Lecture: Using Simulation Models to Prepare Surgeons for Their First MIGS Cases

While MIGS surgery is well within the scope of the cataract surgeon, preparation is necessary before performing these procedures to gain a thorough understanding of the anatomy, devices and techniques, and the ergonomics and challenges associated with performing various MIGS procedures. Angle anatomy must first be well understood especially in terms of the landmarks such as the TM and Scleral Spur and various resources are available to help gain this knowledge. The surgeon must become familiar with the particular MIGS technique or device they will be using. Training materials and company representatives (when available) can provide specific information and helpful tips for success. Visualization of the angle anatomy is one of the biggest challenges as the ergonomics involved are quite different from typical cataract and anterior segment surgery. The use of model eyes to practice head tilt positioning, visualization of the angle using a prism, and working with the MIGS devices to simulate the entire surgical procedure is extremely helpful for surgeons prior to actual surgery. These models provide a training platform to practice in a non-stressful setting where the surgeon can make adjustments and gain confidence prior to their initial cases.

Lecturer: Dr. Stuart Stoll, MD, Founder & President, insEYEt, LLC, California, USA


DR STOLL: Good morning, everyone. Thanks for joining. I understand we have a number of people from around the world, so that’s very exciting. This talk with Cybersight is gonna be on models for MIGS. There have been a number of discussions on Cybersight, which I would encourage you to check out, about MIGS. We’re gonna do a lot more than just models here, because we need to get some background. Let’s jump into this. My financial disclosure: I’m the founder and president of Insight LLC. We make the SimulEYE ophthalmic training models. We’ll be showcasing those here. I’m a general ophthalmologist, I practice out of Beverly Hills, California, my focus is on cataract and refractive surgery. I’m not a glaucoma surgeon. I don’t consider myself a glaucoma surgeon, but as we’ll see, MIGS is changing that. The reason I got into this whole thing with SimulEYE and the models is I did a one-year LASIK seminar after my residency, and I found it a challenge to get back into cataract surgery, after having only residency skills and being off for a year. So I had to find ways to develop techniques like capsulorrhexis and other things, and by sharing those techniques that we developed, fast-forward now many years. We have now developed the SimulEYE line of ophthalmic surgical training models, to help other surgeons really flatten that learning curve. And it’s been valuable. We’ve seen it improve resident training, and for surgeons who are out there practicing, when they want to try new techniques, it’s not always that easy to jump into something new and different, and this makes it easier. So just a little quick polling question here. Trying to find out more about our audience. I currently perform some types of MIGS surgery either weekly, monthly, rarely, or never. So if you could just answer that, and we’ll get an idea of the audience here. Okay, so we’re at 27% rarely and 73% never. So really we don’t have a lot of MIGS surgeons here. So this is the perfect audience for this type of session. That’s great. General ophthalmology and glaucoma surgery. Generally we don’t think of those two things as going hand in hand. General surgeons don’t want to deal with the follow-up and all of that. In the words of Austin Powers, that sort of thing just ain’t my bag. That’s sort of changing now, though. In fact, glaucoma surgery with MIGS is now in the domain of the general ophthalmologist, and you are the focus of these MIGS companies. You are who they want to target, because MIGS in combination with cataract surgery is an excellent way to treat glaucoma. So what is MIGS? I think we all have a pretty good understanding of it. It’s an acronym. It stands for minimally invasive glaucoma surgery, in distinction to the traditional glaucoma surgery, the trabs and shunts and tubes. They are more complex surgeries and require follow-up care and bleb management. General ophthalmologists generally stay away from those, because of the time commitment and especially that bleb management. So MIGS is glaucoma surgery. The goal is to reduce intraocular pressure, to reduce or prevent damage to the optic nerve, and we want to try to avoid the complications and the unpredictable nature of conventional glaucoma surgery. And of course, I’m referring to the conjunctiva and bleb management. We want to preserve or avoid the conjunctiva as much as possible. MIGS gives us the advantage of a lot lower risk and lower maintenance, but also generally with lower efficacy. It’s not for every patient. It’s typically for the mild to moderate glaucoma patient. The main thing is we get to avoid that scary bleb. That one looks pretty scary. So let’s talk about MIGS devices and the procedures. There are many ways to classify them. You can look at the anatomy in the eye, where you’re targeting, you can look at the approach, whether you’re coming from an ab interno or ab externo approach. You can look at whether it’s implant or no implant. You can look at the incisional or ablative groups versus the implant. Under the incisional, we have goniotomy, which was really the first MIGS procedure, we’ve got GATT, iTrack, passing the catheter 360 degrees around the Schlemm’s canal, seeing that blinking light. We have OMNI. They also kind of pass a little device through the canal. And both of those devices — you have the ability to inject viscoelastic on the way back, to kind of blow open the canal, and open up the collector channels and help that distal outflow. We have trabectome, which is removing the trabecular meshwork, and also the Kahook dual blade, excising the meshwork, we have ECP, so all of those I see in that same category. Whereas on the other side, we have the implant-based procedures. iStent, iStent inject, iStent supra, in the suprachoroidal space, CyPass, which of course has been recalled, the Hydrus, the InnFocus microshunt, and there are other things coming. The MINIject, the iDose, and it’s an ever evolving, ever changing landscape. As we get better options, it’s always changing. So most MIGS devices and procedures are designed to restore function to the conventional outflow system. That means going through Schlemm’s canal. Some do target the unconventional outflow system, and you have to be familiar with the anatomy. Another polling question. My understanding of angle anatomy is: Excellent, just okay, and what is the angle? So we’ll wait a minute here for the answers to come up. Okay, so we have 50% excellent and 50% just okay. I’m glad nobody said what’s the angle. The people who are just okay, you’ve got some work to do before jumping into MIGS. So we’ll help you on that right now. The key steps for preparing for MIGS — first we have to help you understand the anatomy. And we’ll get to the other points on this slide as we go along. Here’s the angle anatomy. You can see the cornea here transitioning into sclera. Here’s the iris plane coming in, here’s our trabecular meshwork. Here’s our scleral spur. It’s so important to understand how the sclera wraps around, forms the scleral spur, the support structure and housing of Schlemm’s canal here, and that goes into the collector channel. Here’s Schwalbe’s line, the termination of Descemet’s membrane. It’s hard to see, but it’s there. Here’s our trabecular meshwork. I always have to find that. It’s the mesh-like structure at the iris-scleral junction of the anterior chamber. It filters the aqueous fluid into Schlemm’s canal for the conventional outflow. Here’s the scleral spur, the prominent white line. That’s the main anatomic landmark. You find your spur and above that is the meshwork. There’s gonna be other pigmentation up here sometimes, which is false. That’s not the meshwork way up there. You find your spur, find the iris plane, follow it out to the scleral spur, find your meshwork, and now you know where you are. Here’s Schlemm’s canal, which we can’t see with the gonioscopic view. It’s behind the meshwork. It collects the fluid from the anterior chamber and delivers it to the channels for the outflow. It’s basically a lymphatic vessel that takes that aqueous and filters it out. There are 25 to 30 channels that accept the aqueous fluid from Schlemm’s canal and pass it on to the aqueous veins. Here’s a scanning electron micrograph of the angle. Here’s the cornea, here’s the trabecular meshwork, Schlemm’s canal is here, here’s the ciliary muscle attachment, ciliary muscle here, this is suprachoroidal space, obviously this is cadaveric, so it’s different. But devices can slide down here, and sclera is here. It’s very important to understand what’s happening and where the anatomy is. Let’s take a look at a bunch of these pictures. And what you’re gonna see is: They’re all different. The anatomy looks different, the pigmentation looks different, how well the angle is open. You need to start looking at these angles in the clinic. You don’t always have to do this in the operating room, but get yourself trained on the anatomy, and it’s gonna look different in the clinic, versus in the OR. In the OR, your patient is pseudophakic. The angle is much more open. You blow it open with viscoelastic. And you’ll see a lot more of the ciliary body. So here’s the iris. Don’t come from top down. Come from bottom down. Find the iris, the ciliary body band, identify the scleral spur, then you can identify the trabecular meshwork, and there’s Schwalbe’s line, pretty faint. Again, another view of that in a different model. I think sometimes we get too focused in on the little details of which is the scleral spur, which white line is it. But if you pull back, you pull your vision back, and just look and see as a bigger picture, it becomes more obvious. Look here, bam, right there. Scleral spur, that white line. Same thing here. Down there. Scleral spur. Not up here. Down there. Iris plane, scleral spur, TM. Same thing here. Very easy. Scleral spur. Right here. Not up here. This is extra pigment up there. Here’s our meshwork. We find it, follow the iris plane, scleral spur, TM. This is just another view. So orienting it to the anatomy of the eye, the curvatures, iris plane, scleral spur, meshwork, Schwalbe’s line. Iris plane, scleral spur, meshwork, Schwalbe’s line. Again, iris, scleral spur. I don’t want to belabor this too much, but you can’t overstudy, you can’t overlook these enough to be comfortable getting into surgery. The last thing you want to do is come into surgery and not know where you are and where to put your device, where you’re gonna ablate. I think we’ve beat this to death here. So again, iris, much more open. Viscoelastic. You’re gonna see the concavity of the iris here. Very good view. Look how concave that iris is. Look how deep it is. Here’s some ciliary body band, scleral spur, meshwork. So angle anatomy. Intraoperative tips. You can look for blood in Schlemm’s canal. It’s like a beacon in the night. We’re gonna show a video of that. I never enter my eye with the MIGS device until I can see the target. Patient in prism, gonio prism on, identify the target, know where you’re gonna go, get a good view, and then you go. Through the gonio prism, the TM can appear a little more flat, even though it’s actually curved, so be ready for that. Angle anatomy. We didn’t just learn everything there is to learn in this lecture or other lectures on Cybersight. Cybersight is an excellent resource. I would encourage you to go to many of these MIGS lectures. The companies are out there to support you. There are multiple lectures, meetings, you can see surgical implantation videos by experts on YouTube and EyeTube, all the latest devices being tested in trial, you can see the experts putting them in, and they’ll show you tips and tricks. Two excellent, excellent websites you all have to go to: Gonioscopy.org and anglesurgery.org. There’s no substitute for those websites. You want to put gonio lenses on your patients in clinic to see the angle structures. There is going to be significant variation in anatomy and pigmentation. And here’s a huge tip: Practice intraoperative gonioscopy on routine cataract patients. You don’t have to have a model to practice all this. You have patients right there. You’re not gonna do any harm at the end of your case. Put them into head tilt, adjust the microscope, we’re gonna show you all that. Get the view, put the prism on, go out there, with a hook, with a viscoelastic cannula, go out there and identify the landmarks. Okay, so polling question. My understanding of angle anatomy is — it’s the same question. Let’s just see if we have any difference from what we did a minute ago. Excellent, just okay. Nobody said what’s the angle before, so I think we’re good there. We’ll just wait for that result to come up. Okay. We went from 50% to 80%. So that’s good. I’m happy this is useful. There’s a lot of work to do, though, outside of these lectures. Back to key steps to prepare for MIGS. You have to understand how to achieve optimal visualization of the angle. This is so important, to get the view and maintain the view. So let’s go through that. Visualizing the angle requires a gonio prism. You’ve used a gonio lens in the clinic, a tear film lens or gonio gel lens, but not a gonio prism. Get one and start putting it on your patients. You need to have additional viscoelastic ready. You have to fill the eye, pressurize the eye. I like to use a thicker visco, like a Healon GV. We’ll talk about that later. You need viscoelastic on top of the eye to couple the prism. Patient position is so important. Your scope has to be able to turn. Your patient has to be able to turn. They have to have the flexibility in their head and neck and they have to be stable. Don’t have your first patients be somebody who has really bad neck problems or nystagmus or something like that. We need a nice stable platform. The surgeon positioning is also important. You’re gonna be in a different ergonomic position. Your chair height has to change. The oculars have to be tilted back up. Either an assistant has to do that, or you have to have sterile handpieces on those where you can reach down and adjust it yourself. Your chair height is gonna change. You need a chair that can easily raise and lower. Approach angles. Where you sit, you might want to adjust your positioning away from the incision, to get a better position there. You have to have adequate magnification with your scope. It’s helpful to increase illumination, so you can focus in on the structures. And the key is to maintain the view throughout the procedure. And we’ll talk about that as well. So again, these visualization skills are key to success. It’s imperative, absolutely imperative, to practice this intraoperative gonioscopy on standard cataract patients in advance. Let’s take a look here. This is a nice video done by Jason Jones, showing intraoperative gonioscopy. He’s got the prism on. Watch him focus in now. You can even zoom in more. There you go. Fill the view. The prism — fill your view. Look at the beacon of blood in Schlemm’s canal. There’s no question of where your anatomy is here. We’ve got scleral spur and anatomy. Sorry, let’s go back to that. There’s a bunch more there. I just timed out of it. Let’s watch a few more of these. Focusing in… Getting zoomed in. That was interesting. Did you see the little bit of blood that came up? You can see it there. You can see the blood under the surface of the cornea. So make sure you’ve got your field cleared of blood. And then get the viscoelastic on there. Here’s another view. Look at where the position of the prism is. It’s not way back on the eye. It’s almost more forward. As you tilt forward, you get a better view. And look at how he’s able to hold and maintain that view. Let’s jump ahead here a little bit. Here’s another one. Fantastic view. The concave iris. It’s opened up by the viscoelastic. No question where that anatomy is. The scleral spur stands out. The blood in Schlemm’s canal stands out. Very easy to identify. He’s maintaining that view very nicely. Things get out of focus a little bit. You can see how putting some pressure and moving around, you can distort your view. So you’ve got to learn to float that prism on there. Again, another view. Look at how easily it stands up. There’s no reason not to have a good view and practice on that. Okay, let’s move on. So here’s with the model. You can just put viscoelastic on the top. Add visco to the cornea, and you can practice with sliding your prism around. The key is a light touch. So with these models, you’re not gonna be able to indent the cornea and get the folds. It’s gonna be easier to maintain your view. But you want to learn that light touch. One of the biggest tips I can tell you — they always say don’t push down. Have a light touch. Float. But I almost like to say: Pull up on that gonio prism. Not so much that you’re gonna uncouple it, but just enough to really open up the cornea and not have any folds. Here they are, demonstrating visualization. This is a model that Glaukos used to use to help demonstrate prism and the view, but they weren’t able to implant the stent in there, so we worked with them to develop something where we actually can implant into a model now. Okay, let’s move on to another couple videos. Here’s other ways you can practice. So this is showing that you want to have the correct angle on the prism. You don’t want to be too far tilted forward or back. If anything, tilt forward a little bit. You can practice — take a mark. Take a word like this. With viscoelastic gel or just in water. And you can see what happens to your view as you tilt too far back. You’re gonna distort your view. Imagine if you’re trying to find the angle structures. It’s not gonna happen. So if you rotate that prism more forward, like that, you’re gonna open up your view. You’re really gonna get a nice clear view of the anatomy. Let’s do a couple more here. This is just showing the design of this particular prism. Notice what’s nice about this — is it’s a very wide angle view, and it has that curvature, that cut-out for your incision. So you can more easily get into your incision. But look how wide it is. There’s all sorts of different gonio prisms out there. Try different ones. Find out what’s best in your hands. Find out what you need to help your patients and help yourself get that view. It’s a tremendously wide view there, and you’re not hitting the device, as you go through the incision. And one last one. So this is another attachment that they have. If you need to stabilize the patient, they have a device now that you can clip onto the prism, so you can actually rotate the eye. Or let’s say the patient’s having trouble looking in a certain direction, or they’re blocked, and they can’t move their eye where you want them to. You can actually use this clip and rotate and stabilize the eye while you’re doing the implant, or whatever procedure it is that you’re doing. Okay, so pearls for optimal visualization. Better visualization has a greater chance of a successful MIGS procedure. That’s just the bottom line. If you don’t have a good view, nothing is gonna happen properly there. The surgeon and the assistants need to know how to turn the scope and the patient’s head to get the best view. Don’t let your first MIGS case be the first time you do this. Practice on your routine cataract patients. We can’t emphasize that enough. You have to release the tape on the patient’s head, if the patient is taped down. I like to cut both sides of the tape, but you just have to cut the side towards you. Consider a pillow under the patient’s shoulder to help support them, if that’s helpful. You definitely want to increase your mag. I like to focus — before I get the prism on there, I try to get a rough focus on the distal limbus, and that way I know that I’m pretty close to being in focus on the TM, so that when I get the prism on, I don’t have to do a lot of focus at that point. Ensure the microscope can deliver adequate illumination. You can use a miotic agent to bring the pupil down. I don’t think it’s really necessary, but it’s certainly not harmful in your first cases. You definitely want to use a nice cohesive viscoelastic. I like Healon GV for this. It’s just really solid. It gives you a nice fill of the anterior chamber. It opens up the angle and it really pressurizes the eye. So if you do have a little bit heavier feel or touch on the cornea, you’re not gonna get those corneal folds as easily. The things that are gonna drop your view — if you’re distorting your incision and losing viscoelastic, and if you’re pressing on the cornea, you’re gonna get those folds, and that’s gonna kill your view. Both of those things have to be happening. You have to float on the incision, you have to float on top of that cornea, and again, I like that technique of: Actively thinking of pulling up slightly, with the prism, to not be pushing down. You want to add a heavy dollop of visco on the cornea, and then have this light touch, like we’ve been talking about. If you distort the wound or the cornea, you’re gonna lose your view. And again, don’t proceed with any MIGS procedure, until visualization is achieved. So preparing for successful intraoperative gonioscopy — you’ve heard me say it a few times. I’ll say it again. Practice intraoperative gonioscopy on patients that are having standard cataract surgery. Practice turning the patient’s head and tilting the scope, getting light pressure. Practice getting comfortable with different body position. When you turn that patient’s head and turn the scope back towards you, all of a sudden you’ve moved back a way, so your arms are gonna be much more extended, your elbows are gonna be in a different position, your hands are gonna be resting differently. Practice getting comfortable. Practice visualizing the anatomical landmarks, and practice with another instrument, like a Sinskey hook. Or take the viscoelastic cannula. Go out there, see your anatomy, touch the meshwork. Touch the spur. You can do all of that safely. So here we can talk about patient and scope positioning. The patient head — you don’t want to try to get all the change in either the patient head or the scope. Do half and half. So rotate the patient head 35 degrees, and tilt the scope about 35 degrees. Let’s take a look at this little video here of that happening. So here we are. The patient — they just finished the cataract portion. An assistant is tilting the scope. I like to have a sterile handle on there, where I can do that myself. Because I know exactly where I want to put it. I don’t have to rely on somebody. As the scope tilts down, look at where the oculars are going. The oculars have to be tilted back up. Let’s bring those oculars back up into line, and once you do that, you’re still tilted a lot further down, so you have to adjust your chair height position. You have to have a chair that you can drop easily. Now we adjust the patient’s head. The tape’s been broken. We’re gonna rotate the patient’s head over there to about 35 degrees. Again, you’re gonna adjust your chair height and the bed height, adjust the oculars. It’s so much easier if you have sterility there, that you can do it yourself. And adjust the patient position to optimize your approach angle. This is just showing — just like with our phaco incisions, you don’t necessarily want to be directly in line with your phaco incision. Same with MIGS. When you’re using a device, give yourself that positional advantage. Be off to the side 15 degrees so you’re not jamming your wrist. You want to be very comfortable and relaxed and no tension or stress when you’re doing these devices. It takes a very steady, good positioning. Okay. Let’s move on now to these next three points. Understand the device and injector, including features and benefits. Understand the implantation technique and know the surgical and procedural checks and contingency plans. If you’re working with a MIGS device, I don’t care what device or what technique it is — all of this information can be obtained through the company. They’re there. They want to support you. If you can’t — if you don’t have local representation, you can get it online, through websites, through EyeTube and YouTube, through lectures, but all of this stuff, all of these next three points, come from the manufacturers. They’re gonna have their knowledge base out there, for you to tap into, and be able to teach you this stuff. So, for example, with Glaukos, their newest device, the iStent Inject, it’s a very high-tech device. It’s tiny. You can’t really visualize it all that well. You need to know what’s going on, understand the size and where it’s going. You’ve got your conical head here, the side flow outlets. There are four of them. The neck. Flange back here and the central inlet. Basically we’re embedding this thorax in the trabecular meshwork. It’s made of titanium, coated with heparin, biocompatible. You need to understand this if you’re working with this device. You have to be comfortable with the injector. Just like you’re evaluating a new IOL. It’s not enough to evaluate the lens. You have to evaluate the injector and know how that works with the patient safely to get those in the eye. Same thing here. Oftentimes there may be a device or implant, and there’s gonna be an injector. So evaluate. Know the components. Know where the buttons are that you have to retract or push. Know that you have a microinsertion sleeve, and then you have a microinsertion tube. Here the stent is lined up, the trocar, the V slot. Understand that you have to keep the trocar very well centered in order to deliver the stents into the proper position. If this is bent off to the side, these are gonna hang off and hit the insertion tube. The company will teach you all of this. They’re gonna have their surgical scenario matrix. When you implant the first implant, you dimple, and the second one — what happens if you don’t get the first one? If it underimplants? If you flush, you do a double stack — they’ll have a flow sheet to teach you. We’re not gonna go into that right now. But the point is: Rely on the company. They’ve been through this. They know how to teach this really well. Let’s talk about another MIGS technique with Ellex, the iTrack Surgical System. This is ab interno canaloplasty. Very high-tech. You’ve got this viscoelastic you’re gonna inject on the way out, and this is the key. This catheter. The technology here is incredible. They’re gonna show you what’s in their technology. So this tiny little catheter, you wouldn’t believe how small this catheter is. It’s got a polymer staff and distal atraumatic tip, like a bulbar tip, that helps you pass this catheter into Schlemm’s canal and around the canal, 360 degrees. You’ve got an optical fiber for light transmission. You get the blinking light to see it safely. You know you’re safely passing around the canal. In this tiny catheter, you have a catheter support wire to give it some stability, and you have a lumen. This is incredible. When you see how small this catheter is, to have all this technology in this tiny little catheter — you catheterize the cannula 360 degrees and on the way out, you’re injecting viscoelastic, maintaining the anatomy, blowing open the canal and the collector channels, and you’re improving the outflow through the conventional system. These companies, they work with the key opinion leaders, the leaders in the field. They do research. They have anatomy. They can teach you. You’re gonna see material and information like here’s our Schlemm’s channel and here’s the episcleral veins. Stuff like this, that you may never really understand or see otherwise. They’re gonna show you not only anatomy but pathophysiology. What’s happening in glaucoma. Things like tissue herniation in the collector channels. They’re gonna explain to you why their technology works. Why they believe that their technology can help your patients. How you’re gonna catheterize the canals, you’re gonna break through these herniations, and open up the channels. Okay, so let’s get into some of the fun stuff. And the last thing in our key steps to prepare for MIGS is practice, practice, practice. That is certainly a mantra, including with models. We know we can practice on patients. We know how now. But we also can practice on models when they’re available. Let’s do another quick polling question here. Before my first MIGS surgery, number one, I practiced with models, I practiced on animal eyes, I practiced with human eyes, or I did not practice on anything prior to my first cases. I guess we’re assuming that you guys have done some MIGS cases. Let’s see if you guys have practiced. I’ll just wait a second for the results to come up. So 36% practiced with models. That is fantastic. 45% practiced on animal eyes. 0% practiced on human cadaver eyes, and 18% did not practice on anything. Not practicing on anything I think is — that’s not where we want to be. We want to practice at least on our own cataract patients, to get the positioning and get that, and then you can practice on a device, even if it’s just holding it in the microscope, outside, getting a sample of it, and practicing. Human cadaver eyes — when I was trained on MIGS, initially, by Glaukos, for the initial iStent, they had corneal rim tissue. So it was human cadaveric tissue. There were advantages, you could implant into the tissue, but it wasn’t a realistic experience of getting and maintaining the view and all that goes along with the patient tilt and all that was new in MIGS and the positioning for me. It’s fantastic that people have had access to models. Animal eyes obviously have their limitations. We’re gonna talk about some of that. Let’s see if we can move forward here. Okay, so in terms of practice, we’ve been over this and over this. You can practice on patients having standard cataract surgery. You’re not gonna practice with the actual device, but you can practice the other 80%, which is getting the view and maintaining the view. With human or animal eyes, there’s obviously limitations there. There’s cost, there’s availability, there’s sterility, safety issues — you can’t take these into your own OR, and quite frankly, they’re really not that pleasant. And pig eyes, they don’t even have a canal of Schlemm. There was a nice study that showed that the canal of Schlemm in certain pigs is absent. Model eyes — I’m not saying they replace everything, but they have a very good role that can be used inside or outside of the OR, and they allow you to practice the entire procedure. They really are a nice adjunct to this. So with models for MIGS, the use of model eyes, you can use them to practice hand tilt and head positioning. Working with the MIGS device to simulate the entire surgical procedure — we found that to be extremely helpful for surgeons, prior to the actual surgery. This has been validated by feedback from many experienced and novice surgeons, as well as the companies that we work with, utilizing the models. These models provide a training platform to practice in a non-stressful setting, where the surgeon can make adjustments and gain confidence prior to their initial cases. We’re not trying to be exactly tissue. Tissue has its limitations. It’s hard to obtain and all of that. But these models — they’re not gonna be the perfect tissue representation, but they’re gonna provide a great training platform to learn all the steps, and there are no penalties for mistakes. You can practice and practice and practice and get comfortable. There are various eye models to practice different MIGS procedures. Again, there are limitations. It’s not actual tissue. We’re not gonna necessarily create the corneal folds. It is gonna be easier to maintain the view. But I think that’s valuable. We want it to be a little bit easier in the practice setting to get confidence going into the surgery. But you can’t just jump in without the background and understanding. Not only do you need access to the MIGS devices, but also the models, and you can turn to industry for this. These companies, they want to promote their devices. They want to educate you. They want to support you. And they will get samples to you. They will train you. They have the models. You don’t need to come to us and purchase models from us. Go to the companies. Mostly available through device companies, through dry labs, at the various meetings. There are dry and wet labs set up, to practice and train and learn these techniques. All MIGS techniques can be performed on models. Again, may not be exact tissue feel and performance, but it acts as a platform. You can get a feel for the device and the inserter inside an eye, within the confines of an incision and under gonioscopic visualization. You can see what it’s like to be in that incision, trying to get the view, both hands together, adjusting your foot and the microscope. Getting the ergonomics down. This is particularly important for your first MIGS procedures, and you can do it over and over again and get muscle memory. So again, contact your local reps. Reach out to the companies. And have your rep there with you during initial cases. Even for later cases, for more advanced tips, when you get to a certain level, they’ll come in and teach you more of the subtleties of hand positioning and what to do when. So you can retry things again on the models. But lean on that rep for support whenever you can. One of the keys with models for MIGS and just MIGS in general is: You’ve got to have a tilting stand, and you’ve got to have a tilting scope. In your OR, your scope has to tilt, and you’ve got to have a stand to set up the model that tilts. Here’s an example of our MIGS kit. It’s very compact, and it takes just a minute to set up and take down. You can get a nice angle here, 30 to 35 degrees, the base unit sits here, and the eyes will attach on to that. It goes down compactly to fold away very nicely in travel. So when we worked with Glaukos, they already had this stand available, because they were using it for visualization with their other model. When we started working with them, they wanted to continue using this stand that they liked. It allows hand positioning as well. Ours does too. But they were committed to their device, so we created an adapter that our eye can go onto, onto this Glaukos stand. So we’re gonna get into the models here, and showing some videos, but if you want to be like Ike, you’ve got to use models. And let’s see what Ike has to say about models and MIGS.

DR STOLL: That’s exactly right. Ike is fantastic about reducing pressure for his patients, and models can help reduce the pressure for you, as you go into your first MIGS cases. So let’s take a look here. Alcon CyPass. We know the device has been recalled. But look at this video. You can see how it’s helpful. We’re gonna put the viscoelastic on top, couple the prism, get our view, you can see the TM and the scleral spur. In this case, we’re going suprachoroidal, we’re gonna disinsert the ciliary body there, slide into the suprachoroidal space, release the device, and tap it into position, all under gonioscopic view through the incision. Let’s look at another one now. Here’s our friends with New World Medical. They have the Kahook Dual Blade from Dr. Kahook. You saw his lecture last week here, I believe. Again, viscoelastic on. This is a different model. This meshwork we can actually excise. So you can practice different techniques of initiating — incising the meshwork, and then removing it. Whichever technique or pattern you’re comfortable with, wherever you want to start and finish. You can remove the tissue. You can get a feel for the blade sliding in there, being oar locked in the incision and rotating in the canal. Our friends with the Ellex iTrack device — you can see the catheter here, the blinking light as it goes through the canal. Look at this nice elegant setup. This is not a big OR setup. This can be done a lot of places. They’ve got this great microscope with tilting capabilities. Here’s the illumination box. Here’s the stand with the eye on it. They’ve got a camera on here and a screen, so the trainer can help support and see what’s going on, and minimal equipment setup required. You’ve got the eye under here and you can see what’s happening there. You can take this same type of stuff and put it in the showroom. So you’re gonna go to the meetings. You’re gonna see this, little dry lab setups at the show. Here’s a surgeon with the setup, and this is in the SimulEYE. He’s got the prism, the forceps that they recommend, here’s the blinking light. He’s just starting to put it into the Schlemm’s canal through the goniotomy. This is a great video. This comes to us courtesy of Dr. David Lubeck, the Ellex chief medical officer. It’s a little long, but it’s well worth watching. Let’s take a look at this video. This is comparing the difference between the model and the actual human surgery. So here we are, going through the incision. Filling the model. We have preplaced side port incisions, because the catheter is so delicate, to try not to bend it. So we preplace those in the eye. Taping the catheter down, just like you would do next to the patient’s head, getting everything in position, and here we are in the actual eye. Filling the eye with viscoelastic to deepen the angle, and similarly taping it right next to there. And the positioning of that is important, because we want the correct angle. Here he’s making the paracentesis at the correct angle. He’s going to insert the catheter, and you want to lay it right up there, where your goniotomy is gonna be. Now putting the viscoelastic on the eye, so we can couple up with the prism. Get a nice view. In this eye, we have a premade goniotomy, which is easily recognizable there. Because we want to be able to use those eyes over and over again, we didn’t want that consumable element in there. And also for speed of use in training, we want people to get into the heart of this, which is passing the catheter. So getting our view, here he’s gonna make a goniotomy. This is a fantastic view. Watch him take down the anterior part of the trabecular meshwork. And open it up, and you can actually see the back wall of Schlemm’s canal there. Fantastic. So we’ve got a goniotomy there. Now we’re gonna pass with the MST forceps and very atraumatically pass it into the canal. You can see the light passing, and as it continues, you can see the light. It can be blinking or solid. You’ll be able to visualize this on the outside there. It’s blinking, coming around the limbus, and then we’ve cut — we’ve fast-forwarded here, and now it’s coming in through the last 360 degrees, and into the angle again there. And now you know you’re 360 degrees. Here it is on the human patient. Passing it into the otomy there. Carefully. Atraumatically passing it around the canal. We’re gonna see the blinking light come around. And we know we’re safely in the canal. That blinking light is our beacon. We know we’re safely in the canal. It’s passing without resistance. It’s passed around there, and here it comes into the eye again. We know we’ve gone 360 degrees. And now pulling it back, and on the way out, this is where viscoelastic is getting injected. So we’ve broken open those herniations on the way forward. On the way back, we’re injecting viscoelastic. You can see the light passing back around the canal. In the model, we don’t necessarily need to inject viscoelastic, but that can be simulated, and here we’re pulling it back out, and we’ll see the same thing in a moment of safely, atraumatically removing the catheter from the eye, to complete the procedure. Which is here. He puts a hook in. He supports it, so there’s no extra pressure on the meshwork. And here we are, pulling it out. You can see the blinking light going around. It’s passing safely and smoothly. Viscoelastic is being injected in, and opening up those collector channels. Fantastic video, showing the back and forth, between the human eye and the SimulEYE. I really appreciate this work by Dr. Lubeck. Okay. Let’s look at another one. Here’s the Glaukos — this is the model we just did for the iStent inject. Going in, filling with viscoelastic, they wanted the clock hours on there, because part of it is you’ve got to be 2 clock hours apart, ideally. So we’ve got our view, we’re tracking the protection sleeve, going over, hitting the button, and implanting the iStent inject. They’re very small. It might be hard to see. But bam, there they go. We’re actually able to implant the device, get a feel for that button, pressing the button. Let’s do that again. Kind of run that again. So again, the clock hour marks. But basically you’re in such a small space under view, and there’s gonna be a feel to that button. So when you press the button, there’s some resistance. You want to have your hand position exactly where it needs to be. You’re gonna dimple a little bit, so that you can implant the stent. Not too much, not too little. Try to get a couple clock hours apart, and deliver that device. Here’s the setup. This is my OR on the left hand side. We set this up just to take this picture. We got the Glaukos stand with our eye on it. Here’s some injectors for the iStent inject. Viscoelastic and a prism. That’s all we need. It’s pretty simple. We’ve got a tilting scope, we’ve got video capability. So the techs can see it, other people can see what’s going on, and you can see the eye up there. You can do this in your own OR. It’s not animal tissue. Here is another setup. This looks like more of a wet lab setup that Glaukos did. You can’t see it too well, probably, but this SimulEYE here has multiple devices implanted in it. You can practice over and over again. Just keep getting the feel of what it’s like to deliver, dimpling the meshwork, implanting. That’s what you need to do. So our model — practice safe MIGS with super models! We’ve got our KDB model to exercise the meshwork, we’ve got the iTrack model for Ellex, to help catheterize and go 360 degrees around the Schlemm’s canal, and we’ve got the iStent inject model to deliver that device into the meshwork and get it in there, in the proper position. You’ve just got to practice. I can’t overemphasize it. There’s so much you can do now to practice, practice, practice, before your first cases. You know, with MIGS, you’ve got to keep calm. You can’t have a shaky hand. You can’t have nerves. You’ve got to practice before you go into your cases, and if you do, if you practice, you can keep calm and you can get that view. You can have a lot of success right from the beginning, and you’re gonna find MIGS to be a lot more enjoyable procedure, and you’re gonna find nice outcomes for your patients. So I want to give a special thanks to our industry partners that we work with. To New World Medical with the Kahook Dual Blade, Ellex, for the iTrack procedure, and Glaukos for the iStent inject. We partnered with these companies to develop the models specifically to their needs, to get the training to you guys that you want. Our whole model is with the SimulEYE models — our model is training surgeons, supporting industry, and improving outcomes. And I believe we’re having an impact in ophthalmology and the ophthalmic community to make things better and safer for our patients. And of course, I want to give special thanks to Orbis and Cybersight for allowing us this time and this opportunity to share with you guys. This is a production run of our models that we did. Just thought it was a nice picture, to kind of show the view of all the models there. So thank you for your time, and for joining us. If you want more information about the models and what we do, please visit our website at SimulEYE.com. Thank you very much.

DR STOLL: Are there any particular model eyes or heads to use? Are there any low cost options available? So particular model eyes — obviously what I know most about is our line, which is the SimulEYE models. There are certainly other models out there. I don’t know exactly which companies or which devices they’re working with, but we work with those three major companies. Heads to use… You know, we have our stand. That works with our eyes. Our eyes work with a suction cup base. So any flat smooth surface can be used, or heads can be modified. We’ve even used our eyes in styrofoam heads. We cut out an area for the orbit and put a little cap in there. There are ways to modify these things, for sure. Are there low cost options available? The lowest cost options are reach out to the companies. If they’re in your area, if you have access to these devices, reach out to the companies. Say I want to get trained. I want to get practice. They’ll come in. They’ll bring the device. You have to have the device or the samples, and they’ll generally bring their training devices, whether it’s our models or something else. They’re gonna bring that in. So that’s about as low cost as you can get. Hi, I just finished my residency. Are those devices cost effective? I think they’re very cost effective. Again, if you reach out to the companies, you go to the meetings, you don’t have to pay anything for this training. The companies want to train you. They want to find you. They want to promote their procedures. They’re effective and they’re gonna work with you. How soon will this type of procedure be available in Africa? That I can’t speak to. You would have to reach out to our friends at Orbis. I don’t know where things are with that. But certainly some procedures lend themselves more to an area like Africa than others. Some devices are less involved from a technical standpoint. For example, I think a Kahook dual blade is gonna be more readily available than something that requires a lot more setup and materials. How do you simulate intraoperative blood reflux? Is it possible? It’s possible. We’ve done it. It’s not really necessary. Yeah. That’s not something that we found that was really important. It adds a lot of setup, a lot of cost to the models. And I don’t think it adds really much value. In developing countries, what is the best approach to learn cataract surgery? To learn cataract surgery? Wow. Well… Gosh… Learn from your mentors. Learn from the people around you. The cataract surgery techniques there are so different from here. With small incision cataract surgery. There are people that are really out there, driving that field, and teaching it, but there’s videos online, of all the techniques. So you’ve got to reach out for those. The indication of MIGS — that’s a bit more than what we can cover right here. There was another really good lecture on Cybersight, so look for that. About the indications of MIGS. All that stuff is covered. Go to Cybersight. It’s such a valuable resource here. That you guys have access to. What are the benefits of the patient? Well, MIGS — it’s microinvasive. It’s low risk. It’s easy to do. There’s not a lot of follow-up that’s required. It’s just low impact for the patient. No bleb, no bleb management. Huge benefits for the patient of MIGS. And which MIGS procedure is the most effective in the long run? Wow, that’s a big question. There’s a lot there. It really depends on the patient. What you’re comfortable with. I guess the best MIGS procedure is the one you’re the most comfortable with. But get comfortable with multiple procedures. If you want to treat your patients the best, figure out what’s best. And that’s still being determined. The key opinion leaders, the experts in the field, they’re helping us understand when should we turn to what procedure? Should we be targeting the meshwork? The outflow? Should we be bypassing the conventional system? Which patients benefit from which procedures? Do we need to go to a more aggressive procedure, like in a more advanced glaucoma patient — maybe we need to still have that bleb, or something like a XEN, that helps us with a more controlled bleb. It depends on so many factors. Where the patient is with their disease and where the surgeon is with their skill level. I hope that provides answers to your questions.

DR STOLL: Okay. So low cost model for Nepal… Again, I don’t know what we’re talking about, when we say low cost. But if you can reach out to the companies, you’re gonna have low cost options for free, as the companies have trainings set up. So I don’t know how the devices are accessed there. But all I know is the models that we’re doing. Thank you. Can you talk about rejection in relation to these devices in humans? That’s a good question. These devices — if we’re talking about the implants, the things that we leave behind in the eyes, I’ve never seen or heard of cases of rejection, per se. Now, there can be things like fibrosis, there can be problems like we saw with the CyPass, where there was some endothelial cell damage, and it’s very likely that that was positioning-related. If surgeons weren’t getting it tapped down. It depends on how you compare those things as well. But to say rejection… These are not graft materials. These are not cadaveric materials. These are synthetic materials, and they’ve been tested and designed. I have not heard personally about rejection, like an immune response, to these devices. And then we have: What is the cost of the models? Cost of the models varies considerably, depending on if there’s a consumable element, to a reusable element. They’re not cheap, but they’re effective. And they can range in price from $40 to a couple hundred dollars. And of course you have the kits to set things up and the stands. And that’s why I say hopefully you don’t have to bear that cost yourself. You can reach out and partner with the industry. They want to find you, so if there’s a given region or a hospital or a center that wants to bring a MIGS device in, contact the company and see what they can do. Because I bet they’re looking for you too. So I think that’s all of our questions that I see.

DR STOLL: Is it reusable? Certain of them are. For the ones where there’s a consumable element, like our model with the Kahook dual blade, we’re excising the meshwork. You can rotate the eye and do three or four treatments, but then it gets consumed. For our model with the Glaukos iStent inject, again, that meshwork is getting consumed. But you can implant a lot of stents in there. The meshwork runs 360 degrees around the eye. So you can rotate the eye, make a new incision, put some more viscoelastic in, and keep implanting, as long as you have those devices. For our iTrack model, that model is pretty robust. It is reusable. You can catheterize it, get the cannula, the catheter around the Schlemm’s canal, pull it out, do it again and again. The catheter is very delicate. You want to have a nice light touch. Just as with in surgery. If you have that light touch and you develop that skill, you can reuse that model multiple times. You might need a couple catheters to get to that point, because you’ll find the catheter is delicate, but that’s important. You have to understand how delicate the catheter is. How you have to handle it and grasp it carefully, because that’s what you’re gonna do when you’re in surgery. How effective are these devices in lowering IOP? Well, they are quite effective. They’ve been studied. Again, going back to the beginning of the talk, where we said MIGS devices — part of MIGS is they’re safer, they’re easier to use, they’re easier to manage, but they’re not as efficacious as traditional glaucoma surgery, like tubes and shunts and trabs. But they are effective, and you’re gonna find out in your hands what’s the most effective for a given patient. I think the rest of that question is a bit beyond the scope of what we can go into right now. Are there any other questions? Okay. So I think that wraps that up.

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March 14, 2019

Last Updated: October 31, 2022

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