in the 1990s. It’s superior. And after that, I came here and started working with a group of biomechanical engineers, from the University of Minnesota and other places. And then I actually wanted to see if the size of the PI — actually, does it make a difference, whether it’s 200 microns or 400 microns? Where exactly do you place it, whether it’s the extreme periphery or midperiphery? How will it affect the convex iris configuration, opening up the angles? Will it make a difference? No, not really. So even if it’s very big or anything like that, something which has a constant flow, something like 200 microns is sufficient. I’ve got papers on this. You can see — yeah, that’s sufficient. You don’t have to go extremely big, causing all these — even somewhere — more than 200 micron size is sufficient.

DR KAHOOK: This one is aggressive. This isn’t mine, by the way. This is a second pupil, almost. I use this in my LPI lecture, to talk about leaving your signature behind. And sort of what you want it to look like. Sarah, any thoughts on that?

DR VAN TASSEL: They do end up like that, kind of midpupil, in acute angle closure sometimes, because the pupil is so dilated, you’re putting it as far out in the periphery as you think you can, and once the angle closure is broken and the pupil comes down, you’re often surprised that it’s in the midperiphery. But you did that patient a huge favor, so you can’t really worry about that.

DR KAHOOK: You try to do your best. Sarah, you brought up a question to me by email, about a couple of things around ZAP, and I started thinking about the questions. A lot of times, we have these academic discussions about kind of what I have on this slide, how many pulses, what the energy is. What are some of the practical things you have to think about, when you’re seeing a patient in angle closure, you have a first year resident who is calling you, you show up to the emergency room, what are some things that don’t come through academic textbooks or papers or the basic science series from the Academy? Are there any pearls you have for these acute cases where the patient is in pain?

DR VAN TASSEL: I think every patient in acute angle closure — really, I’ll say with an asterisk, but I really mean it — regardless of comorbid medical status has bought themselves 500 milligrams of acetazolamide. Diamox. I typically tell the residents to administer it right away. And you can get the basic metabolic panel if you think it’s medically indicated, to determine if they can have more carbonic anhydrase inhibitor. In some environments, mannitol is easier to get ahold of. You have to be a little bit more careful in older patients with mannitol, because of the risk of subarachnoid hemorrhage and other complications. I think that you really want to try your hardest to hit them as soon as you make the diagnosis, with medical therapy, because I think if you can break the angle closure medically, then you can typically wait 12 to 24 hours to do the LPI, and you will have a much, much easier time, and the patient will be much more comfortable. So I encourage the residents to really stand by, administer aqueous suppressants, get the systemic meds on board, and do their very best to try to break it medically.

DR KAHOOK: Syril, do you ever try and tap these patients?

DR DORAIRAJ: No, Malik. I used to do it, long back. With the idea that the cornea can clear up a little bit and you can have much more clarity and visible… But unfortunately what I’ve realized is: It doesn’t help that much. Over time, I’ve realized the way the anterior chamber fills up, you’re not actually benefiting the patient.

DR KAHOOK: How about for medication penetration? If you’re trying to get the pressure down and the pressure is 60, one of the questions that came in was: Do you try and tap the AC, get the pressure down, so that you get better penetration of your topical medications?

DR DORAIRAJ: That’s a very good caution. I used to do it. All those things, tapping — unfortunately, a year after I came here, everything is a group effort. I have a stand by team in the ER who can take over making the patient stable, in terms of if they’re nauseous, if I have to give them Diamox or mannitol, that’s — the IV line is the one that goes in first. And then I start the topical medication and get them ready for PI. Within a couple of hours, the PI is done. I never tap. I’m not sure about your experience. Most of the instances, getting the pressure down is the main thing we want to accomplish. Getting the topical medications by tapping it is far more riskier. Than giving them something IV, as Sarah was saying, with the Diamox or mannitol. That’s a much faster way to bring down the pressure than by pouring drops, especially in acute angle closure patients.

DR VAN TASSEL: I’ve tapped a few of these.

DR KAHOOK: Go ahead. No, it’s really similar. Actually, there’s a theme to this discussion that we’re having. It also depends on practice, and you just called it, Syril. You said when you moved to Mayo in Jacksonville that you have a team taking care — which is great. From my standpoint here, I think similar things. I’m in clinic. My clinic has a different feel to it. It’s very mature. I’m often in clinic seeing my routine patients, and if something comes in, it’s coming in from the ER. Usually the residents have taken care of it to some degree. But when I’m outside of the country, which before COVID was becoming more and more part of what I do, more traveling and surgery abroad, if a patient comes in, I usually don’t have all the medications that I have in the ER here. So tapping those patients, trying to get them more comfortable, trying to get the cornea to clear a little bit, and trying to get the medications to soak in a little bit better, because there is science behind that, but it does actually help. So in those cases, I will do that. Occasionally if a patient comes in to clinic directly, instead of going into the ER, I will do that to get them comfortable. It’s that relief that allows you to do some of the other things that you need to do. That’s just again: Practice pattern, patient, all that other stuff.

DR VAN TASSEL: I was gonna say the same thing. I agree completely. I would just caution everyone: You do have to be extraordinarily careful. Because these are phakic eyes. With shallow anterior chambers, and you have made the situation suddenly much, much worse if you accidentally penetrate the anterior capsule with your needle. So do use extreme care if you’re in this situation. I know there are people who do this sometimes under a surgical scope with a paracentesis blade. I typically do it at the slit lamp, with a 27-gauge, and I think if you go inferiorly, you can try to use the iris, even in a dilated pupil, to try to protect you a little bit from the anterior capsule. My pearl would be that if you are a dominant-handed surgeon, where you have a strong preference for doing a procedure with a specific hand — for me, in a tough situation like this, I really prefer using my right hand — for a right eye, because the nose will be in your way, you can use a hemostat to bend your needle, so that you can still enter the eye nasally with your dominant hand. I would make sure you’re doing whatever you need to do, ergonomically, to make it as easy and safe as you can.

DR KAHOOK: All right. That makes a lot of sense. Let’s see here. Some of these questions we’ve already answered in one way or another. So I’m sort of skipping over those. But Syril, it says: Rise of IOP after dilation of the pupil. What does that mean to you? How do you handle that? Are you think of it as an actionable thing you should do? Should you do an LPI on that patient?

DR DORAIRAJ: After dilation, especially in an angle closure patient?

DR KAHOOK: Let’s say patient comes in, new to you, you check the pressure, it’s 15, patient goes, gets dilated, you check the pressure for whatever reason, and now it’s 30. How do you think of that?

DR DORAIRAJ: I won’t actually recommend — if it’s an open-angle patient, if it’s an angle closure suspect, the morality of the next step would be entirely different. Just because if you’re dilating in an open-angle patient, if it goes to 10, I won’t do a PI. I would manage them acutely with medication. PI is much more drastic for me, in terms of acute rise of 10 or… I would go one step treating them medically and see if they respond. In a patient, in another eye with hypermetrope, risky angle closure, following up for angle closure, closed-angle, more than 180 degree, I would consider them, once the IOP comes down sooner, to do a PI.

DR KAHOOK: When you have a patient that you’ve done an LPI on, it’s patent, you’re comfortable that the LPI worked, how often do you see that patient back?

DR VAN TASSEL: If they truly have no glaucoma, they were just a suspect, probably once a year. But if there’s any inkling that they have glaucoma, I think it’s a little bit different. I try to adhere pretty closely to severe glaucoma, every 3 to 4 months, moderate, every 4 to 6, and mild every 6 to 12, depending on the scenario.

DR KAHOOK: One question we didn’t get to until now was a question we got before the webinar started. It came in to us yesterday, talking about angle surgery. In patients who have chronic angle closure or any of the angle closures we’ve been talking about, would you think about doing cataract surgery at the same time? Sarah?

DR VAN TASSEL: Can I share my screen, actually? I happen to have a video of precisely this kind of thing.

DR KAHOOK: You should be able to access… There you go.

DR VAN TASSEL: Let’s see here.

DR KAHOOK: You may never give it back. You have control for the rest of the webinar now.

DR VAN TASSEL: So this happened to a patient. You can see her patent PI right here. I finished my cataract surgery, so now her angle is nicely open. And this is actually an excisional goniotomy, with a Kahook blade, someone you may or may not have heard of. Developed an instrument. But I actually love MIGS in these eyes. And sometimes that for me looks like excisional goniotomy. Once in a while, that’s a GATT. I do ECPs in these eyes also. You can see the nice strip of TM. But I have found that these eyes are exquisitely sensitive to angle surgery, in many of these cases. Obviously some of that benefit is from removing the lens, and it would be hard to quantify how much is from lens removal, versus how much is from the angle surgery. But I think it’s ritually satisfying to me that you’re both opening an angle that was previously occluded, and trying to reinvigorate its function. And I think in contrast to primary open-angle glaucoma eyes, where the angle is already open, so there’s only so much you can do to resuscitate it, MIGS might get you a couple points. Maybe a little bit more angle surgery, and an angle closure eye, together with cataract surgery, can really virtually — as we said earlier — almost be curative, in a sense. I love a MIGS in this scenario.

DR KAHOOK: What do you think, Syril?

DR DORAIRAJ: I totally agree. I have a few videos. But anyway, the concept of minimally invasive glaucoma surgery, especially for angle closure, everything MIGS was based — the definition from everything geared towards open-angle glaucoma. But MIGS for angle closure, there are very few. Probably what Sarah showed is extremely important for us to understand. When you’re doing a cataract surgery and if you see anywhere synechiae, and if you — there are controversial reports about doing a goniosynechialysis, but something extra you can do to actually go where Sarah is showing — you’re excising wherever you can see the trabecular meshwork, if you’re going to remove it, it’s going to cause much more different configuration of the angle. Here it’s kind of like when you go there, the root of the iris, once you do a goniotomy in this instance, the root of the iris falls much further. You’re taking out the cataract and also doing goniosynechialysis, opening up where the iris is attached to the trabecular meshwork. Now you’re excising the trabecular meshwork — it’s actually an extra step. Probably you know once there is some sort of attachment of iris into the trabecular meshwork, there’s already a pathology that sets in. In open-angle glaucoma, you can say type 3 collagen and all the things that get into the trabecular meshwork. But in angle closure, it’s an entirely different picture. It’s fibrosis that’s happening, that blocks the extra flow into the Schlemm’s canal. So you’re doing an extra step. It’s far more fulfilling, doing this kind of MIGS, in angle closure patients. You can see the EAGLE study itself, 9%, people who had some synechiae, and if you are going to go one extra step, I would definitely recommend this. And probably two years of data — already I submitted it. It’s collaborative data with one of my colleagues from Vietnam. This is very, very fulfilling. And the percentage of IOP drop, and the stability, it’s almost like… It’s to a state where it’s curable. But one thing is: I would keep them on pilocarpine after this. So you’re touching the iris. It’s much more sticky, compared to the open-angle glaucoma. If I do this on an open-angle patient, I don’t usually keep them on pilocarpine. But these kinds of patients, where I touch the iris, I release it, I keep them for a little longer pilocarpine, or I keep them on a little more steroids, so that they don’t develop a PA immediately after. Though you’re increasing the size of the root of the iris here.

DR KAHOOK: That was one of the questions, the pilocarpine use. So I’m glad you hit on that. Your one-year data on excisional goniotomy in patients that are like this — I mean, this is — whenever I talk about excisional goniotomy, it works in a wide range of patients, but this is one patient population where it’s a home run. If you can take these patients and take the TM out, do goniosynechialysis, chronic angle closure patients tend to do really well.

DR DORAIRAJ: There’s a lot of data, controversial data that came in. Especially even from Singapore, Rahad Houssein’s paper, it’s a prospective study that looked into goniosynechialysis, how they release the synechiae from the angle and going into the next step, it’s all very different. But doing it this way, where you’re kind of accessing much deeper structures, and going into the actual pathology, so far the two-year data really looks good for me. And I think it’s better to kind of push this to angle closure patient, as a surgical option. Especially when they undergo cataract extraction.

DR KAHOOK: I’m gonna ask a question, but Sarah, if you can give the screen to Syril, so he can show some of his iridoplasty stuff… But let me ask a question as you put that slide on the screen. There’s a question here about micropulse laser. Micropulse CPC — Sarah, in your case, do you see any role for it in angle closure?

DR VAN TASSEL: I wouldn’t say no as an absolute. But you’re not really getting at the root of the problem. I tell patients that the eye is a bit like a sink. You have the ciliary body, which is the faucet. And you have the drain, which is the sink drain, and I think fundamentally the only way to get at angle closure is to open the drain, so I think whether there is a role for ciliary body ablation I would say… That is always as a supplement to addressing the drain problem, fundamentally. I don’t do micropulse much, because I haven’t found it to be wildly effective in my patient population. I do a fair amount of endocyclophotocoagulation. Either in someone who is already pseudophakic, or combined with cataract surgery. I do a fair — some CPC. In those eyes.

DR DORAIRAJ: Can I say something on this? Because I do micropulse. I wanted to reflect something on it. As Sarah said, the first thing that we kind of have to focus on — especially in angle closure patients — is to diagnose where exactly the pathology is. And then go and attack it. Whether you’re doing a PI or you’re going to do a lens extraction, goniosynechialysis, or goniotomy, that’s the first step that will be far more beneficial. But if that doesn’t help, doing the next step, before you do a trab or placing the tube in those patients, micropulse may be an option, because your concept here is not like the actual CPC that we used to do, before, where we were kind of ablating the ciliary body. It’s actually — it’s a different mechanism. There is a paper that got recently published by LV Prasad Eye Institute — one of my colleagues did not a micropulse, but like an internal ECP. After the cataract surgery, she went inside the patient, with plateau iris configuration, did an ECP in this patient, and then saw the configuration of the ciliary body completely changed. That’s ECP. But in terms of micropulse, it’s a different mechanism. I would agree you have to go step by step. First you have to go relieve the block here, and then think of other options.

DR KAHOOK: Okay. Do you have a chance to show your iridoplasty? Maybe just walk us through five minutes, maybe, no more than that, so we can get to more of the questions. I’ll call you on it.

DR DORAIRAJ: Okay. I’m not going to… I know this is a very controversial point. I never believed in a lot of things. After I started doing a fellowship in New York City. And also I spent almost 8 years there, doing UBMs, until I realized what really happens in the angle after doing this argon laser peripheral iridoplasty. This is a totally different concept. People argue to an extent — some people say it’s useless. But I still say it has a role. It has a role. Like what we are talking about, with EAGLE — it’s all about the kinds of patients that you’re going to pick up. Say you have a patient who is in their 40s, young women in their brown iris, and when you do an indentation gonioscopy, you have a double lump sign, or you do a PI, they still have positional closure, and they’re progressing with synechiae, and this is where the argon laser peripheral iridoplasty has a role. I used to do it more often. But if the patient is much older, and if they’re developing peripheral anterior synechiae with pressures of more than 50, I would just go with the lens extraction. I don’t know whether I would call it a clear lens, but that would be the next point. I’ve seen patients who underwent iridoplasty, where I would do UBM just to see the peripheral iris configuration entirely changes. Even after doing a PI. The angle doesn’t open up. And so these are the patients, young patients, with the plateau iris configuration, who have some benefit. As you can see, this is much longer. The argon laser that you’re going to use. And the power is around 200 to 500, and the spot size is almost — I give 400 to 500. So I use an Abram lens, and you’re trying to place the burns to the extreme periphery. You go to the extreme periphery, almost like two burns in every clock hour. You give almost 6 in each quadrant, and what you are trying to accomplish is: It’s almost like squishing a Wonder Bread. The burns are so long, it goes to the extreme periphery, and wherever you’re not able to see the angle structure, and you place it, it kind of opens up a little bit. So I don’t know how this helps over time. It’s basically — as we are speaking about releasing the synechiae, or mechanically doing something to open up, for us, the first step is angle closure is an anatomical disease. But there are certain people who might be benefited by it. So that is the concept. People are going to fight. Say it has no role in it. And people who have done it, they say it has a role in it. So it’s all individualized. I’m not going to argue anywhere. But this is something — I don’t know whether this might go out of our practice. Like the way — other options are available for us. But this is something I’ve tried and I’ve done and I’ve seen the angles opening up, in certain groups of patients.

DR KAHOOK: Does Sarah want to argue?

DR VAN TASSEL: I don’t doubt that it has a role. I just haven’t really met a patient yet that I think needed it. In my practice, thus far, at least, most of these patients have either been okay with their LPI or have benefited from lens extraction.

DR DORAIRAJ: So the question now is: Sarah, you have a 40-year-old patient. A female. With onset of presbyope. And has thick brown iris. And you do a PI. Probably when we are residents, we used to discuss something about plateau iris syndrome, plateau iris configuration. Plateau iris syndrome is someone even when you do a PI, the angle doesn’t open up.

DR VAN TASSEL: I think I’m having earphone issues.

DR KAHOOK: Can you hear us okay? She might be muted. Syril, do you have power to mute her? Is that what you just did? I think you’re back, Sarah.

DR VAN TASSEL: I think my earbuds are dying.

DR KAHOOK: Let’s just move on. It sounds like there was — it’s actually very similar to what we discussed with EAGLE and ZAP and some of the others. There’s that potential that some patients might benefit. It depends on your practice. Your practice in Jacksonville might be very different than my practice in Denver. I think that’s kind of the theme, that we have to look at our own practices.

DR DORAIRAJ: It’s also the age group of the patient. If they have a very clear lens, if you see when you do UBM on patients, if you see the configuration of the ciliary body is entirely different, kind of mechanically opening up so that you prevent the progression of angle closure in these patients, before I take them to a clear lens extraction, I would try in young patients like this.

DR KAHOOK: Okay. There’s a question here that… I don’t want to get it into a slippery slope here. But it’s come up a couple of times, by different people here. What is your opinion about iris sponginess mechanism in angle closure? This is a very academic thing that’s discussed in the literature. And maybe Syril iris, primary iris stromal pathology, and its role in angle closure — how do you think of that? I’ve had discussions about this with Deepak Edward, now back in Chicago, and just reading papers about it, to see what mechanism it might actually — how do you think about iris sponginess?

DR DORAIRAJ: It’s probably like you remember — when Harry Quigley gave a talk, the Jackson Memorial Lecture, the concept is: The iris is a sponge for angle closure. Whatever the pathology that’s happening, even if it’s an expansion of the choroid, the fluid from the posterior compartment is transmitted to the iris, and it’s expanding, and it causes the angle closure. So I’ve done a study about — if you take the iris, if you take the iris in an enucleated eye, you take the iris in an enucleated eye and put it in a petri dish, reverse it, it will always go convex. This is published in IOVS. So the concept of blood flow, where it acts like a sponge, to increase the thickness, and then where it becomes much more convex, is not refuted. It’s proven. It’s a biomechanical study that we did. Where you take the iris, a dead, enucleated eye, and then do a complete excision of the iris, and put it in the petri dish, it will go like a convex iris. If you reverse it, it will go like this, irrespective of the flow of the fluid. So the concept of where the fluid — the iris is acting as a sponge, making stromal expansion, giving rise to a convex iris configuration… I have to do more studies on it to understand that concept, but my understanding at this time, whatever is happening in the choroid, if it’s having an impact on the ciliary body and the iris, I need more studies. But I don’t remember anything that can refute it.

DR KAHOOK: Okay. Maybe throw the screen back to me here. And I have a question for both of you that has come up again by two different people, about laser trabeculoplasty. So let’s say you’ve done the LPI. And the angle opens up. Patient has higher pressure. In those patients, do you consider doing SLT or ALT, Sarah?

DR VAN TASSEL: Yeah. In my chart notes, this says sequential LPI/SLT, typically. I would say it’s not the norm, but it happens some in my practice. I think the caveat — more so with ALT than with SLT, but really with both — is you do need to make sure the angle has sufficiently opened, because you can cause pretty impressive PAS. If the angle is not sufficiently open to support SLT. But I do think it there is a role for sequential laser treatment. It can work quite nicely.

DR DORAIRAJ: I agree, I agree, yeah, I agree. It’s exactly the concept of what we are doing, in terms of goniotomy and goniosynechialysis. Where we are thinking the distal collecting channels, even when it’s open, it’s still functional. There was a paper published by Burkhana from Israel, looking into SLT — can you do it in angle closure patients? And it’s very effective. I would say in patients who underwent LPI, and the angles opened up, and if you don’t see much more pigment or peripheral anterior synechiae, I would definitely offer this, and it’s proven.

DR KAHOOK: Okay. Sarah, would you ever do a premium lens multifocal in a patient that you’re going in to operate on like this? Let’s say they don’t have any sign of glaucoma, versus if they have some signs of glaucoma. How do you think of that?

DR VAN TASSEL: I don’t do that many premium lenses. So I’m not the world’s best authority on this topic. I will say that hyperopes tend to be the easiest to please with multifocals. You can just almost do no wrong. And so I think it does come up now and again, someone who had an occludable angle but truly has no glaucoma, who is hyperopic, is interested in a multifocal, and I do not deny them that opportunity, but I have an absolute no tolerance policy for multifocals in anyone with glaucomatous disease, and I very often steer patients away from them regardless.

DR KAHOOK: What do you think, Syril?

DR DORAIRAJ: Why not? So if you have patients — my concept of what to offer to this patient entirely changed. Because it all depends on your patient population. I have patients who will come, who want to do things the next day. Yesterday, I did six femtos. People you suspect, without any angle closure, peripheral anterior synechiae, you don’t have to do a goniosynechialysis in them, hypermetrope, I did femtos on them. My colleague does ED IOLs and also multifocals. If the patient has glaucoma, it’s a different concept. I don’t recommend that. But patients who are hypermetrope, who are suspects, and optic nerve is healthy, baseline, everything is fine, young patients, if they want, I just tell them everything. The problems that they are facing right now. And I do have a huge chunk, probably — I don’t do that many femtos. Probably 15 to 20 femtos a month. Most of them, hypermetropes, angle closure suspects. They take premium lenses.

DR KAHOOK: You have a unique practice, Syril. 15 to 20 femtos is very unique across the US. It’s very high volume surgically and very unique. You’re adventurous and you’re a great surgeon and your view is a little bit different. All of the challenges for me — all the debates we’ve had at Academy, AGS, the international meetings, where you have one surgeon saying I’ll never put in a multifocal and the other saying you have to put in an multifocal. I was on the side of not using multifocals to patients who might progress to visual field defects. Now that debate is different, because we have lenses emerging on the national market, just looking at different ways to get enhanced depth of field, there’s a new lens that made its way to Canada, hopefully to the US soon, Vivity from Alcon. Not putting in a plug. No financial interest in that. But it’s a different mechanism for getting depth of focus. We have to start asking these questions more and more. Are we doing our patients a disservice by not giving them a premium lens, if we’re constantly thinking about a ReSTOR, let’s use another Alcon product on the other side of the debate, maybe don’t use that, because of the way the optics might work. In my practice, I don’t do multifocals. We do torics. I’m not a heavy user like some of my other partners. But I think that’s the right thing to do, at least to be offered to the patient. These debates will continue. The better we get at the glaucoma part and the more comfortable with that, the more we’ll start thinking about refractive and making sure they can see better and better. We’ve answered the majority of questions. We’re getting repeat questions that we’ve already touched on. I’m gonna start closing the webinar here just by saying a couple of things. We can continue to answer questions through — please go to the Cybersight website. You’re gonna see this lecture posted. There’s a system for talking to mentors. On the Orbis website, where you can ask questions. I’m on that, so you can certainly reach out to me, and ask me some questions. This YouTube link — it’ll take you to a channel where I just populate all of the lectures, and you can ask questions within that. And if there’s anything interesting for Syril or Sarah, I’ll get them involved in answering some of those questions as well. Because there might be some stuff that you didn’t want to ask on the Q and A or before the meeting. And please keep asking these questions. I’d also personally love some feedback on the Point-2-Point feedback. We did this for two hours. Maybe that’s a little too long for some, not long enough for others. I’d love to hear — for Orbis, let them know the feedback on the length and the panel discussion. Maybe we can modify it. The next Point-2-Point is going to be surgical, it’s gonna be about tubes, so please send some questions in. It’s gonna be heavily surgical, some videos, and just talking about different techniques for glaucoma drainage devices and pearls for practice. I’m gonna close off by saying thank you. I know you’re busy, from a practice standpoint, it’s not easy to take a morning off. Sarah, I didn’t invite you. I begged you to do it. And Syril, thank you. I know how backed up you are because of COVID issues. So thank you so much to both of you. I know the audience is sincerely thankful for your time as well, and I owe you both one, so I can’t say no to whatever you invite me to next. So thank you again to Orbis, to Cybersight, to Lawrence for helping us put this together, and to the audience, thank you for taking the time, and please do reach out with questions and comments, and we’ll see you back here at Point-2-Point, December 17th. Thank you.

DR DORAIRAJ: Thank you, Malik. Thank you, Sarah.

DR VAN TASSEL: Thank you, everyone. Take care.


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July 10, 2020

Last Updated: October 31, 2022

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