In this lecture, Dr. Brandt explained in detail about the surgical options in children with glaucoma. The lecture covers Goniotomy, Trabeculotomy and Trab 360 surgical techniques which are demonstrated by videos. Dr. Brandt also discussed the present and future trends in glaucoma surgery.
Lecturer: Dr. James Brandt, University of California, Davis
Dr. Brandt: So we treat glaucoma in children with surgery. This is not a disease that can be treated with eye drops, because it’s asking a great deal of a mother or father to be putting drops in three or four times a day every day of the child’s life. And if these organizations are done early, the operations can sometimes, if not sure the disease, control it for many, many years.
In addition, putting babies on medicines can cause many side effects. So prior to around 1940 or 1950, as I said yesterday, glaucoma blinded every child. And it was this doctor in San Francisco who developed a technique that he called goniotomy. He developed this technique for both adults and children. And in the early 1940s, he realized that although the operation did not work very well in adults, it worked very, very well in children.
Goniotomy, as I demonstrated to you earlier, requires a good view of the anterior chamber angle. In the 1960s, two doctors, one in the United States and one in the United Kingdom each developed a technique we now called trabeculotomy. This operation accomplishes the same thing as a goniotomy. And I will show you in the diagrams how that works. The advantage of trabeculotomy is that you do not need a clear cornea. So this is what a goniotomy is. And we use a contact lens similar to what I showed you at the beginning to visualize the anterior chamber angle.
We fill the anterior chamber with viscoelastic. And then we use a needle, or a little knife, to open up the anterior chamber angle. And from a single incision, we can usually open up the angle for about 120 degrees. Here are some photographs of an old style of trabeculotomy. This is the original Hoskins-Barkan lens. Now I days we use a different lens called a Swan Jacob lens. And nowadays we even have the disposal lenses like you saw.
So here is a video of a goniotomy. I usually dilate my — the children to take photographs of their optic nerve and make other measurements. And then I put Miochol into the eye to construct the pupil. And then put in viscoelastic. This is a Swan-Jacob lens.
And then I go in with a special needle, but you don’t need to use that. You can use just a 25-gauge needle. This is a very inexpensive, very cheap surgery. And here you can see the surgeon’s view. And I’m going to adjust the focus here. And I’m adjusting the focus because it’s very high magnify caution and you have to get it just right and now I am taking the knife and going across to open up the angle.
And so you understand the principle of this. Once it is done we remove the viscoelastic. And I use a vicryl stitch so that we don’t have to remove the stitch later in a baby. Here is the appearance of the anterior chamber angle after the operation. Over here is the untreated angle. And here is the angle that has had the goniotomy.
As I said before, you need to have a clear cornea with good visualization of the angle structures in order to do these types of surgery. And as I said before, two different doctors developed the operation we call trabeculotomy. The original technique involved creating, as you can see on the right side of the screen, a scleral flap. And then we cut down into the canal of Schlemm and we put a suture to confirm that we are in the right place, and the suture travels down the canal of Schlemm. This is a photograph I took about 27 years ago of a baby, and you can see the dark line from here to there. And that is the nylon suture inside the canal of Schlemm. And Dr. Kimu here with me knows this is 27 or 28 years ago, because last week we saw this young woman. She’s now an adult, and she’s just got married. And as I discussed yesterday, we can now do genetic testing. So I had a long conversation with her last week about meeting with a geneticist to figure out exactly what mutation she has so she can be counseled about whether her children will have this same problem.
Once the metal trabeculotomy is inside the eye, we rotate it to break into the canal. So this is called a trabeculotomy ab externo, which means trabeculotomy from the outside. The goniotomy is called goniotomy ab interno, which means we’re cutting the angle from the inside out.
In the 1970s — 1990s, some colleagues of mine in Atlanta, in the United States, developed a very nice technique of using two sutures, 180 degrees apart, to open the angle all the way around. And here is an example of this. And is you can see that I’ve created a small incision and have opened up the canal of Schlemm. And this is a 6-0 nylon suture. You can see the cornea is much too cloudy for us to do anything else.
I keep tapping the suture to make sure that it has not gone into the anterior chamber by mistake. Now I’ve made an incision on the other side. Once I know that I’m in the right place, I’ve changed it from nylon to polypropylene, blue. And we’re feeding it back in the opposite direction. Because you cannot see the suture, there’s always the possibility that the suture is going where you do not want it to go. So it is always reassuring to go to the other side and you can see the suture has followed the canal all the way around.
So now we have sutures in both directions. So now we have a suture that goes this way and that way. And now I will pull and, bang. You can see that the suture went all the way around. So I do not do that technique anymore, but it is also a technique that is very inexpensive because you’re just using sutures.
But here I’m creating that same dissection to get to the anterior chamber, or to the canal of Schlemm. And I’m using a special catheter that has a little light of, a fiberoptic, that has a blinking light. It is also a catheter, so I can inject viscoelastic if I’m getting stuck. And I can push it around and you can see the light go all the way around. And you can even use a prism if off good view. You can see that the blinking light is in the proper place.
Here you can see the blinking light coming around as push. The advantage of treating 360 degrees is you know you have treated the complete angle. Here you can see I’m going to pull. And now I have opened up the angle 360 degrees. And we want to see blood in the eye, because it means we have reached the venous system. And in that video I said at the end the next die that hyphema, that blood, was gone. And that tells us that we achieved what we wanted to do and opened up a drain for the eye. All of these surgeries, like any kind of surgery, can have complications.
You can use the needle or the knife in the wrong place and cut the wrong structures. If you use the knife in the wrong way or have it in the wrong position, you can damage the lens and cause a cataract. And you can have hyphemas that sometimes last for several days. Trabeculotomy can have other complications including tearing the base of the iris, stripping Descemet’s membrane, and creating a trabeculectomy instead of opening up want angle you can have too much fluid coming through. The two operations achieve the same end goal. And Dr. Douglas Anderson in the 1980s did a prospective study where he took babies who had glaucoma in both eyes and he flipped a coin and did a trabeculotomy in one eye and a goniotomy in the other eye. And what we found was the two procedures were equivalent in terms of success.
If a baby had a goniotomy that failed, usually the trabeculotomy in the other eye also failed. So when both eyes worked, there was no difference between the two eyes. So let me tell you a little bit about where things are moving over the next few years. None of these operations work forever. Sometimes they do, but that’s the exception, not the rule. And we now know that damage to the conjunctiva predisposes failure of things like trabeculectomy and failure of things like glaucoma drainage devices.
And as glaucoma surgeons, we like to think like people who play chess. We always want to be thinking a few steps ahead. So we prefer, now, to do as much of our surgery through the cornea without disrupting the conjunctiva. We are moving towards, for children, and even for some types of glaucoma in adults, we want to spare cutting on the conjunctiva. Benefits of doing the angle surgery in children is that we target the tissue where the disease resides. And all of these techniques of going through the cornea from the inside out bears touching the conjunctiva, as I said. But the downsides of doing the surgery from the inside are that they are very technically challenging it and requires that the defect only be in the trabecular mesh work and nowhere else. And that is not always the case.
So one of the techniques we are doing in children, but also adults with certain forms of glaucoma is a procedure we call GATT. Which stands for goniotomy-assisted transluminal trabeculotomy. And this is a procedure that was first described in 2014 and appears or very good in children, patients with juvenile open-angle glaucoma, and patients with things like pigment dispersion syndrome, exfoliation, and steroid glaucoma.
So here is what the procedure is, and I’ll show you a video in a moment. But what we do is we put that same catheter into the anterior chamber and feed it all the way around, but on the inside, not on the outside. So here you can see a video of a GATT procedure that I did in an adult.
So here I have a beautiful view of this young adult angle. I’m using a small blade to open up the canal. And you can see I’m making a small incision and I’m going to peel it down. See how I can peel it down and open up the angle. You didn’t — I guess the video messed up. But you can see that I’m inserting the catheter into the canal.
This video’s a little longer than it needs to be. So I apologize. You can start to see the light coming around here. We’ll make it go faster here. So now I’ve grabbed it from the inside. And now we pull and the whole angle is opened up.
And that is the whole operation. And here you can see, when I put the goniolens on, you can see that I’ve opened up the angle all the way around. And the nice thing here is I have not touched the conjunctiva. And we leave some healon in the eye. And this is what she looked like the first day. But within a few days, the blood was gone and her pressure was much, much lower.
The people who developed this technique also do this in children. And here you can see diagrams from their article. So here is an 8-month-old that I did with a GATT procedure. So you understand the principles of the procedure.
So it’s a little bit harder to do in babies. Yeah. So here you can see putting the device into the canal. And I’ll move it along in the interest of time here. I need to edit these videos to make them shorter. Here I’m reaching across to get the device. And I’m just flushing out the healon. And you can also get a sense that when I raise the pressure, these blood vessels became clear. Which tells me that we’ve connected the inside of the eye to the natural drain of the eye. And these are the sutures of vicryl that I put in place before we softened the eye.
And this, in the photograph here, shows you what the angle looks like after we’re done. And here is an ultrasound that shows the open angle. So there are some alternatives to this. I believe that this will, in the United States, is becoming the standard. It’s now still very expensive because that catheter that has the fiberoptic is much too expensive. But some people are doing this just with a suture. I have not been able to get a suture to go all the way around, but I still try every time. And the beauty of that approach, here, would be that it would cost you only the cost of a suture, some healon, and a gonial lens.
This is another device that we use that was developed in the United States. And this is another way to do this from the inside out. And this was one that I did a year or two ago on the flying eye hospital in Vietnam. So you’ll see this. I would predict that this would become — all of these devices will become less and less expensive over the next few years.
But just like the previous example, we constricted the pupil. I put healon in the eye. And then this is the special device that goes in. And if you remember the diagram of the device, it has a little dial on the — for the thumb. And now that I engage the canal of Sclemm, I just rotate that dial. And it pushes a suture into the angle. And you see how it now has gone into the canal of Sclemm.
And I’ve advanced it all the way and it goes out 180 degrees. When I’m happy that it has gone to the right place, I lift up off the gonioprism, as you’ll see. But I’m going to start tearing the canal. You see how that opens up? Okay?
And then I just retrieve the tube. Or, rather, the suture. You dial it back. And then we go in the opposite direction. And here you can see where we have opened up the angle. And we inject the suture in the opposite direction.
So through a single incision, we have opened up the angle 360 degrees. Just like many devices in the United States, they’re much too expensive. That little device is like, $600 or a thousand dollars. But I am sure that people are going to develop much less expensive ways to do it. And with skill, you can do much of these things just with a suture and a lens. So that is how I manage childhood glaucoma in the United States with angle surgery. But here in Cameroon, it would not be difficult for you to do a goniotomy in a selected patient because all you need is the lens. And I will leave you a few of those disposal lenses.
And so when you encounter a child with a reasonably clear cornea, you could use the prism, fill the anterior chamber with viscoelastic and use a 25-gauge needle. All it costs is the cost of the viscoelastic and a few stitches and a disposal needle. So I hope you understand from the videos how you would be able to do that. So I think that’s the end of my talk at this point. I’m happy to answer questions.