During this live surgical demonstration, two cases will be presented with ongoing live dialogue between Drs. Kevin Barber and Hunter Cherwek. A toric IOL case using femtosecond laser, digital marker and ORA intraoperative aberrometry will be performed with discussion on techniques for successful implementation of refractive and toric IOL technologies. The second case will be a phacoemulsification case with MIGS, using the Kahook dual blade for treatment of moderate glaucoma. Live Q&A will be hosted during and after each case.
Surgeon: Dr. Kevin Barber, Central Florida Eye Specialists, Florida, USA
DR PACHECO: Good morning, everyone. Good afternoon. And good evening. And welcome! Happy new year to all our friends and colleagues around the globe. We want to thank you for joining us today. My name is Lori Pacheco. I’m an ophthalmic registered nurse. I work with the volunteer faculty team here at Orbis. And with me is Dr. Maria Montero, the head of ophthalmology for Orbis’s Flying Eye Hospital, and together with Dr. Kevin Barber, we’ll be moderating today’s live surgeries. And we want this to be interactive. We want you to participate with questions. We encourage you to ask questions through the question and answer button on your screen. Just type in your question and at the end we will go through as many as we can, that time allows. Welcome, Dr. Barber!
DR BARBER: Morning, everyone. My name is Kevin Barber. Thank you for the introduction, Lori. I’m a refractive cataract surgeon here in central Florida, and I welcome you all to my operating room. Really happy to share with you today just a little bit of my journey as a refractive cataract surgeon. When I did residency, we did not have toric. We didn’t have MIGS procedures. So those are skills that I had to learn and had to incorporate into my practice. After training. And so I’m hoping to share some pearls with you guys, so that those of you interested in adding these skills to your armamentarium — you can do that. So I have three basic objectives for the next hour. I’m gonna present two cases. The first case will be a femtosecond assisted surgery, where we’re gonna place a toric intraocular lens. We’re also gonna use a digital marker and intraoperative aberrometry for teaching purposes and teach you some of the pearls for placing toric lenses. The second case will be a manual phacoemulsification, and in that case, we’ll be performing a MIGS procedure, using a Hook goniotomy knife as treatment for moderate glaucoma. The third objective is I’m using a 3D visualization system for these cases. The Ingenuity heads up display system. It gives some perks as far as streaming and teaching. I hope you will appreciate that today. With that, I’m gonna go scrub and get started on our first patient, and I’ll introduce Dr. Maria Montero from Mexico. She’ll give you some background information on our first patient this morning.
DR MONTERO: So our first case is going to be a left eye and it’s going to be a femtosecond assisted cataract surgery with a toric intraocular lens using a digital marker and intraoperative aberrometry. Like Dr. Barber just mentioned. It’s a 73-year-old female. With myopic astigmatism, and a cataract that is classified as nuclear 3+. The preoperative refraction is -5, with +3 at 96 for astigmatism, and the best corrected vision on that eye is 20/60. So for those of us who use minus cylinders, it’s -2. With -3 for astigmatism at 6 degrees. The patient desires monovision, with -2.25 outcome in this eye. The pre-op keratometry is -3 diopters of cylinder. Axis 106.
DR BARBER: Perfect. Thank you, Maria. Do you have a good view of the microscope now?
DR PACHECO: There we are. Beautiful. Yes.
DR BARBER: Perfect. All right. Thank you, Lawrence, for spotlighting that. All right. So I’m gonna go ahead and get started. As you guys can see, we have already applied the femtosecond laser application. I do not use the incisions. I prefer still manual made incisions, because I can place them exactly where I want them. This is a 1.2 millimeter paracentesis. Now going to fill the anterior chamber with a viscodispersive. You’ll notice I’ll go all the way across the anterior chamber, and fill from the most distal part, backward. This allows for exchange of aqueous. Which will give you the most consistent pressure. That’s important as you create this. I’m gonna go right at the limbus. I’m gonna engage the stroma. Once I engage the stroma, I’m gonna rock the heel of the blade and go up 2 millimeters. The blade will enter into the anterior chamber, drop back down, and go all the way in. You can see the internal lip or the internal incision here is a straight line. That’s our goal. It’s a Chevron sign for the keratome. That’s not gonna seal as well. So you’re always looking for that internal line to be straight. Now, you’ll notice here that there’s a few tags. Where the capsulorrhexis is not — possibly not complete here and here. So I’m not going to just grab the capsulorrhexis. I’m actually going to walk it around. Just like you normally would in a manual. Case. Make sure I don’t cause any tears. In our anterior capsule. Now, if you haven’t seen a lot of femtosecond cases, you might notice some unusual signs here. You see these large bubbles. Those are air bubbles created by the femtosecond laser. Those are posterior to the nucleus. So they actually create a pneumodissection, so to speak. Which means hydrodissection does not need to be as vigorous. I’m using a Chang cannula here to do my hydrodissection. The goal of the hydrodissection is to separate cortex from capsule, and to get a freely mobile and rotating lens. I like the Chang cannula for that, because as you can see, you can usually engage the nucleus to rotate the lens.
DR MONTERO: Kevin, I already have two questions here. The first one is: What is the best way to mark the patients? And we have a lot of this question beforehand.
DR BARBER: Yeah. That’s a great question. So what I prefer is setting the patient upright in pre-op, before they get to the operating room. Although it can be done in the operating room. And you use a marker and you’re going to make some reference marks at the horizontal meridian. 0 and 180. There are applications for smartphones like toriCAM that can help you do it more accurately, because as you know, when you freehand it, it can be not as accurate. We’re not always perfect. So using something like toriCAM — there are several applications for smartphones that are out there. We can talk more about that in just a moment. That’s a great question. So now we’re gonna go into phacoemulsification. So I’m gonna use a modified stop and chop technique. So I’m in my sculpt mode first. I like doing a sculpt, because it helps me create some space. Now, because of the femtosecond laser, I don’t have to go very deep with my sculpt. I’m gonna go all the way down to the bottom of the trench here. And use equal pressure on both sides to get a good crack. Now we’ll go into the quadrant removal setting. With my technique, I actually lift the nucleus up into my safety zone. So my goal, when I’m teaching phaco, and doing phaco, is to keep my phaco needle in the central safety zone, at the iris plane, and centralized. So that I’m less likely to get myself into trouble. So with this technique, I’m trying to keep my phaco needle as stationary as possible, and I’m gonna use my second instrument to manipulate the nucleus and bring it to where I want it. So we have one half of the nucleus taken out. We’re now going to go for the other half. So I’ll use the same maneuver and just lift the nucleus out of the capsule. And up into the anterior chamber. And try to phaco it in the iris plane. Using torsional. Sure.
DR MONTERO: Another question that we have here is: Why did you choose to make the incisions manually, rather than with the femtosecond laser?
DR BARBER: Great question. Great question. So the challenge I’ve had… With the femtosecond laser incisions… Is that sometimes they are placed more anterior. So instead of the incision, for instance, the corneal incision being right here at the limbus, it’ll be anterior or more centralized. And that poses some problems. One, it throws off your surgically induced astigmatism measurements. And two, it makes the surgery a little bit more difficult. It’s a lot more difficult to get subincisional cortex that way, and it gives you less working space when you’re phaco-ing. So I have found that I can get the incision with my keratome right where I want it every time. So because of that inconsistency, that’s why I choose to do that. Great question. Okay. Now we’re moving into cortex removal. Cortex removal is the coordination of hand movement and foot movement. So I’m going to grab cortex. I’m in foot position zero here. As I move out, I’m gonna grab some cortex with light vacuum and pull it centrally. As I pull it centrally, I’m slipping down on the pedal to increase vacuum. Cortex removal is basically repeating that procedure. I’m going from zero vacuum here centrally, light vacuum under the capsule, and then pulling centrally. While building vacuum. You do not want to keep your IA tip stationary underneath the capsule, as you might grab the capsule inadvertently.
DR MONTERO: Another question that was asked a lot has to do with choosing the patient. What degree of astigmatism can be corrected with the toric intraocular lenses? What is the degree of the astigmatism that can be corrected?
DR BARBER: Another great question. The toric lenses I use are the Alcon lenses, which go from a T3 to a T9, which corrects for 1 diopter of astigmatism all the way up to 4 diopters of astigmatism. Okay. Now we have cortex removal here. We have the 1.2 blade. So you can see that I’ve got some ballooning of the conjunctiva here. Now, normally, that’s not of much concern. However, when we’re going to do intraoperative aberrometry, that can cause pooling of fluid here, which can affect our measurements. So I just made a small little incision in the conjunctiva there, to help reduce that. So now I’m filling the anterior chamber and the capsule with a dispersive. Correction, I’m sorry. A cohesive viscoelastic. So this is Provisc in this case. And now I’m gonna check the pressure with applanation. Great. And when we do intraoperative aberrometry, it’s important we have a moist cornea, we don’t have influence from the pressure from the speculum. And that there’s not excessive fluids. I’m just gonna take a moment to remove the viscoelastic. Any viscoelastic that can be there. Any excess fluid. And now we’re gonna switch to the view for our intraoperative aberrometry.
MS PACHECO: Great view!
DR BARBER: Excellent, excellent. All right. So… Lining up a couple of parameters here, to make sure we have a good view. Which we do. Let’s go ahead and capture. The intraoperative aberrometer is gonna take 40 measurements in less than a second. So it’s very quick. And it’s going to give us our readings. So if we look at the diagram here, the green line is aphakic refraction. That’s the refraction I just did. And the blue line is keratometry. So this can be due to a number of things. It can be due to the aphakic astigmatism, or pressing on the eye, or a number of other things. I did this patient’s first eye and the keratometry was almost the same in both and the same measurement was achieved in her first eye, where we only did a T3. So I’m gonna go with the aphakic refraction here. So in this case, we’re going to pick an 18 diopter lens. That’s gonna get us closest to our target refraction of -2.25. And then we’re gonna pick a T4. The T4 is aimed to treat 1.5 diopters of astigmatism. And as you can see from the aphakic refraction, 1.31 is what we have. So therefore a T4 will be our most accurate or closest toric lens power. So my staff is now preparing that lens. Now that we’ve picked it out. Did you have another question, Dr. Montero?
DR MONTERO: Yes. We have a lot of questions about… What do you do if you have an anterior capsule tear during surgery.
DR BARBER: So if it’s a toric case, I assume that question is specifically toric. I would choose not to put a lens in. This is a one piece acrylic lens. It’s not designed to go into the sulcus. We really need capsular support. So I would go with a three piece, assuming I would have anterior capsular superior, I would put a three piece lens into the sulcus and not attempt to put a toric lens in. And that’s a very important point. We always aim for — our goal is to correct the astigmatism, but if the case does not allow us to do that, then we won’t. So now we’re gonna switch — Lawrence, if you could highlight the iPad view — what I would like to show you guys is the overlay. So are you guys able to see that overlay? It’s a green line and a red line. There over the eye. Okay. So these are the digital markers. So the green line is the digital marker, showing me the preoperative axis of astigmatism. And then the red line is the aura. And they’re lined up very nicely, as you can see. So that’s how I’m gonna line up the axis of the toric lens. I fully realize and understand that most surgeons don’t have the luxury of digital markers or aberrometers in their operating room. So what you would do at this point, if you were doing this manually, is you would have here 0 and 180. You would have your marks. You would use something like a Mendez ring that gives you the full axis markings around the limbus. And then you would line your toric lens up that way.
MS PACHECO: A little tip, as we see that lens unfolding. If you have a blanket warmer, you can put the lens in the blanket warmer prior to the case. It softens it up a little bit and makes it a little bit easier to load and to open up.
DR BARBER: That’s a great tip. Because sometimes those lenses take a while to unfold. Which as you know — impatient surgeons don’t like that. Okay. Lawrence, could you switch back to the microscope? So now for my cases, I do Trimoxi. So this is a compounded formula of triamcinolone and moxifloxacin. I inject it through the zonules into the anterior vitreous. My patients do not take postoperative eye drops, because the antibiotic and the steroid are placed in the eye, and because they’re placed in the vitreous, there’s a depot effect of slow release of about 6 weeks. It offers better protection against endophthalmitis. And in 95% of my patients, there’s no rebound inflammation that requires topical steroid treatment. So it’s a really good way of providing the medications that patients need postoperatively. So now I’m just removing the viscoelastic and being sure to go around the angle. In a light colored iris like this, sometimes little pieces of lens material can hide. So it’s good to go around and do that. I’m going to seal my incision. And I’ll reposition my IOL. So when I hydrate, I’m hydrating that internal wound there. It’s gonna give me the best seal.
DR MONTERO: What is the risk of intraocular pressure due to the triamcinolone?
DR BARBER: Great question. Great question. I don’t advocate that surgeons compound these medications in their clinics, in their ORs, and inject them into the eye. This is purchased from a pharmaceutical company that does exceptional quality control. And as part of that quality control, there’s been exceptional titration of the concentration of triamcinolone. They do modifications to the medication. And when we first started using this seven years ago, there were pressure spikes in about 20% of patients. Now we’ve titrated the dose and the volume down to where there’s less than 5% of patients that would have an IOP steroid response from the Trimoxi. I do not do Trimoxi in patients with advanced glaucoma. However, I do feel that it’s better for pretty much every other patient. And I use that accordingly. But it’s a great question. Certainly what we were thinking about when we started using —
MS PACHECO: Would you do a second capture for say maybe postrefractive patients? Or when would you maybe choose to do a second capture before you closed up?
DR BARBER: Great question. When we first had Aura, many of us did that. What we were referring to was after I put the lens in, we can do a phakic refraction. And check to see how much residual astigmatism is there. The problem is that the pressure has to be perfect again. And so most of us realized that we did not get any additional information. Now, occasionally, we can do that if we had a very challenging case, where we really were not sure if we used the right power or the right axis, because the measurements were not very reliable. In those cases, we could. But I think what’s happened naturally is that we’re just selecting those patients out. So, for instance, if I have a patient, whose preoperative keratometry readings don’t make a lot of sense, they’re not consistent, I’m simply not gonna offer a toric to that patient, because I don’t have a high level of confidence that I’m gonna hit the refractive target. So I think just by natural selection, we stopped doing that, because it would take more time than it was really worth. Great question. So we have 5 minutes here while my staff turns over and gets the second patient ready. So we’ll field a few more questions.
DR MONTERO: A lot of questions are about the intraocular lens calculations. If you just do it intraoperatively with the Aura, or you can do it before, especially for our friends that don’t have access to an Aura, for example, how would you do this?
DR BARBER: Great question. So just so you know… The intraoperative aberrometer requires preoperative measurements. That is a large part of how the aberrometer works. So you cannot abandon preoperative measurements. That’s still the biggest part of this. So I think there’s a misconception that intraoperative aberrometry replaces our biometry. It does not. It’s just an extra tool that helps us take one more step towards the Holy Grail or perfection of plano. So we still do biometry the same way. I personally will measure Ks, the keratometry, in three ways. My Lenstar, my topographer, and then I’ll use the digital marker, but I’ve used multiple things throughout my career. So I have three K measurements. I’m comparing the magnitude of astigmatism and the axis of astigmatism in three different ways, and I want those to line up. I want those to be similar. And then I go with my Lenstar readings, and that’s what we plug into the Aura. And then I’m still using my same formulas, and I use two. I’ll use a Holiday II formula and a Barrett Universal formula. Because I like to have two different formulas. Sometimes — for instance in this case — Barrett recommended 17.5. Holladay II recommended 18. So I’ll let Aura be my decision maker. So there’s not one piece of technology or one modality that allows us to turn our brains off as surgeons. And we have to use all of this information appropriately and in its place.
MS PACHECO: What degree of rotation would you have to bring a patient back to reposition the lens?
DR BARBER: Fantastic question. So I don’t think there’s a number. I think that’s more of a question… You know, with patient satisfaction. So sometimes we get fixated on half a diopter of residual astigmatism after my toric implant. Does that mean that I’ve failed my patient? Not necessarily. The patient is 20/25 or 20/30, they might be perfectly happy. This patient is a great example. The first eye, in the distance eye, she’s 20/25. And she’s -0.25, +0.5. So she has half a diopter of residual astigmatism. However, she’s completely happy. Do I have to worry about that residual astigmatism? Absolutely not. Now, there’s a great tool called AstigmatismFix.com. It was created by John Berdal. So if you have a toric patient, and they’re not seeing as well, and they do have weird astigmatism afterward, that doesn’t make sense to you, you can go to that website. It’s free. AstigmatismFix.com. You can plug in all of the information. And it will tell you if rotating the lens would help, and it will tell you how much you need to rotate the lens. So I will use that. If I have a patient who comes back with a level of astigmatism that I was not anticipating, that’s where I go to. I go to AstigmatismFix.com. I will tell you — putting in thousands of toric lenses, I’ve had to go back and rotate less than 5. It doesn’t happen very commonly, which is nice. What would be more common is actually getting the spherical power wrong, more than the toric axis.
MS PACHECO: If you’re placing your incision in the same axis as the astigmatism, does that change your procedure? You could flatten it? Would you change the diopter astigmatism you’re gonna put in the lens? Change your incision? What would you do if that came up?
DR BARBER: Great question. So I think what you’re getting at is surgically induced astigmatism. So as you guys know, as we make an incision in the cornea, with the keratome, that’s going to slightly change the astigmatism. So how do we address that? So I’m lucky. My digital marker takes care of that for me. But where each surgeon can start is determining your own surgically induced astigmatism. And it’s different for each surgeon, based on where you make your incisions. What type of keratome or the size of your incisions. The style of your incisions. All of those factors will come into play. So if you go to ASCRS.org, to the ASCRS website, they have on there a free spreadsheet that any surgeon can download and use, and it shows you exactly how to calculate your surgically induced astigmatism. So I encourage each surgeon who is going to adopt toric lenses to do that. In my case, it’s about 0.25. So a small amount. And I think that comfort trumps astigmatism. So what I mean by that is that I always want to make my main incision temporally, where I’m comfortable. If I bring it up, you know, to an uncomfortable position, more superior or more inferior, just to treat astigmatism, it’s more likely that I’m gonna struggle in that case, and possibly cause a complication. So I would rather do the math and then use a toric planner that tells me how to adjust the axis of the toric lens. To accommodate or to account for my surgically induced astigmatism.
DR JARAMILLO: Hi. Antonio here. There’s a couple of questions about triamcinolone and the antibiotic at the end. Is there any risk of vitreous loss? Do you experience any issues after injecting?
DR BARBER: Any vitreous loss? No. However… There is a learning curve to doing transzonular injections. Could you cause zonular dehiscence? Could you inadvertently inject through the capsule and cause capsular rupture? Yeah, you could. I don’t advocate doing transzonular injections unless you have the opportunity to be trained on that. Although it’s simple, it does require some training. The other modality is you can do a pars plana injection. Sometimes that’s a little safer. Because all of my cases are topical, I don’t use the pars plana. Patients will feel that sometimes. Especially if your patients are blocked, then you can just measure back 3 millimeters from the limbus. And put on a 27 gauge needle and you can inject the Trimoxi that way. To avoid the risk of damaging the zonules or the capsule. Great question.
DR MONTERO: We have another question here. Do you place the intraocular lens exactly on where the astigmatism axis is? Or do you place it with a slight deviation before the axis? As some surgeons do?
DR BARBER: Great question. So when you place the lens in, oftentimes you can leave it about 5 degrees. Counterclockwise. To your intended axis. Because the lens, as you remove the viscoelastic, might rotate a little bit. And so you can always spin the lens clockwise very easily, but it’s a little difficult to go backwards. Sometimes you have to go all the way back around. So I think it’s a great technique and a great idea to leave the toric lens about 5 to 10 degrees counterclockwise or shy of your intended axis. Take your viscoelastic out. And then as you’re sealing your incisions, you can use your BSS cannula to go nudge the lens that last 5 degrees to get it right on axis. So fantastic question. And yes, I advocate that. That technique. It just makes things easier. Because if you have to go and spin that lens 340 degrees, because it rotated too much, without viscoelastic in the bag, that’s… That can be dangerous. So I think that’s a great technique.
DR MONTERO: That was another question. If you remove the viscoelastic from the posterior surface of the lens.
DR BARBER: So I did not in this case, because with the Ingenuity, the visualization is so good, I can actually see the viscoelastic. Earlier in my career, with traditional microscopes, we could not see it. So I would always go under to get it just in case. If you leave the deposit of the viscoelastic there, that can cause rotation of the lens and can also cause anterior displacement, which could cause a myopic shift or outcome as well. So it’s always better to take it out. In this case, I did not, simply because I saw it come out. So I didn’t need to take the additional time or risk, but normally I would say yes. If you’re not sure. And that’s a very easy step. Nudge the lens down, slip your IA tip underneath it, make sure your IA port is facing towards you, or to the side, where it can grab the capsule, and do a slow build of your vacuum to remove the viscoelastic. If you’re using cohesive, it should all come out very easily. Okay. I was about to say our second patient’s ready. So I’ll go ahead and scrub and get ready. And you can save that question that you had there, Lori, for right after this case. And then Dr. Montero can give us just a little description on what we’re getting into here.
MS PACHECO: Before we start the second case, just a tip for everyone. When you’re using intraoperative aberrometry, is your IOL inventory — you have to have a really good inventory of IOL because that machine can tell you — you could be going 3 diopters up. Rule of thumb usually for me is to order 3 diopters up and 3 diopters down, in maybe half diopter increments to have on inventory. Because the machine could change the diopters of astigmatism on you as well. You could go from maybe a T3 to say a T4. It can do that as well. So just make sure you have a good supply of inventory in your OR. And with that, also be sure — you could have up to 20 IOLs in your OR. On standby. That you could use. So with that, also double check and triple check what you’re putting in the eye. Because you increase the risk of wrong IOL when you have that many IOLs in your OR.
DR BARBER: Lori, that’s a great point. Before intraoperative aberrometry, I would pick my lens preoperatively, and we would have one lens in the OR, and that’s the lens that’s going in. Now about 30% of the time, my toric IOL choice will be changed by aberrometry. Not by much. It will go from a T3 to a T4 or an 18 diopter to an 18.5 diopter. But you know, those little incremental changes are what refractive cataract surgery is all about. We’re trying to get those last remnants of astigmatism and spherical correction reduced as much as possible. But that is a great point. There’s a little more hassle in the OR. Because you do have to have a big pile of lenses available. Instead of just one. Okay. Lawrence, if you’ll spotlight the microscope view again… Do you guys have a good view of the eye here?
MS PACHECO: Yes, looks great.
DR BARBER: Okay. So what you’ll notice… Is that this is our MIGS patient. This will be a manual surgery. And there’s somewhat of a small pupil. This patient does take tamsulosin. So we’ll most likely use a Malyugin ring here. Maybe I could do this case without a ring. But what I’ve noticed is the pupil never gets bigger when you do a case. It only gets smaller. So even if you have a question about… Should I deal with the small pupil, the answer oftentimes should be yes. So I’m gonna try a little epinephrine and lidocaine, intracameral here, to see if it gives us any more dilation. And of course, we can use our dispersive viscoelastic here. The patient does have moderate glaucoma. He’s taking two drops. His pressure has been in the low 20s, on two drops. So this is an ideal MIGS candidate. So I’ve done my complete viscoelastic. Here. Again, same technique for making a primary incision. When you have a potential floppy iris, you might consider making your corneal incision length a little longer. Just to help prevent iris prolapse. So this is a Malyugin ring. I’ll use my second instrument to help it through the primary incision. Some of you might say… Oh, you don’t really need a ring. And that might be true. But again, I have the luxury of knowing that I needed one. So I got all four eyelets on the iris during implantation. That doesn’t always happen. Sometimes you might just get one, and then you go in with your second instrument to position the others. You just want to be careful with the anterior capsule, that you try not to tear or damage the anterior capsule. Now I’ll make a manual capsulorrhexis. I start centrally. I puncture through the capsule, and then I move out peripherally, and lift up. As I lift up, it creates this flap. It’s now very easy to grab. I’ll now walk it around. Taking my time to regrab. I’ll usually regrab three times. My average capsulorrhexis. However, if I need to grab more, I will. So I’ll grab here. And again, walking around, striving for approximately a 5 millimeter capsulorrhexis.
MS PACHECO: And so the audience knows, he is sitting superior. That’s just one of the questions that comes up. So he is sitting superior.
DR BARBER: That’s right. Thank you. All right. Hydrodissection here with the Chang cannula. It also allows you to hydrodissect subincisionally. Which is nice. Because the subincisional cortex is what gives us the most trouble, sometimes. So being able to start your hydrodissection fluid wave there. Sometimes has benefit. What I just demonstrated there is a push/pull technique. Sometimes if the lens won’t rotate, you can lightly push it to try to separate any fusions between the cortex and the capsule. All right. Now we’ll go into phacoemulsification. So I always check my sleeve. My irrigation before I go in. There we go. About 1 millimeter of metal showing on my phaco tip. And I want the irrigation ports 90 degrees away from my bevel. Okay. So I’ll clear out some working space here, to remove a little of the viscoelastic. Here if you go right into phacoing viscoelastic, you can cause occlusion in your phaco needle. And I’ll create my central groove here. When we crack, we can go all the way down to the bottom of the groove and apply equal pressure on both sides. Using the same technique, I’m going to… You should be able to see the phaco parameters. So the quadrant removal. Higher flow. Higher aspiration. Higher vacuum. And we’re gonna use burst phaco energy, not constant phaco energy, as we do with sculpt. I’m using mostly torsional. So I’m using the Centurion machine made by Alcon. This has torsional capabilities, which have some safety profiles, compared to longitudinal. Okay. So now I’ll see… If I can rotate this nucleus. Around to the other side of the capsule. So it’s directly across from my phaco needle. And then I can lift it up easily. Placing it in the best position. And just eating the nucleus, as it comes to the phaco tip. Now I have a fairly large epinuclear plate. So I go to my epinuclear setting. I don’t always do this. Very little phaco power. Much lower vacuum. So things move slower. I’m still gonna try to stay as central as possible. And I can use my second instrument again to help tease some of that epinucleus away from the capsule, into my central safety zone. In that case, if it’s not coming, I’m not gonna go after it with my phaco needle right now. I don’t think it’s safe to be going out underneath your capsule with your phaco needle. So I’ll just switch to my irrigation/aspiration. I try to take the epinucleus out that way. Grabbing the cortex, it helps bring the epinucleus with it oftentimes. Whereas when you grab the epinucleus, sometimes it doesn’t all want to come at once. And using the same technique of stripping the cortex towards the center, being careful not to apply too much vacuum when I’m underneath the capsule.
DR MONTERO: We have a question about your second instrument. What is it? What’s the name of it?
DR BARBER: Great question. It’s a Straight Connor Wand. The Connor Wand is very capsule friendly, because there’s a polished spherical ball at the end. And so that’s why I feel comfortable with my technique using it beneath the nucleus. Going underneath the nucleus. To lift it up. Obviously you would never try that with the horizontal or vertical chopper. That does have sharp edges that you wouldn’t want to get close to the capsule. So especially for beginning cataract surgeons, the Connor Wand is a great instrument, because it is so capsular friendly. Certainly there’s a learning curve of learning how to use a second instrument using your non-dominant hand inside the eye. You can see this is a little bit of a stubborn epinucleus. I’m going in between the epinucleus and the capsule. And I just lift up. And then try to vacuum… I’ll probably vacuum once I’m up into the anterior chamber. Again, protecting my capsule. Okay. Fantastic. I also come off of my irrigation before coming out of the eye, when I have the small pupil for floppy iris. And that’ll help keep the iris from prolapsing through. The only reason the iris would prolapse through your wounds is if you create a pressure gradient. If the pressure is higher in the eye than it is in the atmosphere, that’s when the iris wants to come out. So coming off of your irrigation before you bring your instruments out of the eye — that’s a really good practice. So this is a monofocal lens. It’s a preloaded lens. So it’s a plunger type. Injector. Not a dial. So I inject that… Right into the capsule there. I’m using my second instrument to help guide it right into place. Position it centrally. All right. So now we’ll go ahead and switch to the MIGS procedure. So Lawrence, if you wouldn’t mind spotlighting the iPad view again, I would just like to show how we do that. So the first thing I’m gonna do is I’m gonna rotate the microscope approximately 30 degrees towards the surgeon. And then I’m going to take the patient’s head and I’m gonna rotate that approximately 30 degrees away from the surgeon. And then I will refocus my microscope here. So by 30 degrees with the microscope towards the surgeon, the patient’s head 30 degrees away, that should give us a great gonioscopic view. So the next thing I’m gonna do is fill the anterior chamber with a little more viscoelastic, just to open up that angle, to give us the best view possible. I then will put viscoelastic actually on the gonio prism itself, on the bottom of the gonio prism. Especially if viscoelastic is a premium and you don’t have a lot of it. You’ll use less if you put it on the gonio prism. All right. We can, Lawrence, go back to the microscope view. This is the Kahook dual blade. This is the new version. I’m gonna put that through my primary incision. I’ll then place my gonio lens… On the eye. Real important not to press down with the gonio lens. Now, you can see spots of blood. That clearly delineates where Schlemm’s canal is. So I’m gonna engage the trabecular meshwork right there. And I’m gonna progress forward. In there. I’m gonna come back this way. So this is what’s called an outside-in technique. You’re gonna go — the outside on both directions. And then you’re gonna try to bring — meet them in the middle here. There’s not a very pigmented trabecular meshwork. It’s a little harder to see. Can I have you look at your left shoulder for me? That’s great. So sometimes asking the patient to position — I’m just doing this to try to show a little bit better near the angle. There we go. So you can see we’ve made our trough here. And here. And then oftentimes we’ll have a tag of trabecular meshwork, and we’ll try to amputate that. Oftentimes, you’ll have reflux of blood from Schlemm’s canal into the anterior chamber. And that’s perfectly fine. Okay. So you can see — fairly simple. We’re aiming to do 2 to 4 clock hours. So now I’ll position the patient back into the neutral stance here. So that we can finish the case. I’ll zoom out just a little bit. So again, trying to get about 2 to 4 clock hours of treatment of removing that trabecular meshwork. So now I’ll go ahead and place my Trimoxi. This patient has a mild to moderate glaucoma. So I’m not terribly worried about an intraocular pressure spike. His optic nerve is 0.65 cup to disc. So again, going through the zonules, injecting 0.15 milliliters of the Trimoxi… And now I will remove the Malyugin ring. I wait to do that last, because it’s important when you’re doing the Trimoxi injection to visualize your capsular edge. So that’s why I’m waiting until the very end here, to take out my ring. So I’ll just disinsert. Each of the four eyelets from the iris. You certainly can use the injector to remove. Or you can pull it out that way. I would probably recommend using the injector to remove it when you’re learning, if you don’t have a lot of experience with the Malyugin ring, because that is a little easier and safer. Now I’ll go to my viscoelastic setting. Which just has higher flow and vacuum. And remove all of the viscoelastic. A little nudge underneath the lens, lift it up… Lightly vacuum to get the viscoelastic out from underneath the lens. And then reposition the IOL centrally. And again, coming off of irrigation, as I come out… And you see the iris stays inside the eye, nicely. Not trying to prolapse through our incision. So I’m gonna again hydrate the primary incision here. Then hydrate my paracentesis. Reposition the lens. And we will be finished. The eye is a little soft. Let me check. A little more BSS. Now, if you get hemorrhaging from doing any MIGS procedure and it’s a lot, you can actually irrigate it out, and you can actually increase the intraocular pressure for a few moments. And that will tamponade the bleeding. Obviously you don’t want to do that for too long. But that’s just a trick. You can, if you do have more bleeding. Okay. That concludes our second case.
DR MONTERO: Okay, Kevin. We have some questions about the Malyugin ring. There’s a lot of questions on why did you use it on this specific case. Where it seemed like the dilation was so-so.
DR BARBER: Great question. And I think that that’s… I think that that’s a question that I have to ask myself often. Because you have cases like this, where a patient takes a medication that’s known to cause floppy iris. And the dilation is moderate. So could I have done that case without a Malyugin ring? Probably. However, I had done his other eye already. And I had trouble with the iris. And I ended up using a Malyugin ring. And I would rather — I feel very comfortable putting a Malyugin ring in, and I think that’s easier, especially if I’m gonna be working in the angle, doing more than just a simple phaco. We’re gonna be in the eye longer. And as you know, the longer you’re in the eye, the more the pupil can constrict. So in that case, it was questionable. But I decided to make it easier on myself, just holding the pupil back. I think if I was not using that case for this streaming event, I might have tried it without. But that’s a question that each surgeon always has to make at that time. And I would say especially earlier on in your career, if you have access to the rings, I would use them. Because it makes the case go so much easier. It keeps your stress and your anxiety level down. And allows you to perform the surgery well. When you don’t use a ring, if that pupil comes down, you’re more likely to have capsular rupture or capsular problems. You’re more likely to leave lens material in the eye. A host of complications can occur with a small pupil, as we all know.
MS PACHECO: Would you ever remove it before the MIGS procedure? You removed it after. Is there a reason why you did it after and not perfect?
DR BARBER: Absolutely. The only reason I did it afterwards is because I needed to put my Trimoxi in. And putting Trimoxi in with a small pupil is very difficult. Because if you can’t see your anterior capsule edge, you could inject the Trimoxi right into the capsule, or even rupture the capsule. So that’s why in my particular technique, when I use Trimoxi, I would be more inclined to leave it in ’til the end. If you’re not doing Trimoxi, absolutely. I think it’s perfectly fine to take it out at the end. After you’ve put the lens implant in. And that might even make your MIGS procedure go a little easier. So that’s perfectly reasonable.
MS PACHECO: Going back to your first procedure, Dr. Barber, one of the questions is: What would be the next step if the patient is just not happy? Not satisfied with their vision? What would you do next?
DR BARBER: Yeah, with the toric lens. The dissatisfied premium patient is kind of a whole education in and of itself. And part of that is psychology. And part of that is medicine. And so as far as the medicine part of it, I think you take the objective information. The first thing that I’ve learned — that will make a refractive patient unhappy — is if they have refractive error. So if they come out a -1, +1, and you were aiming for plano, they’re probably not gonna be happy. So you have to have ways of dealing with that. If it’s an axis issue, you can rotate the lens. If it’s a spherical issue, you can exchange the lens. That’s a skill that each cataract surgeon should eventually become comfortable with. To correct the refractive error. You can do laser correction. You know, you can do things like PRK. That would be very common. Not everybody has access to that. I don’t tend to use that terribly often. We try to be as accurate as we can with our measurements and IOL selection. And the other part to that is preoperative counseling. When I tell patients who are going to receive a toric lens, I say: I get you to 20/30 vision or better, 84% of the time. If I can get you to 20/30 or better, you’re probably not gonna wear glasses, and you’re probably gonna be really happy with your vision. But there’s a 16% chance that we’ll be off a little bit. So patients, if they understand that up front, and please don’t use my numbers. You need to use your own numbers as a surgeon. But I think part of treating postoperative refractive error is the preoperative counseling that you give them. And so making sure they understand that this is not perfect and we don’t always have 100% chance of reducing their dependence on glasses.
MS PACHECO: Does your Trimoxi affect the patient’s vision the next day?
DR BARBER: It does. It causes a lot of… As you know, it’s very cloudy. It takes about 3 days to dissolve. So for the first three days, patients have large floaters, usually in the superior. I inject it inferior, so they perceive it superior. So they’ll call it “tree branches”, is what they usually call it, and it’s large floaters that last for three days in their superior vision. And we consent them for that and warn our patients of that, so that they’re expecting it.
DR MONTERO: And there’s another one here. If you could comment on the difference between this Kahook dual blade and the original one. Are there any changes?
DR BARBER: So the one I just used is the newest one. It’s called the Glide. This is only my third time actually using it. They made a tighter taper. So the dual blade is still there. But it’s designed to be more efficient, to cut the trabecular meshwork more efficiently. And I do believe that’s true. As you just saw with the case, there’s no resistance. I remember when I first started doing Kahook blades, I would rotate the Kahook in the trabecular meshwork, the whole eye would rotate, because there was resistance. Part of that is technique and part of that was the first generation of the blade. But now there’s no resistance. It’s like cutting butter. So efficient. So I’m excited that New World Medical is rolling out an improvement on an already great product. And I think the Kahook blade for goniotomy is something that can be used globally. It’s fairly low cost compared to lots of other MIGS procedures, and it works really well. And as you saw, skill-wise, technically, it’s something that’s easy, I think, for surgeons to add to their skill set.
MS PACHECO: Would you ever consider using intracameral phenylephrine?
DR BARBER: I injected it quickly, so you might have missed that, but I did. I had a combination of lidocaine and phenylephrine that was injected, to try to help with… What I will notice is that will help initially. If you’re gonna be in the eye longer than about 5 or 6 minutes, it starts to wear off and the pupil slowly starts coming down. So knowing that this was gonna be a slightly longer procedure with MIGS, again, was why I chose to go with the ring. Absolutely, if you don’t have access to a ring, but you have phenylephrine or a dilating agent, I would use that.
MS PACHECO: Do you have a chance of damaging the iris muscles using the Malyugin ring?
DR BARBER: I think so. Yeah. Early on in my career, I actually disinserted an iris root by just trying to remove the ring. So certainly there’s a skill in learning. I think watching videos, trying to get into a wet lab, I know we have wet lab eyes now that allow for pupil rings. So you can really practice with the iris manipulation. So there is certainly some risk involved. But I would say overall that risk is probably lower than trying to do a difficult case with a small pupil. When you can’t see what you’re doing, you’re gonna run into trouble a high percentage of the time.
DR MONTERO: And another question is: What is your opinion about multifocal toric lenses?
DR BARBER: Yeah, multifocal toric lenses. That’s a whole Pandora’s box with multifocal. But having the toric capacity is great. Early on before we had the toric functions of multifocals, the patients I had were usually unhappy because they had residual astigmatism. Now that we can treat that and get them closer to plano, we have happier patients and it opens the door for more patients to be candidates for multifocal lenses. Like our first patient this morning had 3 diopters of corneal astigmatism. We would never offer a multifocal to that patient. But now we can, because we have toric multifocals that can. We use the same principles in toric implantation as you do with a monofocal toric. But you add onto discussions with the patient about multifocal technology.
DR MONTERO: Thank you. And what is your expectation of the KdV effect on the intraocular pressure for this patient?
DR BARBER: Yeah, great question. I will say that all MIGS in my experience is ultimately good and ultimately helps. I think we send a lot fewer patients onto invasive glaucoma procedures like tubes and trabeculectomies, because we’re able to do a better job controlling the pressure in the case. But I will say it can be inconsistent. I have patients who get a minimal response to a MIGS procedure, and they do have to go on to other treatments. But I would say in my experience, probably 2/3 of them will either have a reduction in the drops that they use or stay on the same drops and have a reduction in the intraocular pressure that’s significant, I would say I haven’t done a study on my own patients, but I would say observationally, I’ll see a 2 to 4 point reduction on patients that get a MIGS procedure. It’s not a profound drop you get with more advanced glaucoma procedures, but if you use MIGS early on during cataract surgery, you can lower the pressure a small percentage earlier on in their glaucoma journey, often they don’t have to go on to more invasive care later in their life. So that’s how I think about the application of MIGS.
MS PACHECO: How are we doing on time? Are you good for a few more questions?
DR BARBER: We’ve got two or three more minutes. Let’s grab a couple more.
MS PACHECO: So what’s your experience for refractive — if you have a monofocal IOL and you want to put it in the sulcus, what do you do with refractive surprises?
DR BARBER: So I assume that question means you have a surgical plan maybe to put in a lens in the bag, and maybe you have a capsular tear, and now you’re putting the lens in the sulcus. So the first thing is: You can make the adjustment in the IOL power. Right? So if you know the A constant of the lens that you were going to use, and say… In the bag lens, there’s a 118.4, but now I’m going to switch to a three piece lens and it has a different A constant, you can do a different subtraction to adjust the lens power. It’s usually gonna be half a diopter of adjustment. However, if you have a complete anterior capsule, and only the posterior capsule has been violated, then you can take the three piece lens and capture it in the optic. So the lens itself is actually posterior to the anterior capsule. And then the haptics are in the sulcus. When you do that technique, there’s minimal change to the effective lens position. So the only change you’re making to your IOL power would be based on a difference in the A constant. Okay? So I’ll give you an example. A few years ago, I was supposed to do a toric. They had about 2 diopters of astigmatism. There was a capsular tear. I couldn’t put the toric lens in. I did a math adjustment. I put a three piece lens in the sulcus. I captured the optic. And then I made arcuate incisions on the cornea, postoperatively. In clinic. To treat the astigmatism. And I got the patient — not all the way to plano, but pretty close, and ultimately, the patient was happy. Just because you have a complication in a toric case, it doesn’t mean you have lost all hope. You can still get really good refractive outcomes. You just need to have several different tools to do that. Did that answer your question? I want to make sure I understood that question.
MS PACHECO: That was the question that came up on the chat. But it sounds like you captured it. Thank you.
DR BARBER: Great. Maybe one more question before they have my next patient ready.
MS PACHECO: Sure. Between the Topo, the biometer, the keratometer, which is your first choice to enter in the keratometry formulas?
DR BARBER: Good question. I don’t know that there’s a hard and fast rule across the board. I think it takes evaluation from each surgeon. Because there’s factors involved with the technician taking the test. How reliable the test is. My digital marker is very finicky. I don’t trust the Ks from the digital marker as much as from my Lenstar, which does it in a more reproducible way and faster. So if it does it faster, the more likely we are to get accurate measurements. If the patient is not blinking or moving and that kind of thing. I go with my Lenstar Ks and I’m using my topographer to demonstrate that there’s symmetric astigmatism, and there’s not other forms of astigmatism — it could be a whole nother topic. So in my case, I use my Lenstar Ks and biometer Ks and that’s what I plug into the Aura. However, I wouldn’t say that’s the blanket truth for all surgeons. That has to be individually analyzed.
MS PACHECO: Wonderful. Thank you so much. I think we’ll stop here.
DR BARBER: Okay. Thank you guys. It was a real pleasure. I hope this was helpful for those of you in the audience and I hope you enjoy your morning, afternoon, or evening. Whatever it may be.
MS PACHECO: Thank you so much. Everyone, don’t forget. This will be — I think it takes about 12 hours. But this will be in Cybersight’s library. So going forward, should you wish to see it again, you can find it in Cybersight’s library. Thank you again. Thank you, everyone. Have a wonderful day, as you said, or evening, and happy new year. Thank you, Maria, for helping.
DR MONTERO: Of course, yeah.