Lecture: Microinvasive Glaucoma Surgery: Successes, Challenges, and Lessons Learned

During this live webinar, we will discuss data regarding different Microinvasive Glaucoma Surgeries (MIGS) when it comes to efficacy in terms intraocular pressure and medication burden. We will also discuss the concept of MIGS Plus, sMIGS (single MIGS), and cMIGS (combination MIGS) with patient examples, challenges and possible complications.

Lecturer: Dr. David Sola-Del Valle, Massachusetts Eye and Ear, Assistant Professor of Ophthalmology, Harvard Medical School, USA


Good morning, everyone, at least here in Boston. It’s a pleasure to be here again. I was just here I think three or four weeks ago giving another webinar. Today, the topic is a little different. Last time we talked about new therapeutics and today it’s more of a surgical webinar. And, specifically, I’ll be talking about microinvasive glaucoma surgery, successes, challenges and lessons learned. For those who weren’t here a few weeks ago when I was here. David Sola-Del Valle. Dr. Sola is how my patients know. I’m at mass eye and ear and a professor at Harvard Medical School. It’s an honor to be here to give you a webinar. And I hope we’ll all learn a lot together this morning. I do have one financial disclosure that is relevant to the webinar. Back in 2021, I was a lecturer for the XEN Gel stent for 3 months. This is the outline for the talk this morning. First I always like to explain what the terms are. I find that now that there’s so many different options in the MIGS realm, finding a vocabulary we can all understand is important and it’s honestly been one of the main things I focused on with me research in the last five years. I’m going to start with that, what is MIGS, why do we do MIGS and other definitions that may be helpful for the webinar today. Then I’ll talk about classic MIGS and I picked a few that I thought were interesting to discuss and I’ll share some data about them. And then we’ll talk about what I term MIGS plus and we’ll get into that in a second. And I picked some specific examples in the realm of MIGS plus. Then we’ll talk about the idea of combination MIGS or C MIGS and single MIGS or sMIGs. At the end I hope to go through cases to illustrate how MIGS can sometimes be extremely successful and also challenges you can encounter with MIGS and I’ll end with some of the things I’ve learned over the years doing lots of MIGS here in Boston and Massachusetts. As I said, I think understanding the definitions of what, when we say MIGS and when we say a special type of MIG, for me it’s good to understand what are we talking about. I like to start with the classic definition of MIGS which was coined by Amid in 2009. When we talk about MIGS we talk about Ab Interno biocompatible procedures that create minimal trauma and have a great safety profile and lower IOP and are rapid and easy to perform and have a fast recovery for the patient. In this group, we have the iStent, the iStent Inject, iStent Infinite, the iAccess and the Hydrus and the Ab Externo XEN Gel. The idea is you’re not disrupting anything in the eye. It’s a great definition but it’s limited. That is why I’m a fan of using this other term called MIGS Plus. In my mind, MIGS Plus is a more encompassing term. And it basically means nontraditional glaucoma surgery, i.e., does not include trabeculectomies and tubes, glaucoma drainage devices, but it’s smaller procedures that still have a great safety profile, still lower IOP and medication burden, are still rapid and easy to perform with a relatively fast recovery for the patient. But they do allow a little bit of trauma to the tissues in the eye. And this is the group that includes the goniotomy, the ECP and the micro pulse and open Xen Gel stent. I always like to start with this slide when giving general MIGS presentations. There is a lot of controversy, my older colleagues are a little reluctant on MIGS because there is not a ton of randomized clinical trials for these. But I still think they’re important and have an important place in glaucoma treatment, otherwise, I wouldn’t be here today spending an hour with you talking about MIGS. But it’s good to understand why reducing medication burden and IOP is important. The first thing is medication adherence. We all know this but there is data behind how problematic this is. In the United States 27 percent of prescriptions across all medications are filled, are not filled even after they’re prescribed. So up to almost 1/3 of medications the doctor sends them to the pharmacy but the patients do not pick them up. In the glaucoma realm, up to 50 percent of glaucoma patients admit to not being complaint with the medications they’re prescribed because they’re skeptical about the glaucoma diagnosis. This is difficult in the glaucoma world. Glaucoma is a sneaky disease, a silent disease and yet you’re telling people to put medications in every day and it’s tough. It’s important to know the barriers to adherence. This is the most problematic percentage, 80 percent of people who are glaucoma and are prescribed medications admitted to deviating from the medication regimen. Again, medication non-adherence is a big problem and I think that’s where MIGS can be very, very beneficial, especially if someone is undergoing cataract surgery and is on medication, et cetera. And we’ll go over that in the talk. The other thing I want like to emphasize is every point matters. I heard older colleagues saying it only lowers IOP 2 mm of mercury. Right, if it’s 40 or 50, 2 mm is not going to make a big difference, but MCD showed that every point matters. In some patients it can make a big difference. There is good data now to show that cataract surgery lowers IOP but it’s usually not enough for glaucoma patients. And MIGS can be combined with cataract surgery. Cataract surgery can lower IOP by 15 percent. The other thing about cataract surgery lowering IOP is it doesn’t last long. Usually by one or two years it’s down to 9 percent or lower. The good thing about MIGS is it’s relatively fast recovery and relatively easy to do. And there is something that never fails. When I tell a patient that I’m doing minimally invasive surgery in their eye, they love that term, minimally invasive. That is another reason I think MIGs is the way of the future. I wanted to present a few review articles because I only have one hour today. And MIGS has exploded in the last ten years at least. In fact, I’m reading here this article, it has exploded over the last 8 years with MIGS procedures of at least 400 percent increase in the United States. There is no way in one hour I can talk about every iteration of MIGS and every single study. So my lab group has put together a series of review articles that are open access if you have PubMed and Intermed, you should be able to get them. And a lot of data I’m presenting comes from them. It’s not all the data included in the review articles but basically, if you want to go back after the lecture and read these articles, you’ll get more details. The first one is the general MIGS review article we published in 2021. It basically goes over the main MIGS and the data remind them. We recently published an article in 2022, talking about the idea of combined microinvasive glaucoma surgery and the data behind it. In this article we came up with a set of definitions. When I say phaco, I mean cataract surgery. When I talk sMIGs that is one type of glaucoma surgery with cataract surgery. When I talk about cMIGS that is two or more microinvasive invasive glaucoma surgery. Standalone MIGS is MIGS without cataract. The ICE and D-ICE and inject. And ICE-1 and ICE-2 and PECK. IStent cataract ECP. A combination of MIGS. And ICE1 we don’t use in the U.S. because we moved on. And I anticipate in the future we may do the ICE3 procedure. We’re not there yet. Then there is a PECK procedure and that’s a term I coined in 2020, it’s phaco ECP and Kahook. The last review article I’ll be referencing today from my lab is this one from 2020. We reviewed the evidence behind cyclodestructive procedures in the treatment of glaucoma. This is relevant for the ECP. Classic MIGS, the first is the iStent inject and I’m grouping that with iStent inject W. I think most of us have moved onto iStent inject W. It’s a tiny device. You can see it has four clicks to make it happen. It’s relatively easy to use. You can see the trocar here is very thin. You have to be careful not to bend it and I’ll show videos in patients I’ve used this. This is what it looks like in the end. You have the injector with two stents. You try to put them as far apart as you can. At least 30 or 60 degrees apart. You’re bypassing increased TM resistance and provides a pathway into Schlemm’s canal. This is from the review article that I highlighted. It’s a table of the data from 2014 to 2020 talking about ICE and inject. The IOP reduction goes from 1.6 to 12.2 mm of mercury while reducing medication burden from 0.5 to 2.4 medications. And one thing I will say, it’s always hard with the data to tease out how much of the IOP reduction comes from phaco alone, from the cataract surgery alone versus the iStent portion of the procedure which is why there are some studies here that looked at ICE and inject alone which unfortunately is not approved in the U.S. But it is approved in other places in the world. And there was a phaco arm. The ICO inject is better than phaco but it’s controversial how much. So who are great candidates for ICE and inject and a lot of these ideas are going to be repeated throughout the talk. In general, the great candidates are POAG patients from mild to moderate. Patients with a visually significant cataract but are on stable medication, stable disease. I always say and this is controversial, if you have a patient with a cataract on latanoprost or timolol, it’s a missed opportunity not to do MIGS at the same time as a cataract. Especially something like the ICE and inject that can stop the medication for 2, 3, 4 years and lower the IOP further. I’m a big fan to include a MIGS when doing cataract surgery in patients who have stable disease. We do have to admitted, ICE and inject is not as good as other types of MIGs and you can get a modest IOP reduction. You have to be careful with patient selection. If you only want a modest IOP reduction and medication reduction, the ICE may be good. In general, I try to avoid severe glaucoma patients but if you’re careful. If they’re vehemently opposed to surgery especially if they’re stable on medications, you can try it. And sometimes you do get a little bit of success. And then the cMIGS idea, I’ve become a big fan of combining different types of MIGS. I feel like each MIG gives you one or two mm of mercury and if you combine it you get four or five. Especially for the sicker patients, combining MIGS can be important. I avoid MIGs in patients who are rapidly progressing. Patients, I said this, patients with very high IOP, we have to be realistic, MIGS is not going to drop a patient from 40 to 15. It’s not going to happen. It’s not great for patients with high IOP. Same thing with patients who have angle dysgenesis where the TM is not easily visualized or patients with active neovascularization or expensive PAS. The PAS can be, sometimes you can work around the PAS. Sometimes, many times I will go into the OR and in clinic I did a notice a PAS that is significant. And if it’s a dry adhesion, I can still do it. It’s not that PAS is a deal breaker but if there is a lot, if you can’t visualize a TM, you shouldn’t be doing the angle procedure. In general, for MIGS, single digit IOP requirements. If someone is progressing at an IOP of 10 or 11 on five medications and you’re trying to get them between 5 and 9, 99 percent of the time MIGS is not going to do it. In terms of postop care, possible complications with the ICE and inject include stent mal-positioning, hyphema. This is a question I get a lot, when do you stop the medications. In lower risk eyes I try to stop them right away. Especially if they were stable before surgery. The point of MIGS is to stop the medication. In higher risk eyes, sometimes only I use one and keep latanoprost. The other key thing to remember with MIGS, you’re not going to get to a new steady state for 6 to 8 weeks or 4 to 6 weeks. While they’re on steroids, you don’t get the final results. Obviously, if you’re doing cataract surgery you have to keep them on steroids for at least a month. So keep that in mind. In general, I try to stop MIGS right away so by the time they’re off steroids I can see what the response was. A lot of patients do really well and I keep them off the medications for a while. I’m not going to say too much about iStent infinite because I haven’t had the pleasure of using it. I’m looking forward to it. It’s FDA approved in the U.S. The main reason it’s not widely available is reimbursement issues. Because MIGS has exploded 400 percent in the last 8 years, I think Medicare and the insurance companies in the U.S. are really trying to decrease costs and thing this is the perfect example of a situation where I wish there wasn’t so much oversight because I think it’s a great thing for patients. But anyway. I’ve not had the pleasure of using it. I’m looking forward to it. We’re working on reimbursement issues here at mass eye and ear at the moment. I hope to offer this soon to patients. This is FDA approved as a stand-alone MIGS which ICE and inject is not. So that’s exciting. I do think two stents work better than one and three stents will work better than two. There are some articles showing that very clearly. And in severe glaucoma patients, I think this will be — I saw a great presentation at AAO last year showing data on ICE and severe glaucoma and it works. I’m excited to try this and combine it. There was ICE1 and now we’re doing ICE2 and I’m looking forward to doing ICE3 which may end up being a really, really powerful procedure. The iAccess, very controversial as well. It’s a small device that makes small goniotomy in the TM. I’ve been doing a lot of combined procedures. It’s almost part of C MIG. I put the two ice and injects and access in between on each side of the ice and injects. We just submitted an abstract and I don’t know if it will be accepted. It was a small case control study because I haven’t done a lot of these. Based on the little information we have, we did show that the iAccess can decrease medication burden more than doing the phaco ICE inject by itself. I think we need more data on iAccess. I think it’s a procedure that doesn’t cause a lot of hyphema. I think the jury is out but I’m excited to see what the data shows over time. This is the first question of the day. To keep you guys engaged and see if you have learned something. Which of the following is true regarding the iStent inject? It’s currently approved in the U.S. as a stand alone procedure. B, angle closure and neovascular glaucoma patients are good candidates for iStent inject implantation. Phaco and iStent inject produced an additional IOP and medication reduction over cataract single alone or, D, adverse events are higher after phaco iStent inject than cataract surgery alone. I will give you 30 seconds for your answer and then review with you guys. Great. 62 percent of you got the right answer. Quickly, unfortunately the ice and inject is not approved as a standalone procedure. I said the ICE infinite angle closer is controversial, but those with active neovascularization are not a good candidate in ICE in general. We have good data from a clinical trial using the ice and inject lowers the IOP and medication burden more than phaco alone. It’s a very safe procedure. >> Now I’m moving onto Hydrus. It’s a popular procedure, there is a lot of great data supporting it. It’s about 8 mm in length. A scaffold 7 mm of the scaffold is in the trabecular meshwork. It’s made out of this nickel titanium aloe. It fits the curvature without obstructing of the TM and without obstructing the collector channels. And basically the idea is you bypass trabecular resistance. And again, this is from a review article, the IOP reduction goes from 1.7 to 8 mm of mercury and you can reduce medications from 0.4 to 1.7. There is a clinical trial that shows that Hydrus does decrease IOP and medication burden over phaco alone. One of the hardest things in the MIGS world is deciding what MIGS you do for what patient. There is a lot of work we need to do on this patient. This is one of the main research interests of mine and my lab. This is a paper that compares studies showing that one micro stent is getter than two iStent. We know it’s at least the same or better. Depends on the study. This was a well done study. Randomized clinical trial. You can argue that the Hydrus is better than the iStent inject but there are studies that show they’re equivalent if not better than the Hydrus or the iStent inject. This is a study, and I had the pleasure of seeing Gus’s presentation at AAO last year. He was in the same talk poster session as our XEN Gel. And he presented compelling data. To my knowledge this is the first time that a MIGS device has visual field data backing it up. Showing that cataract surgery combined with Hydrus had significant preservation in glaucoma patients. This is one of this things that MIGS devices lack, they don’t have the visual field data to back them up. This is the reason that we’re doing this. We’re decreasing IOP to preserve the visual field. This is one of the reasons that Hydrus use has skyrocketed. Which of the following is false regarding the Hydrus micro stent. Bypassing the TM is the main mechanism of action of the hydrus micro stent. Hydrus is the only MIGS device with proving impact preventing visual field loss. Hydrus is currently approved in the U.S. for mild to moderate POAG. Or hydrus is less efficient at IOP medication reduction than the iStent. We want to know which is false. Three of the statements are true and one is false. Yes. The answer is D. 42 percent of you got it right. And this is talking about the compare study that showed that hydrus is better than ice and inject. There are other studies that show they’re equivalent but we know it’s not less efficient. That is why that is false. C is correct. Hydrus is currently approved in the U.S. only with cataract surgery in mild to moderate glaucoma patients. I just told you of the study showing that visual field is, in fact, visual field progression is prevented by hydrus and to my knowledge that’s the only MIGS device that has that data. And bypassing the TM is the main mechanism of action of hydrus. So the first three were correct, the last one is the false one. Now I’m going to delve into the MIGS Plus arena. The classic example is the Kahook dual blade. I’m a big fan of this in general and it can be done with three devices. The Kahook has a foot plate of 230 microns. This is the data de-hind the dual blade. Lowers IOP between 2.9 to 12.7 and reduces medications from 0.5 to 2.2. The biggest issue with the Kahook especially when you’re trying to argue the point that conferences or with colleagues, goniotomy has been around for a long time. There is not a large clinical trial that compared phaco to phaco Kahook. I think that’s one of the biggest issues with the Kahook blade especially when trying to convince another colleague that the Kahook is amazing. I think there is good retrospective data showing it works and lowers IOP and decreases medication burden well. This is one of the examples where a Kahook blade can be amazing. I used it in angle closure glaucoma patients. If they have PAS, I use the — to break the PAS and the blade to open the drainage system. The other great thing about the Kahook blade, I’ve used it successfully in advanced glaucoma patients not just angle closure but advanced glaucoma patients. Great candidates. OHTN mild to moderate glaucoma. The one thing I will say about the Kahook dual blade is you will get more hyphema than classic MIGS. That’s why it’s MIGS Plus. You’re disrupting the architecture more. Because you’re doing an ab interna trabeculectomy, you will create more of a hyphema. I try to stop blood thinners in patients undergoing this. And I try to be selective with the patients. If a patient is high maintenance and they’re not going to toll rat a hyphema for one to two weeks, blurry vision, this might not be the best surgery for the patient. But outside of that, it has a similar profile to other MIGS. The blurry vision, the hyphema is the main complication, up to 40 percent. You can get corneal edema and rebound iritis. If you’re not careful or have trainees without a lot of experience, you can actually cause damage to the iris. So you have to be careful. We just submitted an antibody tract to AAO showing that PCO rates are higher when you have combination MIGS versus phaco. So it might be something we’re telling the patients in the future is you have a higher risk of PCO which has an easy fix we should talk about it. The steady state is 4 to 6 weeks after the steroids are stopped. There are different ways of doing this. I fell in love with this device, SION. It’s smooth. For those who do research, it allows you to collect the trabecular meshwork which I had a hard time doing with the Kahook dual blade. I still use the Kahook but this is a relatively new device that I have enjoyed. It’s very smooth. Not a blade. And you can actually collect TM if you’re doing research. The TrabEx is the other one. This is what it looks like. I haven’t used it yet. One of the things that you can do with the TrabEx is add IA to it. And sometimes when you’re doing the Kahook dual blade you get a hyphema immediately: It could be a good device. In the future this depends on cost. I think it would be interesting to do a trial when you compare these and considering in countries where, which I know a lot of you are in countries outside of the U.S. where these devices can be expensive. Including an arm where we do a cystotome and just a needle of the BANG procedure as some call it. And one of the main things that I think the MIGS world needs is more comparative studies to help you decide which is the best MIGS for each patient. That is one of my passions and the thing my lab does a lot of. This is a paper that we published comparing Hydrus to Kahook. In our experience in this study here at mass eye and ear there was not a big difference between the two. That is why as of today, even though there is great data behind Hydrus, I have stuck to do phaco Kahook for my patients. Because you’re not leaving a device behind. It’s faster to do in my opinion to the Kahook blade and Hydrus and it seems like you’re getting the same IOP and medication burden reduction. This is a retrospective study and there are limits to it but it’s one of the reasons I’ve been doing more goniotomies than hydrus in my practice. Which of the following is false regarding the Kahook dual blade. Hyphema is the most common complication. The KDB is currently approved in the U.S. as a standalone procedure or in conjunction with cataract surgery. The KDB device is equipped with a tissue collection window. Or the KDB is contraindicated in patients with active neovascularization or angle dysgenesis. Which one of these is false? Three are correct and one is incorrect. Hyphema is the most common complication. You can do KDB as a stand alone or in combination with cataract surgery and I would not do it in patients with active neovascularization because you can end up with an — high FEMA. The device is not equipped with a tissue collection device. Okay. So a little about ECB, I’m a fan. You can directly visualize the cellular processes and shrink them with a laser. Most studies that have been done have included mild to moderate patients and show that you can decrease pressure from 3 to 11 mm of mercury or 11 to 38 percent. I think there’s good data and one of the papers I cited here is from Dr. Lynn who is my colleague here at mass eye and ear showing that phaco — I find that not only do you decrease fluid production but you’re rotating the iris away from the TM and opening the angle. Many angle closure patients I love doing ECP. There is good data that appears to be effective in all stages of glaucoma. There’s also, I’m citing data here where phaco in angle closure patients where you break the synechiae is just as effective. That is something that should be studied more. And a study citing they did a phaco Trab versus ECP study and in that study they showed they were both effective in lowering IOP and medication. The great candidates, again, a lot of these things I have talked about for KDB and ice. Pseudophakic patients. You can’t do ECP unless you remove the lens. That is one thing to keep in mind with ECP. But outside of that, it’s the same thing. Failed incisional surgery. There are studies that have shown if you fail Trab or a tube, you can do ECP and it works. I would be careful with patients that are prone to inflammation. In terms of postop care, possible complications, the main ones are rebound iritis and CME up to 13 percent. When doing ECP you want to inflate the sulcus with Healon and shrink the cellular processes. When I do ECP, I try to give them solumederol and a Medrol dose pack in high risk patients to make sure they don’t get inflamed. And similar to other MIGS, there is a new steady state once you’re done with the steroid taper. This is an interesting study my lab just published I think a month ago. We compared phaco ECP360 to phaco micro pulse. And showed they were at least equivalent. Maybe phaco micro pulse was slightly better. We need more of these studies where we compare things and try to determine which patients do better with which procedure. So which of the following is true regarding ECP. A single incision is enough. Hyphema is a very common complication encountered after ECP. ECP is contraindicated in patients with angle closure glaucoma. Or ECP appears to be effective in all stages of glaucoma. Again, we’re looking for which one of the four is true here. I’ll give you a few seconds to answer. Perfect. Most of you got the right afternoons, ECP appears to be effective in all stages of glaucoma. You cannot do 360 degrees with a single envision. My good colleague routinely does 360 but she does a second envision. You have to. With one incision you can do 270 but not 360. I said iritis is a common complication, up to 13 percent. Hyphema you can get it but it’s rare. I just said ECP works great in angle closure glaucoma patients and it’s one of my preferred MIGS. The correct answer is the last one. Briefly I will talk about XEN Gel stent. I’m a big fan. There are four ways of doing it. You can do ab interna or ab extern know. In the U.S. we only have the 45-micron lumen. And it’s approve for refractory glaucoma patients. I typically, and the IOP reduction can be anywhere from 4 to 18 mm of mercury and decrease the medication by 1.6 to 2.6. But I found and I wanted to show you the video of how I do the XEN. The way that is most effective is ab externa. I mark 1.5 to 2 mm and inject the iStent. I published this in the American journal of ophthalmology case reports. I put a suture to make sure the stent is lying flat. By doing this, I avoid scar tissue clogging the stent and I had great successes. I enclose the conjunctiva over it. I found doing it this way I have the most success. We’re in the process of trying to publish articles comparing this to the closed and the trabeculectomy. Now, a little about combination MIGS. Again, these are the ones that are combining more than one MIGS with cataract surgery. The most classic combination is the one that enhances flow through the trabecular meshwork while reducing the aqueous humor production. This was an article last year that is now in print and we showed that adding the additional MIGS can decrease medications and additional .2 to ‘ 7 medications over single MIGS and decrease IOP6 to 45 percent more over single MIGS. In some patients this can be significants. One paper that we published is comparing PECK versus ice 1. We don’t do ice 1 anymore. But the PECK procedure can give you up to 5 mm of mercury in reduction at one year while decreasing medications up to 2, 1.6 to 2. And I find this amazing because in the PECK procedure you leave nothing behind. No sutures. And you can still decrease IOP significantly while decreasing medicine burden. For mild to moderate patients the PECK procedure can do wonders. All of the MIGS data and I said limitations of the current C MIG study but this applies to the sMIG studies in general. When it comes to MIGS, this was published in 2019, only 45 percent of them follow the stringent world glaucoma association guidelines for surgical trials. When we look at the MIGS data we have to keep this in mind. It’s a limitation of the MIGS data. A lot of the studies are retrospective and do not follow the guidelines. It’s really hard to do. It’s hard to do a randomized clinical trial. It’s expensive and hard to control the variables. It’s something we have to — I keep publishing the data I have and we have to. We need some data to guide us. But we have to keep in mind that these are limited by this. There is usually small sample sizes and relatively short followup. When talking about cMIGS and combination MIGS and comparing to sMIGs, we have to work about the bias. Who are we giving combination MIGS to. It’s usually sicker patients and it’s hard to work around that bias. Just something to keep in mind when you look at the MIGS data. Let’s start with the case presentation. I have case No. 1. 77 year-old woman complaining of difficulty driving at night. Referred to my clinic for evaluation. Acuity is decreased. Has pseudo- exfoliation. The OTC is a little on the thick side but not too bad. The visual field, scattered nonspecific defects. Mild PHG. Pseudo-exfoliation glaucoma. The IOPs are 14 and 16 on timolol. The question is what do we do for this patient? In summary, 77 year-old woman complaining of difficulty driving at night with mild to moderate pseudo-exfoliation glaucoma would be happy to come off the timolol but it’s not a deal breaker for her. What would you do. Cataract surgery alone, with one MIG, cataract surgery with two MIGS or a Trab or tube. Observe and tell her she doesn’t need surgery or other. For the next three questions there is no right or wrong answers: We don’t know. Phaco with one MIGS. Good. That is what most people would have done. I was more aggressive because I like to — even though it was not a deal breaker to come off of the timolol, I like to stop medications if I can. So I decided to actually do a combined procedure. So I did the cataract surgery. I didn’t include that portion of the procedure because it’s a MIGS talk. I finished the cataract and put in the lens and inflated the sulcus with the Healon. I’m trying to shrink the cellular processes here. I’m doing the ECP portion now. I try to get to 270 degrees. I do two coats. And then I’m doing an iStent inject. In addition to doing the ECP, I put in two stents and you’ll see me doing that right now. And this is the ICE-2 procedure. I decided to do the ICE-2 procedure on her. I figured this gives the best shot of stopping the timolol while keeping the IOP well controlled. And relatively simple procedure. And this was the final result. She ended up getting ice 1 in one eye. That was a video of the left eye with ICE-2. She has excellent acuity. Her pressures are 10 and 12 off medications. For me that was great. I was very happy I did the cMIGS procedure. If you said 1 MIGS, I get it. That is what most people would have said. I want to show you the power of cMIGS. It cannot only lower IOP but stop the medication. You have more guarantee of that. Depending on the patient it’s something to consider and also depending where you are in the world. This is case 2, 76-year-old man referred by a retina specialist for high IOPs. I followed him for a year. Tired of the glaucoma regimen but surgically avers. Complaining of difficulty driving at night. Focusing on the right eye, the OCT was thin. On Vyzulta, everything. Acuity was 20, 30 but BATed to 20/70. This is the field for the right eye. There is some damage. In the moderate to severe situation. Another PXF patient, these can be challenging. So for that eye, 76-year-old with moderate to severe pseudo-exfoliation glaucoma in the right eye. Stabilized on five agents, keep that in mind. Complaining of difficulty at night. What would you do? Would you do cataract surgery alone, one MIG with cataract, two MIGS with cataract. Phaco with trab or tube, observation or other. I’m curious what you would do. No right or wrong answer, I’m just trying to have a discussion. Phaco with Trab two. I get it. I think most of my older colleagues would have done that. He is on five agents but I decided to actually do a PECK procedure. Basically, this video is shaky at the beginning. I had done the cataract surgery and I’m trying to inflate the sulcus. I’m about to see the ECP part of the procedure. Let me see if I can — it’s shaky as well here because I do let my trainees do a lot in the OR under my direct supervision. Here shrinking the ciliary processes and this trainee is doing a great job but she is still learning. That is why the probe is going up and down a bit. We finished the ECP and I’m going to fast forward a little bit in the interest of time. And then we tilted the head and using this prism here I’m going to go in with the Kahook dual blade and I do the inside out fashion with the Kahook. I start inside and go out and turn and go the other way. I feel like I get more clock hours out of it. You can see there is a hyphema forming that is expected and normal. We were in the right place so that is great. I decided to do a PECK procedure and one year out and time will tell, I saw him recently, he is now 3 years out from this procedure. Visual acuity is 20/30, 20/25. He has a little macular degeneration in the right eye. But the pressure in the right eye dropped to 11 and the regimen was simplified from five things to just two. And he was very happy. For him it wasn’t a big deal because for the other eye he was still taking meds and didn’t want surgery in the other eye yet. This was a huge success. Sometimes, especially combination MIGs and the PECK procedure can do wonders. I find that the goniotomy can do wonders for these patients. Case No. 3, 87-year-old man self-referred for a second opinion. He went to another doctor and told that he should get a phaco Trab in both eyes. He wasn’t happy with that. He was an economics professor. He had severe glaucoma in both eyes. This is severe glaucoma. I mean, I think most of us in our right mind would have done a phaco trab but he didn’t want it. He asked what else to do. Bated to 20/60. Was on latanoprost and I decided and his pressures were 19 and 12. After discussing with him, this is the last question, you have 87-year-old severe mixed mechanism glaucoma complains of difficulty driving at night. Surgically avers. What would you offer him? Cataract surgery alone, one MIGS, two MIGS, tell him that other doctor was right, you should be getting a phaco trab, observe him or other? What would you do for this 87 year-old. Good. You guys, and I get it. Some of you would say stick with what the first doctor said. Do a phaco trab and you would be right and many people would agree with that. A lot of you said two MIGS which is great. I’m throwing you a curve ball here, for this patient I decided to do phaco micro pulse. I found and this goes to that article I showed you comparing phaco 360 to micro pulse, a phaco micro pulse can do wonders for some patients. I did phaco micro pulse in both eyes and 90 seconds per hemisphere. 27-milliwatts. Slow sweeps. The great thing is that he did great. The acuities were 20, 25. Pressures were 11 and 11. But he did great. Unfortunately, he did pass from CHF, cardiac failure. But his wife wrote me a very nice letter thanking me for his surgeries and said he saw well to the very end. I saved him a trab in both eyes. Sometimes you have to think outside of the box and a phaco micro pulse can do wonders for a patient. I’m running out of time. I have three more cases. I showed you three successes and I’m going to show you now three — maybe not — I don’t want to say failures but not successes. This is in the lesson learned category. 56-year-old man with narrow angle glaucoma. The pressure is not well controlled despite 4 medications. I decided to do a phaco ECP in May 2018. Initially I was able to drop the pressure to 12. I had to add back on the medications. The field worsened. This is one of the lessons learned. He has a — was on six medications. Yes, he had narrow angles and I was hoping the phaco would do the trick but it didn’t. And it happens sometimes. Sometimes MIGS doesn’t cut it and that is part of what you need to do when consenting the patient is prepare them for the possibility of failure. That should be the concept of any glaucoma procedure but in the MIGS realm. The patient understood. And I saw him a few months ago and he is doing great. He is still 20/25. Case No. 5. I have this 61-year-old African American man, moderate to severe POAG. Very long story. Worsened visual field despite 5 medications. 6 failed surgeries. He developed double vision and I had to remove the Ahmed. Did micro pulse, did nothing. And then I did a Baerveldt but he developed a cataract. I did a phaco ECP in July 21. The pressure improved but he was 11 on three medications which was a huge success for him: He developed CME. This is a case where you have to be careful of patients with inflammation. I proceeded with the ECP. Tried to hit him hard. I used Durezol after surgery and despite that, this happened. Something to keep in mind. If someone has a history of CME and predisposed to strong inflammation, ECP may not be the best procedure. I will say he is doing well. We started injecting him and he is happy. This went away. That doesn’t mean that CME is going to go away but it’s something to keep in mind. And the last case, 67-year-old Hispanic man, narrow angles, elevated IOP. OCT normal. Elevated IOP of 23. Difficulty driving at night. I did a phaco ECP in July 2021. I’m giving with the cases, I’m a teaching institution at Harvard. This particular resident when he was inflating the sulcus, injected too much Healon and created this. I had to do a YAG capsulotome. The patient doesn’t notice but it doesn’t look pretty when you look. So you have to be careful especially when teaching residents. These things can happen. I’ve learned that controlling inflammation early is crucial. You have to select patients with mild to moderate glaucoma for best success. I would avoid doing MIGs in general with patients with very severe glaucoma or require single digit pressures. Watch out for hyphema. Coach patients through it. Especially mono-ocular patients or patients who can’t tolerate blurry vision. Consider combination MIGS: I really think that’s the wave of the future in MIGS, is trying to combine different MIGs that are still not going to take a lot of time to do in the OR and are safe and give you better IOP reduction and medication reduction. Quality, communication and expectation management with patients. All of the unhappy patients I’ve seen referred from outside who underwent MIGS are patients that were not consented appropriately. First of all, no glaucoma surgery lasts forever. It’s really rare. Yes, a great Trab can last 20 years but it’s rare. The reality is most fail in someone’s lifetime and we need to emphasize this. It’s better to promise less and achieve more than the opposite. And in a teaching institution, it can be difficult to teach residents in early stages. It takes practice to get great at doing angle procedures it can be done. But you have to be careful. Again, MIGS does have the potential to reduce IOP and medication burden. Don’t give up on it. For some patients, MIGS can serve as a steppingstone also that can delay surgery for more invasive surgery. And sometimes I present it this way. Maybe someone has a visually significant cataract and IOP is iffy. I say this may buy you a few years. We need to do more MIG studies and studies that follow those WGA guidelines. That is one of the things that the field desperately needs. CMIGS I said, please consider it. Especially when you’re combining a aqueous humor outflow increase with reduction. It’s a combination of two different mechanisms of increasing the outflow. There are people doing canaloplasty, I think cMIGS is wonderful. We need more studies and we’re working on it. I want to thank all of you for your attention. I’m story I took the full hour but I’m going to stay around for questions. These are our E mails. I have to thank my research assistant and my research fellow. I couldn’t do any of these studies wouldn’t them. And also these great slides and presentation that I put together. It takes a village. I want to thank all of my donors that help my research move forward: I couldn’t do it without them. Thank you so much. I think now it’s time for questions. This is tough. I know in a lot of places SLT is easier to combine. I’m a big fan of SLT. I published on it and do it a lot. For a lot of younger patients that don’t have a cataract. SLT is the way to go. And many times I use SLT as a time. It’s buying yourself time. I will do SLT and it can last up to five years and then I do phaco MIGS. I’m a big fan of doing SLT in naive patients. Meaning patients who didn’t have any medications. I’ve been using SLT earlier in treatment and it’s working great. The comparison, it’s hard. I think it depends where you are. I typically use SLT in younger patients while the cataract is maturing. I agree about the cost implications of MIGS. We need to work on that. As time progresses we’re going to find ways just like medications. As things get cheaper, I’m hoping that will happen with MIGS, too. Okay. Some videos more — some videos more helped some procedures. I will try to include more next time. Is ECP painful for patients. That’s a great question. I did not touch on this. I work with residents and fellows routinely and I find that blocking, doing an eye block is helpful. My patients are never in pain or discomfort. ECP can be painful if the patient does not get anesthesia. I would recommend blocking the patient, especially if you’re doing Kahook and ECP combined. I have done a few. You have to do a lot of preservative free lidocaine. I coached a patient through a procedure and maybe give you some sedation. What is your take on phaco and FSDS? I’m not sure. Let me see if I can Google HFDS quick. And see if I can tell you. High frequency deep sclerotomy. In the U.S., we are not fans of sclerotomy. This is more of a European procedure. We’re more of a Trab country. I was at a conference in Switzerland last year and I’m going again in June. They talked a lot about it and they get great results but we just don’t do that routinely in the U.S. Thanks for the great talk, what are your talks on pressor flow micro shunt? I’m excited to try it. It’s still not available in the United States to my knowledge. I don’t think it’s FDA approved but I’m excited to try it. It’s going to be another great addition to our armamentarium. I see the pressor flow as taking a place of some XEN Gel procedures: But I think it’s great and I’m excited to try but I haven’t used it. The next question, good afternoon from Nigeria, deep sclerotomy advantage. Deep sclerotomy is not something we do here in the United States routinely. I just can’t say too much about it. I apologize. Same thing with the disadvantage. So I’m going to jump to ALT is better or MIGS, why? I don’t do ALT anymore. I didn’t even train to do ALT. I’m young enough, I’m 40, but I’m young enough that I trained on the SLT arena. If the question is, is SLT better than MIGS, I think it depends on the patient. As I said with another question, I think for patients who don’t have a mature cataract, SLT is my way to buy them time until the cataract matures. To my knowledge there is no comparative studies looking at SLT versus MIGS. One study I’m trying to conduct now is to see if SLT response predicts TM response or TM based MIGS response. If you do SLT and get a great response, will that patient do well with an iStent or a Kahook. SLT versus MIGS is tough. It might be an interesting study but hard to do. May I ask, will MIGS have a role in congenital glaucoma cases. It might. I don’t see congenital glaucoma patients. My patients are 7 years and older. That is my cut off. When I did my fellowship I did some congenital glaucoma patients. But they go to the pediatric glaucoma specialist here. I think in the future it might have a role but I can’t comment too much on it. Many patients come with cataract and glaucoma for the first time. How to go about it? >> I will say my preference is to always do a combined procedure of some sort. I have 29 different consent forms when I consider all of the iterations of the surgeries I do. And I think the main thing now is trying to do more research and maybe even trying to use AI and all the data we have to try to see which one of those 29 surgeries is best for this patient depending on how their cataract and glaucoma are. But I think you just have to do a combined surgery, which one depends on the patient and the stage of the glaucoma and how many medications they’re on and go from there. UCP versus ECP. Let me see. UCP glaucoma, I don’t know what that is. Ultrasound, yes, I don’t have a lot of understand with ultrasound cycloplasty. We talked in one of the review articles, but I haven’t personally used it. I have to say ECP maybe because I’m biased and that is all I have. You can look at the data. It’s not a big part because we don’t use it much in the U.S. but you can look at the data in the review article. Versus micro pulse. I presented a paper comparing phaco 360 versus micro pulse. And they are at least equivalent according to the data. And the paper was published. It was just in presentation. By some areas phaco micro pulse was a little better than phaco ECP but they’re at least equivalent. I could totally see in other countries where getting an ECP machine which is expensive and making sure you have the probe and all that, micro pulse may be replacing it because it’s easier to do. You don’t need to inject Healon inside the eye. It’s easier to do in general. So I can see the micro pulse replacing the ECP. We slowed it’s as good as ECP. How do you choose your patient for Kahook, you can open the synechial angles but really not sure the angles are functioning well. Patients not on blood thinners because Kahook can give you a big hyphema, patients that are not on blood thinners and don’t want an implant. I offer them Kahook. If they have synechiae, I break them in the OR. And I have found, I’m a fan of doing phaco MIGS after a trab and they argue similar things, the TM is not working but I think it works a little bit. When you have synechiae, once you break that and open the angle of the Kahook, I have found great responses. I think the TM is working behind the synechiae and you can break them and do it. Consent the patient appropriately. If it doesn’t work you will have to do something else. The next question, in severe advanced glaucoma is MIGS safe? I think it depends on the patient. I would not do MIGS in someone who has a tiny center island and has shown progression and needs a pressure of 9 and is on a ton of medications. However, it depends. Like that, one of the patients I presented today, the 87-year-old man with cataracts. His pressures were 19 but not 20 or 30. And who didn’t want to have Trab and I did micro pulse. And that’s a strong procedure, to. I think it depends on the patient. You have to be careful. Again, if your pressure is 30 and 6 drops and you have an island of vision, you should not do MIGS. Maybe just a XEN because I think that one is almost as good as a trab in the right patient and depending how you do it. I do think it’s safe for the right patient. That is my short answer to that. How do you imagine hyphema after MIGS. It’s a lot about coaching the patient through it. I find that the most, the hardest thing about controlling hyphema postop is patient expectation. Especially if you’re combining it with phaco. You have a patient who is coming to you for cataract surgery, they’re expecting to see really well after the surgery and all of a sudden they see worse initially if they have a big hyphema. But hyphemas from my experience all go away. I have done thousands of MIGS procedures at this point, I have never seen even severe hyphemas cause an issue. I really think the hardest thing with the hyphema management is patient expectation and coaching the patient through it. If you explain that the vision will get better. That’s my other experience with hyphema and MIGS, usually the pressure is low with hyphema and MIGS. Especially with a Kahook blade. It’s rare that you have a big hyphema after a Kahook. Usually the pressure is great. It’s 9 or 10. It’s more about you’re going to use prednisolone six times a day. I will see you in a couple weeks. It will get better. Coaching the patient. I usually keep patients on six times a day of prednisolone and lots of coaching. Obviously, some of the coaching needs to be done preop. If you coach the patients well, all these hyphemas resolve and people do great. The only thing I will say is the capsulotome rate. I do think when you get a hyphema you will have a higher chance of having a PCO. But you do it and the patient does well. I’m not too concerned about hyphemas in the postop period after MIGS. Are there studies that compare SLT or micro pulse diode laser with any of the other MIGS. I just use SLT in younger patients without significant cataracts before I do phaco with something else with MIGS. I don’t think there is anything comparing SLT to micro pulse but nothing to my knowledge. Would you advice BANG or SutureGATT in developing countries? I have colleagues in Peru that have done BANG and got good results. I think it’s worth a try. It would be interesting to do a study comparing that to the Kahook dual blade in the U.S. and see if there is a difference. I don’t see why not. I think if that’s all you have it’s worth a shot. How many MIGS implants equivalent to tube/trab effect in lowering IOP. Tubes and trabs obviously are still considered the gold standard of glaucoma surgery especially for severe glaucoma surgery that requires low IOP and especially if you’re on a lot of medications and you’re trying to decrease the medications. I think it’s hard to say that any MIGS are ever going to be equivalent, especially to a good trab. A good trab is still the gold standard. So it’s hard to know. But again, I presented some data today showing the phaco trab was as good as phaco ECP. Sometimes it can do wonders. I’m comparing a study now. It’s not that they’re not equivalent, I think it’s patient selection. Because if you have a patient with a central island and needs a pressure of 9 and do a MIGS and don’t inform them that there’s a good chance they’re going to need a trab after, you may have a very unhappy patient. Have you ever had important hypotension. That’s a great question. I have a few times. It’s rare. It’s usually when I do OMNI which I didn’t talk about today. It’s goniotomy 360 or a Kahook dual blade. If you do a cleft you can get hypotension from that. The few times that happened, I can coach the patient through: I usually use atropin and it goes away. I do a laser similar to argon but in the area where the cleft is after I do a — to identify the cleft. It resolves. Thankfully all of these have resolved and many times they resolve on their own. I haven’t had any bad sequella from it but it’s annoying when it happens. Yes, it happened. It’s rare. I think it usually can be fixed if it doesn’t go away on its own. How often do we need to do a repeat Goniotomy in patients with POAG. Is Kahook dual blade repeatable? I think if you did a great job on Kahook dual blade, especially if you do it inside out, I almost do five clock hours many times, there is no utility to repeat it after that. You already opened the — I mean if you saw scar tissue, like in that area, you can go back and open it. But I don’t know, I’m not, I don’t repeat Kahook dual blades. If you fail that, we need to move to something else. Make an ECP or a trab or a tube. It would be interesting to see if you put in an iStent infinite after that. Thank you so much everyone, it’s been a pleasure. I hope everyone learned a lot. I learned a lot from your comments as well. Thank you so much. Have a great day. Bye.

Last Updated: May 15, 2023

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