Surgery: Trabeculectomy

This video demonstrates a routine trabeculectomy surgery in a 14-year-old young woman with a chronic angle closure glaucoma. A 2.5 mm scleral flap was fashioned in a square shape and a peripheral iridectomy was performed. The scleral flap and the conjunctiva were closed with sutures. The anterior chamber was well formed and the bleb was diffuse at the end of the surgery.

Surgery location: on-board the Orbis Flying Eye Hospital in Yaoundé, Cameroon
Surgeon: Dr. James Brandt, University of California, Davis


DR BRANDT: This is a young woman, who’s about 14 years old, who has very high pressures. Probably on the basis of chronic angle closure glaucoma. And I don’t quite know why she has angle closure glaucoma. But it’s very clear that she needs treatment. Now, she has angle closure glaucoma, so that means I need to pay attention to a few things while doing a trabeculectomy that’s different than a standard trabeculectomy. One of them is I want to make sure that my incision into the eye goes very anterior into the peripheral cornea. If it does not, and I enter the eye prematurely, I can end up behind the iris, which we do not want to do. The other thing I do in all my trabeculectomies is I look at the vascular pattern, and there’s a penetrating vessel right over here. Right over here. And right over here. And I want to avoid creating a flap that involves those areas. Because it’s very hard to control the bleeding underneath the flap. Okay. So I’m gonna start and make an incision, and I tend to make it with a sharp blade. But it’s very important not to push so hard that the sclera is incised. I’ll take this back in a second. But I’ll take the BSS on a 27. I have already previously injected up here some mitomycin. I’m gonna try to get this in here, to blow up the conjunctiva. Sometimes I’ll have to open it with scissors. But I prefer to use the BSS. This is a general anesthetic. Okay. Now I’ll take the BSS. And I’ll then take the Westcott scissor. So I’m trying to get in underneath the Tenon’s capsule here. I’m gonna widen the conjunctival incision here. And I want to be under, right on the sclera here. She has a very adherent sclera. That’s okay. We’ll get the bleeding in a little bit. Go ahead and just dry. What I’m trying to do is create a nice area for fluid to flow. And we’ll cauterize here in a moment. But there’s no point in doing it and then cauterizing over and over again, until we have our dissection done. So we’ll take the cautery now. I want to avoid doing so much cautery that I burn the edge of the tissue. Okay. I’ll take a Colibri and my crescent blade. I’m just using the blade to smooth the surface here. She has a lot of episcleral fibrosis. More than I would expect. Which is more than usual in a child of this age. So I’m going to start creating my flap. I like to make a square flap. I have the blade now down flat. And you’ll see in a moment I’m gonna come right up into the cornea. Like right there, you can see that the blade is up pretty far into the peripheral cornea. And I like this blade a lot. You can use a regular crescent blade. But you can see I’m getting way up into the cornea. So that when I enter the eye, I’m not going to be behind the iris, but in front of it. And I’m just releasing the two wings here. At this point, I’m gonna want a side port, just so that I have access to the anterior chamber. And you can see that she has a little bit of bleeding underneath this flap. That was that penetrating area I was originally gonna try to avoid. I’m gonna take the cautery for a second. Just a little bit of BSS on here. Okay. I think that was all it needed. I always make the SuperSharp towards the temporal side of the eye. So this is the left eye. And the reason I do that is because, if we have to reform the chamber with a viscoelastic, in the clinic it’s much easier to do towards the temporal side than it is nasally, with the patient at the slit lamp. So at this point, I’m able to enter the eye. So this is the Kelly punch that I will use in a moment to create a sclerotomy. And what I want to do is — you’ll notice that I’m aiming with this tip going in the same direction as the cornea. And I will go across. But you can see that I’m above the iris. I’ll take the punch now. I’m turning it vertically. I’m gonna wipe this off there. There’s a little bit of cornea there. Okay. So I’m getting corneal edema, which means that I’m probably splitting the cornea here a little bit. Let me have the SuperSharp back. This edema will go away. That was just me getting in there and dissecting and splitting things. An old style of doing this. I’ll take the Vannas scissor back. Now we’ve made a nice opening. You can see that. Just the 10-0 nylon. It’s non-locking. Okay.

>> Dr. Brandt, can you repeat the type of suture that you’re using?

DR BRANDT: This is 10-0 nylon. So in a patient with angle closure, you want to make sure that you do not have the pressure be too low on the first day, or they will have a very shallow and flat chamber. You’ll notice that I did not trim the first suture, because this is not fully locked. It’s a slipknot. So I can adjust the tension after I reform the chamber. So when cutting a suture under the microscope, to be smooth what you want to do is close — get close to where you’re going, and then close the blade almost to the end, and then when you have it in the right place, you just gently squeeze. If you approach with the blade wide open, then closing it suddenly causes a lot of movement. So the good assistant who reaches over and cuts a stitch approaches, closes the blade almost all the way, and then just gets it into the right place, and it’s just a very gentle movement to close the last little bit. I will take BSS on a 27 or a 30. And I’m gonna reform the chamber, and I’ll dry everything here. I think you can probably see in the 3D video that the eye is — the chamber is shallow. But still formed. And I’m reforming the chamber.

>> There is a question here, doctor. What is the size of the flap?

DR BRANDT: The flap? Do you have a caliper? This is probably 2 to 2.5 millimeters across, I would estimate. Let’s see if I’m right. So I set it to 2.5 millimeters. Yeah, and that’s about right. Now, she’s maintaining her chamber. I’m going to tighten this just a little bit over here. I generally bury each of the knots as I go, rather than do it at the end. Because each knot depends on the other one, in terms of tension. So if I break the stitch, I have to replace it before adjusting the tension for each of these. And you can see I can just touch here, and there’s flow. But she’s maintaining her chamber. So at this point, I let anesthesia know that we’re getting somewhat close to the end. We’re probably about 15 minutes or less from being able to turn the patient over. That’s always important to let anesthesia give a time estimate. Because you don’t want them to, if they have the patient intubated, add more paralytic agent or anything like that. It’s always being a good colleague to let them know what’s happening. And she’s maintaining a chamber. So I’m gonna release this a little bit, so that we can close things. I will take the 8-0 vicryl.

>> How do you decrease the rate of failure from the trabeculectomies?

DR BRANDT: So we applied mitomycin before we came on the screen. And we injected mitomycin subconjunctivally at the beginning of the case. But I also don’t like that oozing there. So before I put the other stitch here, I’m gonna use a little cautery. I’m doing everything I can. These needles are very unforgiving in terms of becoming dull. So this — I’m not gonna do a slipknot, because this is a braided suture that doesn’t slide very well. But I’m hoping to be able to have this buried, so that she is comfortable.

>> There is another question from Cybersight.

DR BRANDT: Okay, hold on.

>> It’s about the distance of the sutures in the flap.

DR BRANDT: I like to make a long pass, in part so that if I need to laser them, I can find them more easily. Did that answer the question that you wanted?

>> Yes, yes.

DR BRANDT: Okay. So now I’m gonna also take some more Tenon’s. Pull it forward. And then go through the conjunctiva. And do the same thing here. And I use a needle driver, just because I can get better leverage on the suture and hold it much tighter. So here I’m gonna see how this pulls down, and this should pull down very nicely. You see how that pulls? I’m just gonna look here and see whether or not I want to do anything further to make sure that this Tenon’s stays behind here. Can I take the… Yeah, the conjunctival forceps. Let’s just see. Because this is nice and tight. But I would like to see this conjunctiva back a little bit further. BSS intraocular, please. We’ll keep things dry here. So she’s not leaking. And she’s developing a nice bleb, posteriorly. But this makes me a little bit nervous. So I’ll show you a little trick that I can do. Which is: I can use — if it doesn’t snap too far — there we go. This type of needle doesn’t go through holes — it cannot create its own hole. But because I’ve already created a hole, I’m not gonna dull the needle too much. So I can still use the hole that I created for the traction suture. And I’ll just create a little knot here. And I’ll sleep a little better tonight, knowing that I’ve pulled everything down tightly, and it’s much less likely for her to have a leak afterwards, by doing this. Okay? I asked you earlier for antibiotics. I also want some atropine drops or ointment, if you have it. And I’ll take the BSS intraocular again, and we’re done. And so here you can see she has a nice bleb. And I’m just gonna re-form the chamber even deeper. And she has a nice, diffuse bleb. And the eye is — I would not say firm, but the pressure is probably 15 to 20, which is where I like it. She had a pressure in the 40s when we started. I would not want her pressure to be 2 or 5 or something like that, because then she’s at risk of developing a flat chamber. And so the person who just reached in and gave her a drop of atropine… And that’s Tobradex? Okay. So this is a general anesthesia case. So you do not want to, at the end of the case, like you do in an awake case, just rip off the drape. Because you can extubate the patient by mistake, if the sticky drape is touching the tube. So I’m being very careful, while anesthesia is holding the tube, to make sure that I don’t do anything stupid. And believe me, I’ve seen it happen. It’s not fun. Anesthesia does not like it when you extubate their patient for them. Okay, very good.

3D Version

Last Updated: October 31, 2022

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