This webinar will be largely case- and video-based discussions on the recognition and management of the immediate, short-term, and long-term complications of trabeculectomy surgery. The speakers are at all levels of experience from current fellows to professors and talk about the “pearls”/tips that they have learned over a collective 130+ years of experience managing glaucoma.
Moderator: Dr. Leon Herndon
[Leon] Good morning, good afternoon, or good evening wherever you are in the world. My name’s Leon Herndon, Chief of the Glaucoma Division at the Duke Eye Center. I want to welcome you to our second installment of the Duke Glaucoma Surgery Series where today we’ll be concentrating on trabeculectomy complications. In our first webinar we talked about basic techniques with trabeculectomy surgery. And sometimes those techniques don’t go great all the time. We’ve assembled a panel of experts today to talk you through some of the complications that, no doubt, you will see with filtration surgery.
I want to first introduce our panelists. Pratap Challa is Associate Professor of Ophthalmology at the Duke Eye Center. Divakar Gupta is Assistant Professor of Ophthalmology at the Duke Eye Center. Stuart McKinnon, Associate Professor of Ophthalmology at Duke. Henry Tseng is Associate Professor of Ophthalmology at Duke. Joanne Wen is Associate Professor of Ophthalmology here at Duke.
And our guest faculty, I’m pleased to introduce you to Karim Damji. Karim Damji and I go way back. We did our fellowships together, actually it took Karim two years to complete his fellowship, it only took me one year. But Karim was a fellow at Duke from 1994 to 1996. And Karim is the Professor and Chair of Ophthalmology and Visual Sciences at University of Alberta in Canada. Welcome, Karim.
And Roma Patel. Roma Patel did her fellowship at Duke in 2014 to 2015. She’s an Assistant Professor of Clinical Ophthalmology at UC-Davis and the Chief of Ophthalmology inside the Sacramento VA Hospital. Welcome, Roma.
Also, this will not be possible without our fellows. We have brand new fellows who just started with us a couple weeks ago. James Liu is a fellow working under the Glaucoma Fellowship at Duke as well as Obinna Umunakwe. So welcome to both of you, you’ll be integral in our presentation today.
Combined we have 134 years of glaucoma experience, dealing with trabeculectomies and complications of trabeculectomies. At this time I want to turn it over to Henry Tseng who will be telling us about how we’re going to be able to communicate among each other.
[Henry] Great. Thank you, Dr. Herndon. Welcome, everybody. We want to have a very lively, interactive session. But of course we can’t have hundreds of people talking all at the same time online. So the way the software’s going to work, is there’s a function at the bottom of your screen called Q&A, many of you probably already know about this function. But if you don’t, look down there and there’s a Q&A function. So we’re going to use that Q&A function to allow you to ask questions. Please don’t use the chat function that’s right next to it but use the Q&A.
Between each topic or cases, I’ll try to see if we can answer a few questions. Unfortunately, we might not get to all of you in interest of time. And if you have any questions about how to perform specific steps of trabeculectomy, I’ll have to refer you back to our video from the last session. For this session we’re going to focus on complications of trabeculectomy. Thank you so much for joining us and back to you, Leon.
[Leon] Thank you, Henry. I also want to give a shout out to our supporters at Alcon and Allergan have been very gracious with their support of our program. And this program will go probably two hours. There’s lots of complications, we’ll have case-based discussion. Hang on as long as you can. We have a lot of areas we want to cover.
So we’ll get right to it, as Henry did mention, we will have a link to this program available for all the attendees within a week after this program.
I’m going to turn it over to James to run the slides and between him and Obi, they’ll get us started.
[James] Sure, it will be Obi to kick us off.
[Obi] All right, thank you for the introduction, Dr. Herndon. James and I are honored to be a part of this presentation. I also want to give a special shout out to the folks tuning in from Nigeria.
As Dr. Herndon mentioned, the first session reminded us that the trabeculectomy is not dead. Hopefully we’ve convinced some of you to perform trabeculectomies in the meantime. Today we’ll focus on the postoperative management of trabeculectomies. In other words, how to keep the bleb alive.
We’ll cover topics including how do you rescue a failing trab? What do you do if the trab is working too well? How do you manage patient discomfort or cosmetic displeasure? And how do you keep the microbes out?
We’ll start with the case of a 75-year-old man with POAG in both eyes. He’s already had a trab in the right eye, his IOP is eight in the right eye, 18 in the left. He already has significant visual field loss in the right eye. And his fixation is being threatened in the left eye. Based on the topic of this presentation, you can probably guess that this patient had a trabeculectomy performed in the left eye. Next slide.
And on postoperative day one, the pressure was 23, the bleb was relatively flat and vascular. So this will take us into our first topic which is digital pressure.
[Leon] Let me go back, Obi, I want to ask because there’s a lot of controversy about suture lysis or releasing the suture at post op day one. Divakar, what’s your thought about doing early suture lysis?
[Divakar] I tend to stay away from doing suture lysis on the first day. And that’s just because I think there’s a lot of things that can affect the postoperative pressure on day one. And so I tend to wait until at least the one week visit to do a postoperative laser suture lysis. I also want them to have some chance to get the antibiotics and the steroids on board. And also allow for some healing. And so that’s another reason that I give a little bit of time before I do laser suture lysis.
[Leon] Okay, Obi?
[Obi] This video demonstrates the Carlo Traverso maneuver which is a form of digital pressure where pressure is applied just adjacent to the scleral flaps. And you can see in the video that the bleb elevates nicely. This is an intraop video but this can also be performed at a slit lamp in clinic. So questions about digital pressure. Is there a role for digital pressure in your practice of bleb management? When do you do it? Do you instruct patients to do it? And what are your thoughts on IOP and bleb survival?
[Leon] Karim, what do you do in your practice? How do you milk the bleb along, as in the early post op period and do you have your patients perform this, Karim?
[Karim] Thank you, I do. I basically ask patients to push from below and then push up into the eyeball for about five seconds. I know some prefer pressure from above. On the first postoperative day I’ll often try it if the flap is sticky or the bleb is not elevated. And as long as the patient can do it in a hygienic fashion, and I can teach them, and if it’s necessary, then I encourage them to do it at least four times a day and push for about five seconds. That often seems to get the bleb going quite nicely. And I do think it helps bleb survival for those blebs that don’t seem very functional in the first few days or even the first week.
[Leon] Does anyone else have an approach to their digital pressure?
[Roma] I can chime in a little bit. Like Dr. Gupta, I also do not do suture lysis on the very first day post operatively. I like to have a little bit of flow in the operating room. If on post op day one, I see that the bleb is sticky and flat, as Dr. Damji mentioned, I will personally do the digital pressure and try to elevate that bleb. Also to ensure that there’s no bleb leak on the post op day one.
And then on post op week one, is usually when I’ll do a suture lysis if there’s not good flow and will instruct the patient to do the digital pressure. Again, I agree with the four times a day. I also do an inferior approach. And I definitely perform it a couple times in clinic so they can understand the level of pressure that they truly need to elevate that bleb. Most patients are very reluctant to touch their eye after surgery or won’t push on the inferior scleral bone here. So you want to really just educate them either to use their thumb and really get up on that eyeball four times a day, five to 10 seconds. And I think it’s really important, especially in post op week one through four.
[Leon] Obi, is there any literature that supports digital pressure?
[Obi] Yes, there is. This study published by Howard Kane, and his colleagues, looked at the acute response of IOP to digital pressure. In the study there are 15 patients and the non operated eye was the control. So digital pressure was applied to both the eyes. In this particular study, the technique was having the patient look upward, applying 10 seconds of pressure, then 10 seconds of rest, and then 10 seconds of pressure again. And this was performed by the glaucoma specialist. And what they found was that there was an average of 51% decrease in IOP in the immediate period after pressure. And this effect lasted on average 95 minutes, ranging from 10 to 180 minutes.
[Leon] That’s interesting, Obi. Pratap, how often do you instruct your patients to do digital pressure? Maybe we should have them do it more often?
[Pratap] Yeah, it all depends on the bleb survival. Obviously if the pressure’s quite low you don’t want them pushing on the eye. But it depends on how they look and also how the pressure is. So usually if I want to get a little bit more performance out of the trabeculectomy early on, I have them do it. The one thing to keep in mind is that when can you do it? Sometimes it works, particularly with mitomycin C application for trabeculectomy, it works quite late, actually. Even weeks to months after the surgery is performed, and in some cases a year or two down the road. But the key is that check it in clinic like Roma was saying, and do it in clinic and see whether you expect it to perform or not and to help.
[Leon] Okay, Obi.
[Obi] In this second study actually looked at the long-term effects of digital pressure. It was a different design, there were 29 patients included. The trabs were at least three months old. There were 15 in the treatment group and 14 in the control group where pressure was applied to the cheek instead of the eye. In this particular study, the patients were instructed to perform digital pressure three times daily. And the goal of this study was more so to look at long-term effects, not the immediate effects of digital pressure.
Patients were instructed to apply 10 seconds of pressure, then rest for five seconds, then apply 10 seconds of pressure again to their central cornea through their eyelid. And this particular study found no long-term IOP benefit at one month, three months, or six months of patients performing this at home.
[Leon] In some cases it seems that we’re, as surgeons, are treating ourselves. We feel we want to do something and digital pressure, we think, may be helpful. But in this case perhaps not?
[Pratap] One thing, make sure it works in the office before asking the patient to try to do it at home. So you do the digital pressure in the office and they see the pressure comes down. If it doesn’t come down, obviously, you’re not going to do it again after.
[Obi] All right, getting back to our patient. Digital pressure was performed in clinic and there was no improvement in bleb morphology or the IOP. We’ve already had some discussion of laser suture lysis. So the question is whether to perform laser suture lysis in this patient.
[Leon] If the bleb didn’t budge after pressure, I would say yes. The bleb is already very vascular, you need a very low pressure based on his visual field loss. I’d like to get the bleb up as quickly as possible. I’m not against doing suture lysis on day one.
[Obi] And a quick review of some of the literature on laser suture lysis. It was first described with the use of a lens in the early 1980’s, originally to perform with a goniolens. And of course with later developments more specialized lenses were developed. Next slide.
And this particular study looked at the effectiveness of suture lysis for patients with flat blebs and high IOPs in the early postoperative period. In this study, they performed all the suture lysis between post op day four and post op week three. They looked at 200 eyes post trab and 99 of these eyes required suture lysis again for flat blebs and high IOPs. And at the 10 month period there were similar rates of successful IOP control between the eyes that required suture lysis and the eyes that did not. So essentially, suture lysis was effective at rescuing those blebs that were flat and had high IOP in the early period. The most common complications seen in the study were flat anterior chamber in 13% of patients and bleb leaks in 9% of patients.
For our patient, laser suture lysis was performed on day one. IOP improved to 18 immediately post procedure and as you can see in the picture, the bleb is nicely elevated. And two weeks later the OP was 13 with a nicely elevated bleb.
[Leon] Stuart, let me ask you, you do a lot of releasables. How is this different releasables versus laser suture lysis, is it the same principle?
[Stuart] It is. My general approach is to tie the flap tight so that they don’t have hypotony post op. That’s my immediate post op goal in my trabs. In this case, you can see a lot of heme and that’s usually the case on that first day if the flap isn’t elevated and the pressure’s up, you have this fibrin closing the flap. Despite digital pressure it doesn’t open up. I like to give that a little bit of time to dissolve and liquify and manage them medically as we were before the surgery. Hopefully the surgery isn’t causing any issues as far as elevated pressure.
And as far as releasing the sutures, I usually wait until after the first week if everything else is looking good. And that depends, of course, on how the bleb behaves when you do digital pressure. If that bleb pops open very quickly, then you might want to wait. If it takes a fair amount of pressure to elevate it a little bit on one side, then I might say, okay, let’s actually pull a stitch today and get this bleb up.
As Challa was saying, I really time it on the behavior on the bleb itself.
[Henry] We have a quick question before we move on past the first week of postoperative follow up. I’m just going to paraphrase, but there’s a question about how useful is it to assess vascularity on post op day one? Or is it more useful after post op week one and so forth?
[Leon] Joanne, you want to take that?
[Joanne] Sure, happy to. I think Dr. Damji actually responded nicely online already. But basically I always tend to document and it’s probably a little bit less helpful on your post op day one because there’s typically subconj hemorrhage and things that are blocking your real assessment of it. Certainly as the weeks go on after your trabeculectomy, it is very important to document your vascularity so that you have an idea of how active that scarring process is and so that you can titrate your medical management.
[Leon] Okay, Obi.
[James] So now I’ll jump in. Sometimes laser suture lysis is not enough. And so another potential in clinic procedure that can be done is needling at the slit lamp. This usually refers to cutting adhesions or loculations around bleb or the flap site in order to encourage better flow. So you might have a patient that looks like this picture shown. An instance where you might consider needling. A flat bleb with IOP of above goal and moderate vascularity. This vascularity is highlighted in this red-free image.
We wanted to talk through a few things about the subject. One is whether or not it can ever become too late to needle? So there was a case series in the British Journal of Ophthalmology that suggested late needling was still effective as far out as 30 years after the initial surgery. They had five patients in that series. And post needling all five patients got a moderate reduction in pressure and were less drop dependent afterwards.
There was another paper that surveyed a group of ophthalmologists in the U.K. about their needling preferences. Most prefer to do it in the OR rather than the slit lamp and most also use 5-FU during the procedure. Wanted to ask if anyone here has different preferences for needlings, perhaps is there any time when you would absolutely not choose to needle?
[Leon] Stuart, I know you prefer taking your patients to the OR to the theater for needling. Can you expand on that?
[Stuart] I like to use a 23 MVR blade because it has an edge on both sides and it’s actually meant for cutting as opposed to a needle. If you use a needle you’re really asking for trouble because it’s really difficult to lyse scar tissues sometimes. So that blade has a point and the risk would be puncturing conj as you’re moving across from one side to the other. And I just like to have the control, I don’t want the patient’s head to move during that. If I’m going to do a needling, I really want to do it correctly and as I’ll show in a little later slide, it can be enhanced by an intraocular procedure. So that’s why I like to do it in the OR.
[Leon] This case that James presents, it has a pretty flat bleb, in fact a very flat bleb. I haven’t seen a lot of good success when the bleb is flat. My ideal bleb is a bleb that’s encapsulated, elevated, you might be able to rescue it. But can you speak to that Pratap, as far as bleb that looks completely flat?
[Pratap] Yeah, that is a big problem. So the main site of resistance with the flow is typically at the collagen, which is that thick, thick collagen layer that forms around the bleb. So that’s when you’re needling you want to puncture through that and allow more flow through that outward. And usually when I needle, I do needle in the slit lamp, and then I usually try to puncture in multiple spots and then kind of connect them horizontally to try to get an opening there.
But if the bleb is really flat and the conj is scarred, the fluid just doesn’t have anywhere to flow and then your healing response is already revved up. So particularly if it’s quite injected, which this is injected, it’s probably going to heal relatively quickly. Most of them that are flat are going to have much less success rate so may not be worth doing it. If you do do it, then you have other options of antimetabolites you can, mitomycin, which is one option to try a mitomycin needle. And of course, almost all my needlings I do use 5-FU. Because once you do the needling, you want to slow down some of the healing response that occurs afterwards, particularly with all these growth factors that come from the anterior chamber to stimulate healing.
[Leon] Okay, James.
[James] As was mentioned, one of the potential complications of needling is a leak. Often we can also see them early after trab surgery. So most commonly it’s going to be at the closure sites, either at the limbus or at the suture sites. Here’s a video of what that limbal leak might look like. You can see that slow ooze and the diffusion of the fluorescein. So in these instances, what would our glaucoma specialists prefer to do for management?
[Leon] Karim, what’s your approach to early bleb leaks?
[Karim] Thanks, Leon. If it’s a small leak at the limbus, for example, then I’ll often either put on a contact lens and the size depends on where the leak is. Or cut back the steroid a little bit, maybe put them on gentamicin or tobramycin, which tends to create a little more inflammation than moxifloxacin, for example. But if it’s a larger leak, I don’t hesitate to go back. Like this one looks fairly diffused, it might need a horizontal suture in the center there. And a suture can be very helpful. And some of it depends on whether the patient’s local or from away, et cetera. And if there’s any hesitation because of the geography then I would just put in an extra suture.
[Leon] Any difference in your approach, Roma?
[Roma] No, I actually agree with what Dr. Damji said. I think that you have to look, is it a diffused leak, or is it a focal leak? And those diffused leaks are going to be much harder to manage and definitely we can try a bandaged contact lens. If it’s very focal, then I look in that area to see if there’s any tension or strain. But I definitely give it at least a week or two to try to wait to take it to the OR. I like to see these things heal on their own.
[Leon] What are you doing about your steroid drops?
[Roma] For the first week, I’m going to keep it the same. I don’t want to potentially cause increased vascularity or increased collagen formation at that site of main resistance at the scleral flap. But that week one, then I may consider if it’s a diffcused leak that’s not reducing in size, I may consider decreasing the steroids. But my heart is sunk at that point because any sort of bleb leak that’s diffused does tend to eliminate, well, not eliminate, but reduce the chance of a beautiful bleb down the line.
[Leon] Yeah, we like beautiful blebs, don’t we?
Henry, I think there’s some questions from the audience.
[Henry] Yeah, thanks to the panelists, there’s been some answer online already. But there’s a few others that will be good for discussion. One of the questions is about platelet activated plasma, does any of the panelists use that during needling?
[Leon] I don’t personally, does any of the panelists use that? I definitely use 5-FU as Pratap mentioned. Sometimes mitomycin.
[Karim] I sometimes use TPA, tissue plasminogen activator, if there’s a lot of fibrin in the AC or if I get a sense within the first week or two that there’s a lot of fibrin causing stickiness in that Tenon’s layer that Pratap was talking about, it can be really helpful.
But generally, increasing steroids frequently can do that same thing, so.
[Henry] We have another question which asks is a cystic bleb is too late for needling? Or pretty much have to redo the trabeculectomy, if you have a cystic bleb?
[Leon] Typically with cystic blebs, you’ll also will have this ring of steel phenomenon. I think it’s worth trying needling to sort of break that scar tissue to allow for posterior filtration. No, I don’t think that’s too late.
[Stuart] The cystic blebs probably have the best chance of working after needling. So go for it!
[Henry] It’s always worth a try, right? And here’s another question. What is the role of pressure patching in the management of early bleb leak?
[Leon] Pressure patching?
[Henry] Patching, yep.
[Leon] I used to employ that early in my career but then I found that a contact lens really having the barrier right at the leak site was more effective. Typically my routine is to place a contact lens, I won’t see a patient back for two weeks. Because as Roma has stated, you really want to give this time. If you see the patients back too soon, you don’t know that the contact lens will work. Depending on the area of the leak, the success rate is usually pretty high with a BCL, 70%, 80% success with a contact lens at the two weeks.
[Pratap] And the pressure patching probably works better earlier post op. But later post op where we usually see a lot of these leaks, pressure patching. Because you can really only pressure patch a patient for one to two days and that’s typically not long enough. Where as a bandaged contact lens you can keep on much longer. Patients also hate being bullet patched also. But they can tolerate a contact very well.
[Stuart] I like to reserve the pressure badges typically for those patients with shallow chambers where the leak is actually causing some hypotony. Where a bandaged lens might not get the pressure up, per se. Then you might want to really just tamponade that leak for a few days and get the pressure back up.
[Henry] Few other quick questions and we’ll move on. So there’s a question on if the bleb is just complete flat, I’m assuming just meaning it’s completely failed, would you still try needling or just basically redo the trabeculectomy?
[Leon] I mentioned earlier if it’s flat I really don’t waste my time with needling. I’ve had very low success in being able to rescue that bleb.
[Karim] Just a comment. I like to think through is it an internal block like with the iris or something, is it at the level of the flap, is it external? And so if it’s early on you can logically think through how to reestablish flow. But I agree with Leon, it’s helpful to do a surgical revision if you can’t deal with it logically and conservatively in the first few weeks.
[Henry] And then just one last question before we move on. Unfortunately we can’t get to every question. But this is a good one, what’s your favorite antibiotic regime for prolonged bleb leaks?
[Pratap] Well, you have to cover those common organisms. Staph, strep and H flu. Typically use moxifloxacin, it’s been published a fair amount lately. But most of the DNA gyrase inhibitors will cover them. But also don’t forget that other medications like polytrim also have good coverage for all three of those organisms. Polytrim’s a relatively inexpensive medication.
[Leon] Okay, thank you, Henry.
[James] So we touched on some differences between early bleb leaks versus more chronic late bleb leaks. Late bleb leaks may be a little different beasts over time, you can go from a diffuse bleb early to a more cystic, elevated bleb later on. And those would have more increased risks for thinning, leaking, infection.
In these cases are there any differences in how the management might be from early postoperative bleb leaks?
[Leon] Yeah, I think the success rate is much lower with these later leaks like you’re showing in this picture. They don’t tend to respond as well to a barrier like a contact lens or ointment. So likely these will be needed to be taken back to the OR. but I will still try a BCL, contact lens. Unless a bleb is really elevated, and the contact lens won’t really fit on the bleb, I’ll try ointments, watch the patients closely, but typically these patients are going back to the OR fairly soon. What’s your take one it?
[Pratap] Well, the biggest thing is vascularity, right? If they’re mitomycin blebs that are very avascular, they have a much less chance of healing. The blood vessels are what bring in fibroblasts and fibroblasts start to provide that understructure to let the epithelium to grow over. So if they’re very avascular, that’s a problem. But yeah, I still will try a contact lens. Sometimes they work, sometimes they don’t. If they have a little bit of vascularity in the bleb, they seem to work quite well. But the biggest issue is how vascular the bleb is, I think.
[James] And of course, what happens if we don’t act on these? We can get complications such as hypotony or infection and we’ll see examples of both later on.
After trab surgery, we may also encounter shallow or flat anterior chamber. Broadly speaking we can divide this up into shallowing in the setting of low IOP or high IOP. For low IOP, one of the causes would be bleb leaks, as we’ve mentioned previously. But post operatively, if we overfiltration may do the same thing. So causes for overfiltration may be from a loose flap, exuberant flow after laser suture lysis, or needling. Maybe the patient was rubbing the eye too hard. Or maybe it’s a fine trab and the pressure’s just much lower than expected. In your post operative exam you might find choroidals on b-scan or your dilated exam.
One of the most important exam features that dictate management may be the degree of swallowing. Certainly a completely flat chamber with lens corneal touch would be viewed differently than something where the chamber’s only shallow in the periphery. This is the space classification and it’s often used to describe the varying severity of shallowing.
And so in these situations how’s the management of a shallow anterior chamber going to occur for overfiltration? Do our panelists have any thoughts on these situations?
[Leon] Yeah, before we go there, I think it’s really important, James, you brought up a good point. When we see a patient with a shallow chamber, we need to put some type of parameters to that. If we just say a shallow chamber, you don’t know next week if the chamber’s more shallow or less shallow. So I like using a CAC grading, central anterior chamber depth grading. So you can see how many corneal thickness you can stack centrally. Three corneal thicknesses centrally, two corneal thicknesses centrally, so you can kind of assess how your treatment options are working for our patients. So you can’t just say a shallow chamber, we had to give some gradation to that.
Divakar, how do you handle these early overfiltration cases in your clinic?
[Divakar] Yeah, these can be challenging because on the one hand, you want the bleb to be up. And if the eye pressure’s a little bit low, that might be okay. Because the natural history of a bleb is that over time there’s going to be more scarring and sometimes the pressure will come up. So if the anterior chamber has adequate depth, and my patients are all cyclopleged in the early postoperative period, I’ll actually just caution the patient. Maybe extend their activity restrictions and encourage them to shield their eye to reduce the chance of the pressure going any lower.
If there is, starting from that grading criteria that James alluded to. In phakic patients, I think it’s very important to reform the anterior chamber and that’s just because the lens and the cornea aren’t meant to touch. And that can lead to a lot of complications down the road. So then I will use viscoelastic to refill. Even in a grade two eye, I’m often either going to follow the patient very, very closely, or just recommend refilling with viscoelastic. Because I feel uncomfortable with the pupillary border of the iris touching the cornea.
I will use viscoelastic in certain cases, but oftentimes I want to just watch the patient closely and tell them what’s going on and caution them to the risk of the pressure going too low.
[Leon] Roma, any pearls for reforming the chamber with viscoelastic, particularly in the soft eye in a phakic individual? Can be fairly challenging, I’m not ambidextrous so I use my right hand for both eyes. Any pearls for this procedure?
[Roma] Hm. When you’re making your paracentesis during the actual trabeculectomy surgery, I always plan its location so that it will be facile to inject viscoelastic at the slit lamp if I needed to. So that’s usually done for me at the four o’clock clock hour for a left eye. And for a right eye, I can use my left hand to inject, so then I’ll do it at about an eight o’clock on that eye. Avoiding, of course, any recent keratome incisions from cataract surgery.
And then, you’ll always want to have at least a little bit of deepening. I try, I really don’t want to cause any iris trauma if there’s iris K touch. And so I really want to, if there is an area that is slightly more deeper, I have no problems making a new paracentesis incision to go ahead and inject Healon. In clinic, I have both Healon 10, which is normal Healon, as well as Healon GV. So sometimes it depends on how shallow the patient’s eye is. If they’re heavyset, sometimes I’ll use the GV, of course, far less than I would in terms of quantity than I would with regular Healon.
But you have to take the patient as a whole. Were there any predisposing factors that caused them to have overfiltration? Do you think the overfiltration is going to resolve in the next few weeks? And also, is there any habitous issues that even though they’re following your instruction and they’re not bending over and straining themselves, are they themselves as a person, predisposed to a shallow chamber? So keeping all of that in mind is how I look at.
And in terms of quantity, I just deepen the chamber enough to have about three corneal thicknesses. You don’t want to overdo it. And you really don’t want to put your cannula in too far. I had a fellow go across the anterior chamber and ended up having the Healon go underneath the iris and then that patient had a lot of iris K touch peripherally for a long time, which is difficult and can cause corneal edema in the long run. So you want to just do it right in the center or even just a little bit peripherally. Just to ensure that there’s no lens K touch. And really for me, that’s the big thing, just to make sure there’s no lens K touch.
[Leon] Great points, Roma, thank you. James?
[James] There was a study comparing either AC refill with viscoelastic agent versus surgical drainage versus medical management with topical drops in the cases of overfiltration. And in that study, those who received early surgical drainage tended to have more significant acuity decline compared to the other groups. Refill with viscoelastic trended towards the lowest final IOP in the three treatment groups. And it had relatively minimal visual acuity decline comparatively.
So then moving to the other end of the spectrum, we also have cases of a shallow chamber with high IOP. Pupillary block could certainly be a cause of this. Where you may see a classic Bombay configuration. These you may YAG or possibly do a lens extraction. Aqueous misdirection or malignant glaucoma could occur as well after surgery. It’s generally thought of as an accumulation of aqueous fluid in the posterior segment. It may look very similar to pupil block, but typically it will be more shallow centrally by comparison. You may treat these medically with YAG laser or surgically. This is an example of a patient who had a YAG laser done to break through the anterior hyaloid face. And you can see the before and after where the chamber has deepend nicely afterwards.
And then finally, perhaps one of the most dreaded complications would be a suprachoroidal hemorrhage. They tend to develop after initial hypotony. The thought is that the choroidal fusions that may result can eventually cause stretch and rupture of the bridging ciliary arteries. Which then leads to a hemorrhage and very high pressure. Large hemorrhages may need to be drained, often waiting a couple weeks after the clot has started to liquify. This was a recent case that Dr. Herndon was involved in.
[Leon] I was involved in creating suprachoroidal hemorrhage, I was not involved in draining it. (laughs) Let’s be clear, unfortunately. Yeah, you see why retina folks want to wait at least two weeks for this heme to really liquify. And so did early…
We did rely on our retina colleagues for these last two diagnoses, aqueous misdirection and suprachoroidal hemorrhage. We want to get onto the cases pretty soon, but are there any other questions, Henry? About these recent slides?
[Hentry] Not about the recent slides. I actually want to make a quick comment about aqueous misdirection. I just had a case a couple months ago and we’ll see this from time to time. It’s very hard to recognize it. Because actually, the pressure’s not really super high in these cases. Because of trabeculectomy, you could get shallowing of the lens, and the iris and then you get a nice bleb. But the pressure might be just in the teens or low 20s, rather than 30s or 40s. So be aware of the fact that it may not be super high pressures.
[Leon] Good point. Okay, James.
[James] Okay. So we can jump to the cases now. We’ve divided them up into different categories of complications you might see after initial trabeculectomy. The first set of cases focuses on underfilitering blebs. So this is a 62-year-old white female. She had SLT, trabs that have scarred and encapsulated on both sides, she’s on maximum medical therapy, with five classes including Rhopressa. But the IOP is still above goal and testing shows progression. This is her most recent Humphrey visual field. Pretty constricted with dense field loss. So again, in a case like this, what would be your next step?
[Leon] Karim, what do you do in this case where the patient’s already had a failed trabeculectomy Ex-PRESS? What’s your next step?
[Karim] I typically, if needling and other things we’ve talked about hasn’t helped, then I think one needs to do a trabeculectomy, assuming that was in the superonasal quadrant, hopefully, then you’ve got some virgin territory superotemporally, then one can do a second trabeculectomy there. Or the other option would be a tube.
[Leon] That’s interesting the tube versus trabeculectomy study of yours states that maybe we should be going with the tube. But you would go with the trab?
[Karim] Yeah, either one. I think it depends a lot on the tissue on the follow up. Some patients are not that good at follow up (laughs) and you want to maintain a stable chamber. Let’s say the patient has exfoliation and unstable lens and stuff, it might lean towards a tube. But otherwise, if the tissue’s healthy, a trab with antimetabolite can often work well.
[Leon] What are your thoughts, Joanne?
[Joanne] I also like to know the history of the original trabeculectomy. If the trab worked for a really long time and then the evolution of it slowly let it scar down, I think it’d be worth trying to do a revision, to try and revive that. If they got a few good years out of it, I think there’s a good chance that it could be revised. But like you said, I think if it failed very quickly and patient’s demonstrating a strong propensity for scarring, then I typically go with the TBT findings and move onto a tube.
[Leon] Okay, James.
[James] In this case in the right eye a bleb revision was planned. In the left eye a superotemporal standard trab was planned. And Dr. Herndon, did you want to talk through the differences between why you chose one and other other for each eye?
[Leon] Yeah, I think it’s important to look at the bleb characteristics. I thought that this patient would do well with a bleb revision in the right eye. She’d had an encapsulated bleb and those, in my hand, tend to do well with a revision. The trab bleb in the left eye was flat. So I didn’t think I could rescue the left eye. But that’s the approach I’d taken. It was really important to look at the bleb characteristics, look at the mobility of the conjunctiva surrounding the bleb, as we plan our surgical approaches.
[James] And so we have the case for the right eye which was the bleb revision here.
[Leon] I’ll just walk you through this, I like to make my incision at the limbus. We’ll use lidocaine 2% with epinephrine subconjunctivally. And you can probably appreciate that this is more of an encapsulated bleb. I’m pretty aggressive with my dissection, making sure you keep that tissue plane between the conjunctiva and underlying capsule. We’ll switch over to Westcott scissors. This is lidocaine 2% with epinephrine. Which also can serve as a dissecting medium. It helps to dissect between tissues as well. But we’re pretty aggressive with these revisions. Westcott scissors, I like to use mitomycin as well on these again. Here’s mitomycin being applied. I like to apply 0.2 mls of mitomycin 0.4 milligrams per ml or 80 micrograms of mitomycin. And it’s important to, in my experience, to apply this before you open up the trab flap. To this point there’s still episcleral fibrosis over that trab flap that I’m going to open up again.
Now we’re opening up the trab flap, and you want to get good flow through the sclerostomy and you want to maintain that. You see there’s good flow. Many times I won’t use a suture to close the flap, I’ll leave the flap open as long as the anterior chamber remains deep. And then we close back up with our standard wing suture technique using a 9-O Vicryl. Sometimes a tenonectomy needs to be performed if the conjunctiva is very taut and won’t come forward easily.
Any other comments from the panelists about their approach to their bleb revision surgery?
[Karim] Leon, the principles are the same, but I often use an incision a little bit higher up so that I don’t have to close right at the limbus. I find it a bit easier to close conj to conj under the lid a little higher up. But the same principles apply.
[Pratap] Once you get the flap up, also, I like to go into the AC either from in the AC out or out of the AC in, to make sure there’s nothing obstructing these sclerostomy as well, just to double check it. But you probably did that just didn’t have the video.
[Leon] I think this was an Ex-PRESS shunt so that’s one thing that you can’t be as aggressive with these revisions when you have an Ex-PRESS shunt in the way.
[James] I think this was a standard trab as well, I believe.
So postoperatively was pretty uneventful. Vision stayed about the same 20/25, IOP of eight and it was a diffusely elevated bleb with minimal vascularity. And he is planning for cataract surgery coming up.
[Leon] Good. Success with our first case. So we can stop the webinar now. Oh, there’s more, okay.
[James] I will turn it over to Obi for the next case.
[Joanne] We did have a question about if you don’t close the flap with sutures for your revision, what do you do if the pressure elevates again?
[Leon] that’s tough. You don’t have any sutures to cut to establish more flow. I’ll do a needling in that case. In this case where it was not Ex-PRESS shunt, Pratap was right, I’ll be very aggressive with my needling. Direct the needle into the anterior chamber. But if that fails to rescue the bleb then we’re looking at something else, possibly a glaucoma drainage device.
[Obi] All right, so moving onto our next case. We have a 70-year-old woman with severe POAG in her right eye. She’s monocular, status post enucleation of the left eye due to trauma. In 2015, she had a superonasal trab in her right eye with Ex-PRESS shunt. She’s had fluctuating IOPs throughout the years and in 2018, she had a superotemporal trab, standard trab placed in that eye.
Again, she continued to have fluctuating IOPs and underwent laser suture lysis in 2018. And then a few months ago, underwent bleb needling in clinic. Despite this, her IOP was 30 at a subsequent followup visit. And her visual field is presented there at the bottom right of the slide.
For this patient the decision was made to do an ab interno bleb revision and we can move onto the video.
[Leon] So I’ll walk you through this as well. When I do these revisions, I’ll first give it a mixture of lidocaine and mitomycin C 0.4 milligrams per ml posterior to the bleb. I thought an ab interno revision would be reasonable in her case. She’s pseudophakic, she’s had a standard trabeculectomy. And we’re using a Grover spatula which has some advantages over the cyclodialysis spatula, as it’s longer and it’s got a blunt tip, so you don’t break through posteriorly. You really want to push through that posterior ring of steel. Eventually you’ll see the blue of the spatula showing up subconjunctivally.
One thing I didn’t do in this case, Obi, is do endoscopic guidance. I think it’s important to not go in with a blind pass. But make sure you visualize where your sclerostomy is. And what you’re doing is just sort of breaking through posteriorly to create a new plane.
Anyone else have experience with ab interno revisions?
[Divakar] The only comment I had, in some cases, maybe not this one, but where the bleb is up and you want to do a revision, you can do an ab interno needle revision in the clinic at the slit lamp. And that’s a technique described by Paul Palmberg. That actually has worked really well for me in a couple cases. Where you can bend a needle so that you can put into the superotemporal or superonasal cornea and then direct it towards the ostium.
[Pratap] One thing that’s nice about ab interno is you can really elevate the flap sometimes too, if you get up to the edge of the flap all the way around, you can sort of loosen it up and push the flap up. Which can help with long-term survival.
[Joanne] I’ll also-
[Leon] Go ahead, Joanne.
[Joanne] I was just going to say I’d also consider doing that sometimes if I’m doing a phaco in a patient who’s already had a trab and the trab just looks kind of iffy. You’re already in there, it’s easy to go in there. I was just doing it with a cyclodialysis before that nice instrument came out. Dr. Sanjay Sirani called it “tickling the trab.” (laughs) But we would go in and just break up some of those scar tissues and try to get it working a little bit better since you’re at a little bit increased risk of trab failure anyway from the phaco surgery.
[Leon] Good point. So she’s done well, Obi, do we have any literature of this technique?
[Obi] This technique was first, well the spatula and this technique were first described by Dr. Grover and Dr. Fellman in 2017. This diagram here demonstrates their technique, including the use of a gonioprism to visualize the scerlostomy in this case.
[Pratap] Did you mention post op? I mean, almost all these patients you put on steroids and depending on how much vascularity you have, you want to use more aggressive steroids sometimes. Sometimes you give subconj, depo steroid injection as well. And you already mentioned you use mitomycin. But if you don’t use mitomycin, you can usually put 5-FU or give multiple 5-FU injections post op. But any case, you want to slow down that secondary response that happens to try to scar these down.
[Leon] Absolutely. Okay, Obi?
[Obi] Next we’ll move onto a category of cases we called bleb issues.
And our first case is a patient with bleb dysesthesia. It’s a 64-year-old woman with POAG in both eyes. Status post trab in the left eye and she’s complaining of significant bleb irritation despite frequent lubrication in the ointment. For this patient, the decision was made to use compression sutures and this technique was first described by Paul Palmberg in 1996. And we can move onto the video.
[Leon] This is a lidocaine 2% of epinephrine that we inject posteriorly. You can see how large that bleb is and you can imagine how she’s having some discomfort. We use a 9-O nylon to make three or four figure of eight passes. You want to take a good episcleral bite posterior to the bleb. And so in this case, we’re doing three figure of eight sutures and a slipknot. We are going to tie this very tightly so that you’re really compressing the bleb. You want to lower the profile of the bleb. You want to rotate the knots anteriorly into the cornea. In this case, she’d also had some temporal elevation and I needed to do something about her temporal aspect. So I made a little incision directly into the bleb and we’ll see another technique later. And Paul Palmberg described using this technique for leaks as well. So I use another compression suture temporarily to cover the area of incision, deflation if you will, of the temporal bleb.
But this technique works very well.
What are others doing about their painful blebs? Stuart?
[Stuart] This also works well for that sort of rare bleb that goes 360 around the eye. It may not be particularly painful superiorly, but due to the conj chemosis down inferiorly, the patients are complaining. So if you could place two sutures at either edge, that will localize the blood to the superior aspect and usually take care of that.
[Leon] Does topical therapy often help with this, Divakar? What’s been your experience?
[Divakar] Yeah, I mean, I will try to convince a patient that maybe dry eye plays a part in this. But I haven’t had a lot of success. If the morphology of the bleb is such that it overhangs the limbus or is very large, I have had some patients complain of bleb dysesthesia. And I like this technique, it’s worked well for me to compress the bleb and help with some pain issues related to blebs.
[Leon] Obi, can you go back to the start of the video just to demonstrate the extent of the bleb? Go back one, James.
Yeah, so, again you can’t see my cursor but this is a left eye superior and superior temporal extent and filtration. And these patients often get dellen and dry corneas at the base of the bleb. And that’s the cause of their pain. One thing, so I give them options. I tell them we’ll try this first, it’s less evasive. If it continues to be a problem then we’ll do some bleb shutdown techniques that we’ll talk about later.
[Karim] Leon, what about autologous blood in this scenario. I’ve tried it a few times and occasionally it works. But I haven’t been too happy with it.
[Leon] Funny that you should mention that, Karim, I think we have presented a case of that. I know we talk about our paper that we published, I think Karim you’re on that paper. Several years ago where we used autologous blood for blebs primarily. But I’m not seeing success in dysesthesia. Have you, Pratap?
[Pratap] I mean, not really. I’ve tried it a couple times but it doesn’t seem to change the bleb morphology very much. I think you really have to mechanically change the morphology which you can do with either stitches or excising it like you did in the other. The temporal aspect of the excising or incising a little bit of the conj and that really stimulates the conj to seal down and heal down very tightly against the sclera.
[Leon] One thing I didn’t mention, it’s really important to remove these in clinic at three weeks. If you don’t remove them then they can cheese-wire into the bleb and create all kinds of problems. I tell patients that we’ll do this, you won’t feel great until we remove the sutures three weeks later. But in my experience, these do need to be removed. Obi?
[Obi] Another option for management of oversized blebs is bleb window cryopexy, which was described by Dr. El-Harazi and his colleagues back in 2001. And we want to present an example of that as well. So we can move onto the video.
[Leon] Yeah, so this is one of those 360 degree blebs that Stuart talked about, so where do you place the compression sutures here? All round the eye? No. We make a little incision into the bleb and make a window. In this case it’s temporally applied cryo treatment to really scar down this area. In the paper that Obi mentioned, describes 12 to 13 patients who had great success with this, decreasing the pain, and also maintaining the IOP control.
[Obi] And this is a nice email that Dr. Herndon received about this patient after the compression sutures were placed. The patient was much more comfortable, hates her regular ophthalmology much less now.
[Leon] Yeah, the patient’s going to be really uncomfortable and upset with these irritated blebs in my experience.
Any other thoughts before we go to the next case?
[Karim] I haven’t tried it much but you know for conjunctival chalasis there’s some techniques described where you can do cautery lightly inferiorly, for example. So I wonder whether cautery could be tried too?
[Henry] Also, quick question. There’s a question on if you remove the compression sutures, does the bleb irritation come back?
[Leon] In my experience, typically it doesn’t. This is probably in the 80% success rate, in my hands, as far as decreasing the pain. Sometimes they still have some mild discomfort. But I’ve been really amazed at how well this works.
[Roma] One tidbit that I might add. For the diffuse overfiltering blebs, like both of your cases, with the nice uniform appearance, I agree that the compression sutures work really well. I had a case where a gentleman had a really well-functioning trab superiorly. But there were some cystic areas right at the lid interface, temporally, and it was causing bubbles and a small dellen and he had some irritation. So for that particular case, I did the cryo technique. And I think that worked better because I don’t know if the compression sutures would have eliminated all of that cystic area.
So I don’t know if you want to choose your technique based on the bleb morphology.
[Leon] Yeah, I definitely think that’s a good point when you have those 360 degree blebs like we showed. There’s not a lot you can do other than try to deflate it and scar it down. But the compression suture technique works pretty well with these blebs that aren’t quite as extensive as you described.
James, are you taking this one?
[Obi] For our next topic we have actually a couple of surgical videos. You can move onto the next slide. It’s a nicely narrated video.
[Leon] This patient is an 84-year-old gentleman, who has lost his other eye due to glaucoma. And in his left eye, underwent trabeculectomy some five years ago. He presented to me with complaints of a skim over his vision. As you can see, he’s had extension of the bleb onto the cornea and this bleb, we call accessory bleb, is covering his visual axis. His visual acuity is down to 20/200 in his only eye. His intraocular pressure remains very well controlled at 7 millimeters of mercury, off of medication. So the bleb continues to function very well. This procedure involves simply scraping the accessory bleb away from the underlying cornea. In this case, using a spatula blade or a Tooke blade, and this leaves a large epithelial defect as you see. But this peels back very easily. Only anesthetic that I’m using is a topical tetracaine.
So once this accessory bleb is dissected back to the limbus, we will be able to excise the accessory bleb from the main bleb without causing any leakage. I think the cause of these overhanging blebs is due to the trauma of blinking repeatedly over years and that just pushes the fibrosis or scar tissue over the cornea. But as you’ll see as I excise, this accessory bleb is truly not attached to the main filtering bleb. I use Van Ness scissors in this case to excise the accessory bleb as close to the limbus as possible.
And the patient does very well postoperatively. He retains and regains 20/40 vision over the next few weeks. Once the corneal epithelial defect heals and his intraocular pressure control is maintained in the single digits, again, no leakage with these maneuvers. There’s low excess tissue that we’ll excise in this case.
[Obi] That patient did very well in the postoperative period. We have another case, this time an 86-year-old man with POAG in both eyes. Had a trab in 2007 in the left eye. In 2013, he had a bleb revision with compression sutures for dysesthesia and choroidal fusions. Several years later, he returns for evaluation of an enlarged bleb, where the patient himself is more bothered by the appearance of it than the irritation.
[Leon] Obviously, this anterior migration’s nowhere as extensive as the first case we presented, but we do the same technique of using a spatula, a Tooke blade in this case, to scrape the anterior migration posteriorly. And we’ll excise this right at the limbus. Now the thing that’s different about this case is these can leak. And in this case, there was some leak there. But this is really only three or four weeks ago. And over time, I think the leak will slow. But there’s still a little leak there. He was happy with the results.
Now you may say, why do this if he’s not bothered by pain? I really thought this would be a good approach for him. He’s very vigorous at 86 and he just didn’t like the way it looked. But maybe as I look at the case as it presents itself now, maybe we should not have done that. Obi?
[Obi] Yes, as Dr. Herndon mentioned, this patient has a persistent limbal leak. The case was only performed a few weeks ago so this is an ongoing management process. Patient will follow up soon and if the leak persists, a bleb revision may be considered.
[Leon] What’s your approach with these anterior blebs?
[Karim] Were you asking me?
[Karim] Like you. Basically the indications are important. So I think one has to ideally operate only if it’s causing pain. Some kind of dysesthesia, or astigmatism, vision problem, et cetera. Most actually if they’re small, a couple of millimeters and often they’re dissecting at the level of Bowman’s, tend to do quite well just with lubricants depending on the lid height and so forth. Sometimes if they need more coverage you can drop the lid with a gold weight or some procedure like that and buy some time.
But otherwise, I tend to dissect it like you and it does very well. Occasionally I’ve had patients that have redeloped this, almost like a pterygium with vascularity. And those patients, once you’ve dissected them off, I tended to use fluorometholone on a chronic ongoing basis to prevent recurrence. And that works quite well.
[Leon] Anybody else?
[Henry] We do have an interesting question for the panelists. This question is about for those without access to cryo, for those 360 degree blebs, are there other alternative techniques to handle those blebs?
[Pratap] Yeah, there are. And one thing I like to do instead of cryo, is you can cut a small window out of the conj and then suture down the edge of that conj to the sclera. Sort of in a horizontal fashion, so you do a couple little windows and suture them horizontally. And that really stimulates the conj to heal against the episclera, the sclera, and then limit the bleb flow. So just cutting a tiny little window out from the conj and just make sure you suture the conj to the episclera. The reason you cut the window out is that it really stimulates a lot more healing and forces the conj to grow over the sclera and gets it to really tack down. If you just simply put sutures there they don’t always get the conj to scar down.
[Leon] Okay, Obi?
[Obi] Our next category of cases are overfiltration and leaks. First we’ll discuss transconjunctival scleral flap sutures. This patient is a 34-year-old male with severe POAG in both eyes. He had double tube surgery as a teen. The Ahmed tube was removed in 2017. Currently his vision is hand motion in the right eye, 20/25 in the left eye. And as you can see in the visual fields his fixation’s being threatened in the left eye.
The decision was made to do a trabeculectomy in the left eye. Post op day one, IOP was 22, laser suture lysis was performed and IOP improved to 12. Post op day three, vision had declined to count fingers and IOP was five. And Atropine was added to his treatment regime. And by post op week two, vision was still count fingers and IOP was four and the chamber was reformed by Healon. A few days later vision had improved a little bit, IOP was still low. The decision was made to take the patient to the operating room. And we can move on to the video.
[Leon] Obi, I’ll stop you there and say this was a case of suture lysis post op day one, correct?
[Leon] Okay, all right, as you mentioned with suture lysis you can have complications and this is one of them. But fortunately it was a good outcome. Roll the video.
This is a really nice technique, most times what we’re doing is just replacing the suture that was removed or lasered. You want to make sure you know where the outline of the scleral flap, I used 10-O nylon suture. And it’s really a fill, I give lidocaine 1% for every three entered camerally. Typically all the anesthesia you need. So we’re kind of outlining the trapezoidal flap. Giving some instruction here about where we want to go. This is the suture that was cut with laser. Now we’re just going straight through the bleb and making sure we have a good bite of the scleral flap. And really I teach my trainees about rotating the wrist, you don’t want to push this needle. You want to rotate the needle and take a really big bite. And then we’ll place a 3-1-1 suture to really compress that area.
So we tie it very tightly. And I tell patients that I may be able to do this short procedure or maybe I’ll do a more extensive procedure depending on how the tissues react. In his case, when we reformed the chamber, you could tell there was good firmness to the anterior chamber, there was no leakage there at that one suture. And I felt confident that we would not need to do any more dissension. We rotated the knot anteriorly. But the key is, if you’re not sure, then I don’t want the patient to leave the table with hypotony. So you really want to do what you need to do to bring that pressure up.
[Obi] This patient did very well postoperatively. His IOP ranged from about nine to 11. His anterior chamber remained formed and his vision improved near to his baseline vision by post op month one.
[Leon] Sometimes we’ll place more than one of these transconjuntival sutures. There was one remaining suture that was not lysed. I felt confident that that one would do the job and on the table, as you saw, he did very well.
Any thoughts on anyone else’s approach to this early overfiltration?
[Pratap] tThe transconj sutures are really nice. You just leave them tight and they’ll just work their way into the blep. And after a few weeks the epithelium will heal around them and then you don’t have to worry about infection or anything.
[Karim] Yeah, I would agree.
[Leon] Okay, Obi?
[Obi] So we have a second case involving transconj sutures involving a 75-year-old man with severe POAG in both eyes. You can see the visual fields there. He underwent a combined phaco and trab in the left eye. Post op week two, IOP was 20, and laser suture lysis was performed on the temporal suture. IOP dropped to one with a flat chamber. And the anterior chamber remained, or actually the IOP remained zero to one despite multiple anterior chamber reformations.
So this patient was taken back to the operating room and this is actually one of my early, very early fellowship cases that was done a few days ago. Essentially the same technique that Dr. Herndon just described for that last case, where a nylon suture is passed through the same track as the suture that was lysed.
[Leon] You really can see how soft this eye is, if you just look at the anterior chamber and the way we palpate the globe.
[Obi] Suture’s tied down tightly and anterior chamber remained formed at the end of the case. Post op day one, which was two days ago, the IOP in this eye was 40 with no improvement with digital pressure. Laser suture lysis was performed of the nasal suture, so the opposite suture. IOP came down to 20 and we’ll follow up with this patient and see how that goes.
[Leon] So, this is why it’s important to have a good relationship with your patients. If you tell them you need to cut the stitch again and you say, well, that’s what got me the problem the first time. But the pressure’s 40, you can’t let him leave with that. So we did cut the suture, we did not cut the suture we just placed, but the other suture that wasn’t touched was the one that was cut and the bleb came out nicely and I think he’ll have a good effect.
Any other comment, any questions, Henry?
[Henry] Actually, there was a question on that and you just answered it. It was a question on if you had a transconj suture and IOP goes up, what do you do? So that was perfect timing.
[Leon] Yeah. Now if I hadn’t done suture lysis to both sutures, then I would have placed two or maybe three transconjunctival sutures, and just cut them as needed. Okay, Obi.
[Obi] This technique was described in 2004 by Dr. Shirato. It was a case series of 10 eyes where a transconj suture was placed. IOP increased from an average of 2.6 to an average of 8.8. Dr. Shirato did note that there was a small leakage at the suture points but that this leakage spontaneously resolves within hours to days.
[James] Okay, so we’ll move on to case six. This is a 39-year-old-
[Henry] Can I just interject, there’s one more question about the transconj suture and then we’ll move on. There’s a question on how long do you leave the suture, especially if the IOP is well controlled?
[Leon] Yeah, as Pratap mentioned, this suture similar to the compression sutures will erode through the bleb and it’s amazing when they integrate into the bleb, there’s no leak and you follow these patients a month, two months after and it’s like you then go through the conjunctiva that you did an open revision. I don’t remove these. They just work themselves safely into the bleb.
[James] Okay, back to our next case. Which is a 39-year-old with JOAG who’s had trabs about 10 years prior. Unfortunately, they lost vision in the left eye and is now monocular. At the time of presentation, both eyes had avascular cystic blebs that were briskly leaking. The right and only seeing eye, was hypotonous at three. Here’s their OCT with some evidence of hypotony maculopathy. And then this is their 10 dash two.
Again, a summary, 39-year-old very advanced disease, what’s next for this patient?
[Leon] Stuart, what is your approach to a leaking bleb such as this.
[Stuart] Well at this point I would assume we’ve tried all the conservative things. Augments, contact lenses, and given the monocular status and if that was the situation, I would recommend an actual bleb revision and that would require a trip to the OR to bring conj forward.
[James] That was what was planned, here’s the surgery itself.
[Leon] Another really extensive bleb, thin walled, again this bleb, you can see how soft the eye is when I’m trying to place my traction suture. It’s really hard with these thin conjunctiva cases to close a leak, primarily. And this eye did not really conform to a contact lens, the bleb was too large to allow the contact lens. So our approach is, and we’ll show some literature on this, is an excisional, or we call it excision and pull down. You can see the leak there at the limbus.
Maybe we could have gotten away with a horizontal mattress suture? But we did more of an extensive. We inject lidocaine directly into the bleb and we worked so hard to get this bleb to work, years ago, her glaucoma surgeon at the time but now we’re going to destroy it. So I’m showing there’s good mobility of the conjunctiva, this is crucial to assess this in clinic before the surgery, because in my approach you excise the ischemic bleb and you need to have enough tissue to bring forward.
And then we’ll excise, I teach the fellows to just cut it all out. Just cut all that ischemic tissue out and some of us may have a different approach, and I’ll be curious after we narrative this what others would have done differently. But you don’t often know what you’re going to see on the trap flap once you get there. I did not do this original trab, that was done 2003, James, I think?
[James] Yes, that’s right.
[Leon] Yeah, so, there’s a question about Tutoplast patch graft. Yes, so a pass graft could have been used at this case, we do have that on a later case. And so just excise, we can probably speed this up a little bit.
[Stuart] Yeah, occasionally you’ll find a bleb that doesn’t really look too bad, it’s not too elevated, and sometimes you can excise conjunctiva around it, but leave a fair amount of the preexisting bleb if you think it’s still functioning. It would be to either use absolute alcohol to kill the epithelium that might be overlying that avascular bleb. And a combination of cautery, perhaps, to shrink it a little bit. Then you can actually overlay the conjunctiva over the preexisting bleb and that can work occasionally.
[Leon] So when I get in I see this pretty much macerated flap, is an open sclerostomy, essentially. That’s a huge excision that we had to do. What’s the thing, Stuart, you let patients know before this?
[Stuart] That they’ll probably have upper lid ptosis and need to schedule.
[Leon] Not probably, they will. (laughs) You can count on it. So you definitely have to prepare. And in this case I did use mitomycin. And it’s kind of tricky, there was a leak, sometimes I’ll put a little suture through the flap to close it before we apply mitomycin. But my thought is in this case, mitomycin, that’s back in the day when we just used single sponges. That this tissue might have not been exposed to mitomycin. And this is a really key for me, I found that this will allow, if you have trouble bringing the conjunctiva forward, you really want to do a tenonectomy, the Tenons sort of keeps the conjunctiva tethered posteriorly. And once you release this, you’ll see how easily conjunctiva comes forward. That’s a pearl for anybody doing these approaches.
Comes forward nicely. Then use your standard conjunctiva closure technique.
[Stuart] For these I’ll usually do a double wing suture with a running of the dog ears.
[Stuart] The conj dissection really needs to be extensive. It’s usually much more than you think for that conj to come up easily.
[Pratap] Yeah, once in a while you have to rotate a little conj over z plasty, rotate over from another quadrant if you don’t have enough space. Particularly if it’s tight on the lid.
[Henry] So there’s a comment from Dr. Gayle Howard. One could consider relaxing the incision in the fornix to loosen the pull on the upper lid. So thank you for the comments.
[Leon] Thank you, Gayle. So the bleb came up nicely and we’re happy.
[James] The surgical technique that we just saw for excisional bleb revision was published a few years back in Journal of Glaucoma, by Dr. Myers and others including Dr. Herndon here. In that study they followed 16 patients during a three year period and showed that surgical revision produced very promising results. Average IOP increased from 3.8 to 11.9. Most had at least two lines of improvement in their visual acuity. There were a handful of patients with post op leaks, but all but one resolved on their own. In that paper they do warn about causing too much tension during the conj closure, as was mentioned during the video itself. We talked through a few of the tactics that might relax the tension and reduce the risk for ptosis and diplopia.
For this patient, back to our case, day one he was doing all right. However at month one the bleb was more flat, more injected. There was a trial of steroids and then surgical revision was done as well. But these efforts to revive the bleb didn’t seem to work very well and he eventually required a tube shunt, he’s in his early postoperative period now.
The next case we have is a 65-year-old with severe open angle glaucoma and hypotony maculopathy. Severe in both eyes and he had trab surgery in 2018 with hypotony that resulted. Compression sutures were done at that time but they didn’t seem to have much effect on raising the pressure. And the vision, unfortunately, went down as a result. Eventually he was referred to Duke Eye Center for his persistent hypotony. At that time visual acuity was 20/200 and the IOP again was four. This was his most recent field, which is just kind of blacked out. Not terribly helpful there. And this the OCT showing some of that maculopathy. In this instance, what might be your next step?
[Leon] So the question we get often asked is how long can hypotonous maculopathy persist before maybe you shouldn’t try to revise it? This has been about, he had surgery done in Chicago and New York and seen some of the country’s best glaucoma specialists. But he had been hypotonous for almost two years by the time we met him. Divakar, what’s your approach to the patients who have had hypotony? I know the books say you have six months to repair this, what’s your approach?
[Divaker] Yeah, I think there’s been several case studies and case series that have shown that even patients that have had hypotony maculopathy for several years can regain vision after a revision, or if their eye pressure were to come up. So I counsel patients that there’s risk to surgery if they pursue that route. But there are chances and it’s been reported that they could regain some vision. And for some patients the vision loss from the hypotony is so great that they’re willing to go with the risk. And so I do offer them some hope that their vision can be improved with revision surgery. And I have seen that in my own experience.
[Leon] Anybody else have a different approach? Okay, James?
[James] So the decision was for a bleb shutdown with a clear path at the same time. This is that surgery here.
[Leon] Yeah, so sometimes you get to the point that you’ve got to shut the bleb down. There’s no real other way in my experience that I’m going to transconjunctival suture would have worked. We opened up the flap and you can see there’s a gaping wound there. So perhaps we could have tried a transconjunctival suture? But I felt with the extensive two year history of hypotony maculopathy we need to be a little more aggressive. So in this case we used Tutoplast pericardium and really sutured this tightly using a 7-O Vicryl over the sclerostomy and we placed the suture in three points. And have a really tight, tight seal.
But, of course, if you shut down the bleb, you’re going to be dealing with pressure issues. Could you pause it there?
I guess we have a poll about who would have just shut down the bleb and reevaluated for a second procedure? Stuart would you have just stopped after you shut the bleb down and see what happens, or would you have been aggressive and done something else?
[Stuart] Probably in this situation would have shut the bleb down and watched the patient. Let the eye repressurize, and hopefully that repressurization if it’s not too extreme, will help with the maculopathy. And then deal with the potential elevated IOP secondarily.
[Joanne] Yeah, similar. I think depending on how severe and advanced the glaucoma was, how much I thought they could tolerate some pressure spikes or fluctuations. I probably agree with Stuart, shut it down, and watch closely, and see what the pressure does. I suppose if I did something like a ClearPath, I may tie it off a little bit more permanently with a ripcord and then it gives me an option to open it up later if I need it. But if that site’s still trickles or still has some kind of aqueous outflow, you may not need it.
[Leon] Roll the tape, James. We’ll be talking about tubes in our next installment next month. This is a ClearPath 350, a newer medical valveless tube. And we really want to keep a long bevel. I like to use a 22 gauge needle, many of us use 23, but I use 22 gauge. The thing that’s different about this case. Many times I do venting slits or a wick technique. But I do still think there’ll be flow from the original bleb shutdown so I’m not as aggressive with trying to vent the tube. And this kind of conjunctiva defect that we’ll close with 😯 Vicryl on a BV needle.
[Pratap] And I’ll just make one comment. It’s easy to be a backseat driver, but if you’re got a lot of flow through the trab flap, just putting a stitch there may have been a reasonable thing to consider and then just see if that would control the pressure. The other thing is when I put the, I usually use scera to shut these down. I use 10-O nylon sutures because then if I want to get more flow, I put four. I put one, two anteriorly, and 2 posteriorly just like as if it’s a trab flap almost, and then I can lyse those using a laser if I wanted to get a little more flow in some of these. That’s one consideration. But like I said, it’s always easy to be a backseat driver.
[Leon] Yeah, yeah, that’s a good point.
[Roma] Would you have considered trying to do a Tralla run by pressuring the eye with some viscoelastic to see if the vision improved?
[Leon] I think we’d done that or he did that with his docs in Chicago and New York before he came to me. But I think it’s a good point to see if there’s any vision returned. But the thing about this when you reverse hypotony it can take weeks before those choroidal folds sort of iron out. James, how did he do?
[James] So this is his postoperative course. Initially we saw him in November, several months later after the surgery, this was his macula afterwards. His vision went from 20/200 to 20/25 so very good improvement there.
Briefly to touch on this topic of hypotony maculopathy, since we’ve seen it a couple times already. It was originally described in 1954. I tried very hard but I could not fight the original German text. I also can’t read German, so I don’t think it would have mattered.
But more recently there’s been some studies, one that looked at hypotony maculopathy in the U.S. Rates tend to occur from about 1% to 14% in post trab cases. This paper, out of Bascom in ‘97, described the incidence of hypotony maculopathy, which for them was about 1%. Their risk factors, they found, are the classic ones that we’re taught. Mainly younger myopes are higher risk, if this is their first filtration surgery then that’s higher risk as well. Early intervention seemed to lead to good recovery, as this table here suggests. Most patients returning to their preoperative vision.
They also describe a technique that they use during the revision where they put down two sets of flap sutures. So the first set as they normally would is used to just titrate the flow for their IOP goal. But then they use a second set that is extra tight, probably longer as well, in order to increase the IOP in the immediate postoperative period. And then once the hypotony maculopathy is resolved then that second set is cut by laser suture lysis. That way the hypotony is addressed first, while still allowing for normal post trab care afterwards.
The next case that we have is a 78-year-old who has followed with the Duke Eye Center for over 40 years. She had phaco trabs in both eyes, done in 2004. A couple years ago she developed a bleb leak in the left eye that resolved with ointment. But on presentation most recently, she comes back with a recurrent bleb leak from an avascular and cystic bleb. The vision in that eye is 20/50 and the IOP is one. These are her fields. The 10 dash two in the left eye showing more significant field loss. So again, recapping her clinical picture, what kind of options might we have next for her management?
[Leon] Roma, how would you advise this patient?
[Roma] Sorry, I was busy answering a question in the chat. (laughs) For this patient with an IOP of one, now with a recurrent leak. In these cystic blebs, oftentimes you’re going to end up with recurrent leaks because it’s just the pathophysiology of the tissue. So I would probably do an excisional revision depending on what the tissue looked like. If there was conjunctival elasticity, if I have to pull down the conjunctiva that’s pretty much how I would pursue this.
[Leon] Okay, any other thoughts, Joanne?
[Joanne] I think a similar thought process. I guess some more details on whether we think this is still just a very sweaty bleb, if that’s what’s contributing to the IOP of one. Or if it’s some kind of filtration. Given that it’s very cystic, I would be suspicious of it’s just a very aggressively sweaty bleb. So I agree with Roma, I would probably do an excision and pull down. If I thought it really was an overfiltration problem, then I might be leading more towards compression sutures through the conj, through the surgery site to see if we can tighten things up, shut things down that way.
[Leon] Okay, roll the video, James.
[James] In this case again, elected for a bleb shutdown at the same time as an implantation. This is that video.
[Leon] Yeah, so a very ischemic cystic bleb done several years ago, 16 years ago. I didn’t think with pressure’s one, I didn’t think that we would be able to do a real good excision, she didn’t have a lot of mobile conj posteriorly in the superonasal quadrant. So we’re going to open up the bleb and put a patch graft, shut it down. Yes, to Pratap’s point, I probably could maybe I could just place a suture through that flap, but she was leaking. And I felt let’s go ahead and shut the flow completely. I like to use 7-O Vicryl sutures, you could use nylon sutures as well. So once we do this, the thing about this is that you still may have some elevation, may have a little pressure early on, because the ischemic nature of the bleb it could take a week or so for that patch graft to really scar down.
She had fairly mobile conj superotemporally and she’s an elderly, frail lady and I thought a Xen, I used mitomycin with this, a Xen would be a good option. You’re not seeing all the Xen technique for interest of time, but the Xen is a six millimeter stent that’s placed ab interno or ab external. Decided to go ab external with that. And afterwards we got a nice infused bleb, superotemporally. There’s no leak superonasally. And we’ll see how she did.
[James] Post op date one, she was doing better already. 20/50 vision. IOP increased to five and the morphology of the bleb over the Xen was looking good. A nice, low diffuse one. And this kind of persisted in her operative follow ups, and on month three she’s still 20/50, IOP stabilizing to 10 and she is off all of her IOP lowering agents.
[Leon] Harry, there’s some questions from the audience?
[Henry] Yes, some were also answered offline. But here’s an interesting one. There’s one on rotating the suture for these patch grafts to shut down the flow. I guess it’s hard to rotate these sutures. Do you guys have any suggestions or comments on that?
[Leon] Yeah, I’ll ask Pratap. With Vicryl, you don’t really need to, it’s really soft and will dissolve. But you rotate your knots, Pratap? Dr. Challa?
[Pratap] Yes. Yeah, typically I do, same thing.
[Henry] Okay. And then here’s another question. Referring to the last surgery case, why did you decide to leave the ischemic conj behind?
[Leon] This most recent case?
[Leon] Well, I could have done an excision, but I thought in this case the conjunctiva posteriorly, that’s why it’s so important to assess these prior to surgery. That conjunctiva was really scarred posteriorly and I figured if I did an excision that I would not have enough tissue to bring forward. So hence the idea of just covering it up. And over time this will scar down completely. But that’s the main reason I didn’t want to do an excision and pull down on this technique.
[Karim] Just a comment if I may. With some of these bleb revision techniques, I think it’s also good to keep in mind the role of amniotic membrane. And although we have time to discuss it today, there are some good papers where amniotic membrane can be used or conjunctiva can be taken from a different quadrant or the other eye to actually bridge any difficult or tight conjunctiva as a cover. Just something to keep in mind, thanks.
[Roma] Does anyone in the panelists, use the method where I think Dr. Tanaka has videos on this, where the incision is placed behind the ischemic bleb or leaking bleb and he will hook the Tenons posteriorly and then pull that forward underneath the leaking area to the limbus. And then suture that down so that serves as an extra barrier, per se, between the scleral flap and the not so healthy conjunctiva. Has anyone tried that technique?
[Leon] I’ve seen that technique, Roma, but I have not personally tried it.
[Roma] Could be an option for those who don’t who don’t have access to Tutoplast, if they wanted to look that one up.
[Leon] True, all right. Any other questions, Henry?
[Henry] Just one that came up. So after if you do revisions with two sets of flap sutures, for hypotony maculopathy and then, when is a good time to do laser suture lysis if you need to?
[Leon] Anyone want to answer that?
[Pratap] It all depends on the pressure. Typically, the improvement is proportional to the pressure. So as the pressure’s higher, the resolution will be faster of the hypotony maculopathy. So I like to get the pressures up into the high teens, if the nerve can withstand it, even 20 for a little while. For at least a few weeks to even a month or a couple of months. As long as the nerve can handle it. If the nerve can’t handle it then the hypotony maculopathy does get better, it just takes longer because the pressure’s in that 12 to 14 range. I’ve had patients where I had to leave them with pressures of 12 and it took them close to a year for the vision to really improve quite a bit. But it does, it can improve over time. But it all depends on what the nerve can handle. The higher the pressure the better, but if the nerve can’t handle it, obviously, you’re going to have to cut the sutures earlier.
[Leon] This is our last topic.
[Henry] Sorry, just a comment from one of the attendees, Dr. Swali said, Dr. Palmer has previously said three to four weeks when the pressure’s up before you do suture lysis. So thank you for that comment.
[Obi] Our final topic for today is one of the dreaded complications of trabeculectomies and that’s bleb-related infection. This case was actually a case of Dr. Damji’s. It’s an 83-year-old female, presented last month with a 36 hour history of right eye redness, decreased vision, and severe pain and discharge. These pictures are from a different patient, however the patient had a similar appearance on presentation.
Her visual acuity was hand motions. She had an avascular flat bleb that was not leaking. She had severe conjunctival hyperemia and a striking fibrin response in the central AC, as well as the hypopyon. There was no clear view to the fundus but a b-scan was performed and this is the patient’s b-scan here where you can see the tritus present.
This particular patient’s history, she has history of severe steroid response glaucoma. She underwent bilateral sequential trabeculectomy with mitomycin and developed avascular blebs in both eyes. Several months ago, her exam was 20/40, vision of 20/40 in both eyes. IOP 10 in the right eye and 12 in the left. And of note, this particular patient had a recent history of blepharitis. So several weeks prior to this presentation she had blepharitis that was treated by her local optometrist.
This particular patient, her treatment involved immediate pars plana vitrectomy with intravitreal vancomycin, ceftazidime, and TPA. Thought that’d be a good point to stop and allow the panel to discuss how they would have approached this treatment.
[Leon] Yeah, as Obi mentioned these are really tough cases. And have to be acted upon very quickly. We tend to get retina involved very early. There is no good randomized study that guides us to intravitreal injection versus pars plana vitrectomy. But we work with our retina colleagues to jump on this very quickly. Roma, what’s your approach there in California?
[Roma] I think for this particular case, I’m not seeing some description of the anterior chamber or what the vitreous looked like.
[Karim] I have hypopyon. If you go back to the photo, it’s almost exactly what the, lots of fibrin, hypopyon. And then the vitreous was full of debris and so we suspected an endophthalmitis rather than a blebitis.
[Roma] So then absolutely, I would agree, an aggressive approach is warranted. This patient has, basically, a direct conduit from an external infection to the internal aspect of the eye. It’s unlike other, like a corneal ulcer or other types of infections. And it’s unlikely to resolve unless you get the bacteria out. So I agree with the approach of an aggressive maneuver to vitrectomy. I think we may have just waiting one day. And typically at Davis we’ll do the intravitreal injections and topicals and then just see how they’re doing the next day in preparation for surgery. But definitely getting retina involved early.
[Joanne] I also think it’s important just to encourage your retina colleagues to sometimes they make the mistake of extrapolating the EVS findings, which is post cataract endophthalmitis. And to keep in mind these tend to be really virulent organisms and that intervening early and aggressively is probably more warranted. And so I think sometimes retina doctors maybe need a little bit of encouragement to do that.
[Pratap] I completely agree with Joanne. I’ll give you some anecdotal evidence. I’ve had patients that have had endophthalmitis associated with trabeculectomies after they’ve already had vitrectomies in the past. And actually all of those patients, to my reckoning, is only like three patients, but they’ve all done very, very well. The vitreous is just not good in terms of when you have an infection that’s gone into the posterior segment.
Some of these patients if they have a bleb infection, maybe cells in the AC, but no hypopyon, I think topical aggressive therapy is reasonable. Even a Tapon inject is reasonable. But and it’s actually been published, for just straight blebitis with just topical agents. But if they have any posterior segment involvement, I think we really need to push retina to do a vitrectomy in these patients.
[Joanne] I also think the other thing. I really try and encourage my patients to be their own advocates when it comes to these things. Sometimes you look at these patients and you know they have that really thin-walled cystic bleb, they’re at higher risk for developing infection. And so I’ll tell them, “Hey, if you ever get a red eye, and you go to urgent care, don’t let them just tell you you have pink eye. You need to tell them, ‘Hey, I’ve had a glaucoma surgery, I was told I really need to see an ophthalmologist to get this taken care of.’” Because these can really decompensate very quickly. As a fellow, I think it was actually with Dr. Challa, I think one of the patients between the time that the patient called in to the time that they got seen in the clinic, because they lived very far away, the vision had dropped about hand motions by the time they got to see us.
[Leon] Great point, Joanne. We really, if you’re still, the reason we’re doing these sessions is that trabeculectomy surgery is going down. Some good reason in some cases, because of these particular outcomes that can be devastating. But it is important in any trabeculectomy patient that you do surgery on to let them know about things they need to watch out for. And that they should come, I recall having a patient three or four years ago who went to the urgent care over the weekend. And they treated with just topical mild antibiotic and the patient eventually lost his only eye. They need to be instructed, you have to have a nice phone system so they can get into our care quickly. It’s so important to have that patient, to have that education.
How’s your patient doing, Karim?
[Karim] Yeah, so if we could just click there the patient was back a few weeks ago and actually is doing well with improvement from hand motions to 20/400 and continuing to improve. The fibrins all gone. The bleb, luckily wasn’t one of those blebs that was leaking. And it was pretty well shut down just with the intensity of the infection. The patient grew a more excellous BC’s than gram negative. Was quite aggressive. The whole thing had come on within just 24 hours so we felt obliged to do something aggressive here since we thought it was endophthalmitis. So fortunately they’ve done well.
So just a few slides to hit home some of the points we’re making. I think the first thing, when you’re looking at these patients is to distinguish whether the infection is just localized to the bleb, so called blebitis, in which case you see a milky bleb, often some pus around the bleb, hyperemia, et cetera. But often not much in the way of AC reaction. You might get some cells. But the minute you have a hypopyon, endophthalmitis in terms of vitreous involvement, the vision goes down, pain is much more severe. And so vision over the phone is a good screening question. Pain and redness and discharge et cetera won’t help you that much.
And so on the right hand side you can see the hypopyon et cetera, that’s an endophthalmitis. The first two are more blebitis. And the blebitis can be treated with topical intense drops as well as oral, fluoroquinolone typically. And so swabbing the bleb is not helpful, typically, because the culture doesn’t correlate well with the intraocular growth. But if you want to do an AC tap, that can sometimes be helpful. The best bang is to do a vitreous tap and inject and especially if there’s intraocular involvement that’s critical. And whether to do the vitrectomy is up to the discussion with the retina colleagues. So I don’t start steroids typically until after 24-48 hours until the infection’s under control. But then the steroids are quite helpful to decrease the fibrin and sequelae of bad inflammation. The next slide.
Historically, you know it’s scary, but many of these blebs with mitomycin the incidence of bleb leaks and also blebitis and endophthalmitis goes up with time. So you can see at five years, the bleb leak is up to 18%, blebitis at 6%, endophthalmitis around the same as well. These patients need to know that they’re in situation which is precarious for the rest of their life, unfortunately. Next slide.
And so because of that, the risk factors are important to identify. If they’ve had antimetabolite as part of the trabeculectomy, it puts them at more risk. As does the thin, localized blebs, the bleb leaks and full-thickness procedures. We don’t do inferior blebs anymore, I think, because of the risk of endophthalmitis. At one time that was tried. Or if the bleb is interpalpebral and there’s risk of exposure, dryness, and thinning. It’s important to think about often frequent lubrication or just revision to prevent infection in the long-term.
And then some other risk factors on the next slide that are outlined, include if a patient has poor hygiene, with kids, of course, they rub their eyes a lot and are more at risk. Blepharitis, such as this patient had which was untreated. And dacryocystitis sometimes if they get a simple bacterial conjunctivitis it can penetrate quite quickly. And patients with keratoconjunctivitis sicca, et cetera, dry eyes are a sitting duck as well, if they’re not careful. Those that use contact lenses or traumatize the eye. Diabetes is a risk factor too, this patient had hypertension but not diabetes.
And we generally, I think most of us encourage patients who’ve had trabeculectomy not to go swimming in freshwater, or lakes and other scenarios where bugs can get into the eye. And I guess if they want to go in salt water with goggles, they could. But one has to base it on each individual case. I think most of us would recommend against swimming or scuba diving. Next slide.
And so the key thing here, I think this is my last slide now. The question was asked about prophylactic antibiotics. It’s not that helpful. In fact, some studies have shown that it can increase the chance of infection. You get resistance and selection of organisms and resistance to antibiotics. So it’s often not helpful.
And this pneumonic I like a lot: RSVP. When the patient is educated or staff at our office are educated, think about this, the patient should be asked about or remember if they had redness, sensitivity to light, vision decline, and pain. Those are the cardinal symptoms to watch for over the phone when you’re screening. And to treat any external infection or sources, insure good hygiene, lubricate well. And then we talked about this earlier but if blebs are leaking or high risk and very thin, one may want to consider revising those in advance or just watching more carefully for a leak to appear and then advising. I’m glad you saved one of the most devastating complications to the end and it looks like we still have a lot of participants online. Thank you.
[Leon] Thanks, Karim, it’s really important to be proactive. Every time you see the patient in clinic you really want to swab that bleb with fluorescein and really spend some extra time looking for a leak. Because they often time are asymptomatic and they may complain about a little tearing, but you get tearing with the bleb itself. So it’s important to look for leaks very aggressively at each clinic visit.
[Henry] There are a few questions. Couple questions on blepharitis and antibiotic prophylactics which you covered already. So I wanted to direct those questions to this slide. There was another question on steroids. The attendee would notice that the Prednisolone was started fairly early. Would you step up the dosage of the steroids with endophthalmitis?
[Leon] Question for Karim?
[Karim] Just going back to the question. Was the question should we start steroids? Or when should we start it?
[Henry] Stepping up steroids, increasing the dosage?
[Karim] We started it every hour after 24 hours. Because we wanted to give a little time for the antibiotics to set in. And then the steroid’s very helpful for fibrinolysis and preventing sequelae of inflammation. But if you start them too early the worry, of course, is that the infection may take off because you’re inhibiting the immune response to the bacteria. So I think most of us wait a day or so before initiating steroids. But again, the retina colleagues that’s a good discussion, sometimes they prefer to inject dexamethasone straight intravitreal at the time. So I don’t think there’s one answer here.
[Henry] I think the question was would you start the steroid at a lower dosage and then slowly step up?
[Karim] No, I think it’s best to be real aggressive. If you’re going to use it, just use it every hour or half an hour because you need to get rid of that inflammation. In addition to the toxic effect of the bugs, the inflammation is what does these eyes in.
[Leon] So, you guys have hung with us for two hours, talking about trabeculectomy complications. It’s really important that we continue to stress the importance of teaching trabeculotomy and teaching how we manage these various complications that we’ll continue to see. There’s many cases where trabeculectomy is the best option for our patients, despite the age of MIGS.