This video demonstrates a superior oblique tendon tuck surgery in a patient with congenital superior oblique palsy and a severe head tilt.
Surgery Location: on-board the Orbis Flying Eye Hospital, Mandalay, Myanmar
Surgeon: Dr. Monte Del Monte, University of Michigan, USA
In most cases of congenital superior oblique palsy with a large head tilt, we’ll find a tendon that’s relatively lax, a superior oblique tendon. We’re gonna first document that with forced duction testing and maybe exploration, and if we find the typical lax tendon, we’re going to do a superior oblique tuck, which is an uncommon operation. That’s the best one to correct both the head tilt and the vertical deviations in the major gaze positions, because this is a very incomitant type of strabismus. And if for some reason, the superior oblique is not lax, then we have an alternative plan. We’re going to recess the inferior oblique on the ipsilateral side and the inferior rectus on the contralateral side, as an alternative. And now we’re gonna look for a lax tendon. So we’re gonna grab the eye at 3:00 and 9:00. And there’s three steps with this. First we’re gonna retropulse the globe. Then we’re gonna extort the globe. And you can kind of… First you can test for the torsional component, to see how much torsion there is. And that’s about as far as we can go in each direction. I’m gonna put the globe here, and then we’re gonna feel like a flipping sensation. And actually, she’s not terribly lax here. A lot of times, this eye will almost disappear here, before we feel anything. And now we’re starting to get a little bit further back. But you can see the flip back and forth sensation… That tells us that the tendon is there. We’re definitely feeling a tendon. And now we’ll do the same thing on the other eye. So we’re going to retropulse. We’re going to extort. Bury… And we can feel the tendon on this side as well. And maybe it’s a little bit tighter. Hard to say for sure, though. But we’re gonna go ahead and explore the superior oblique tendon, just to see if it is in fact lax, before we make our final decision. So we’re gonna make a superotemporal fornix incision here. About 8 millimeters, 9 millimeters back from the limbus. Not all the way up here. This is the upper lid flipped over. So we want to be in this tissue here that’s a little bit thinner. And we’re gonna make our incision down to bare sclera. And there’s the bare sclera. And we’re gonna spread into the fornix here. To make sure that we’ve got our bare sclera. Small hook. We’re gonna hook the superior rectus. We’re gonna use that as a traction to hold the globe in position. Now we’ve got the superior rectus. We can get the tip of the hook up to the limbus, so we know we have the whole muscle. We’re gonna put a Desmarres retractor in here, to get a look at the superotemporal quadrant. All right. Now we’re gonna look for the superior oblique tendon. Therefore you can see — there’s the superior rectus muscle here, going back. You see the superotemporal vortex vein, right at the tip of my — the big vessel right there, at the tip of the small hook. And then you can start to see that superior oblique tendon, which is these parallel fibers right here. It’s nice and clear there. To isolate the superior oblique tendon, we’re gonna pull the superior rectus nasally. Now you can better see these fibers. And we’re gonna hook it from the front. And now you can see that tendon. You can see the vortex vein nicely here. We have to be careful to avoid that vortex vein. Now we’re gonna try to get very far posterior, so we can try to catch the whole tendon. It can be difficult to see it sometimes. But we’re gonna try to get it all. And lift it up. And there’s the superior oblique tendon. Now you can sort of see it. There’s the vortex vein. There’s the tendon. You can see the fibers in it. We can document we have the tendon by putting our finger in the trochlea and pulling. I pull on this. You can feel it right at the trochlea. And this tendon is getting a little more lax now. You can see it sort of lifting up more. So it is, I think, a reasonably lax tendon. It’s worth trying to tuck. Again, there’s the vortex vein, beautifully displayed there. Try to make sure we’ve got the whole tendon now. It looks like it. You can see it gets wider and kind of fans out when it goes posterior like that. The problem with tendon tucking is that there’s no table to tell you how many millimeters to tuck it. It’s all done by feel and by forced duction test. Until you get the right amount of tension. So that’s what we’re gonna try to do now. So this is a tendon tucker. It goes on the tendon like so. This tendon is actually fairly small. Sometimes they’re much more bulky and big. In congenital superior oblique palsies, often the tendon is fairly atrophic. So now we’ve hooked this tendon. Now we’re gonna crank this sucker down. And what we’re doing is we’re gonna fold that tendon between these two arms. And see how this is folding it in between the arms of this tucking device? And we go down until it’s pretty close to the sclera. About right there. And now we’re gonna put a suture through it, to tuck it or fold it on itself. And this has a scale on it. It tells you millimeters. And we’re at about 6 millimeters now. So we’ve got 6 millimeters each way. So that’s about a 12 millimeter tuck, which is a reasonable sized tuck. I don’t like to tuck the tendon if there’s less than 8 or 10 millimeters of tuckable tendon. There’s a much higher risk of getting a secondary Brown syndrome as a complication from that. We have to make sure that the tendon’s flat, so that both of them are folded on top of each other, as opposed to offset. And that’s what I’m trying to verify here. Try to go in the center of the tendon, and come out on the other side. So now I’m gonna wrap it around the superior pole. I’m gonna go back through it a second time. We’ve tucked the superior fibers. Now we’re gonna tuck the inferior fibers. Now we’re gonna get the other side. Okay. Now we’re gonna do the second pass. It goes in one side, out the other side. This is the second arm of the double armed suture. Now we’re gonna tighten the second one here. We wrap it around the superior pole. We’re gonna go through it once more. Okay. There’s the second. So we’ll do a temporary tie here. So we can test the forced duction and see if this is the right amount of tucking. Now we have to test if that’s the right amount of tuck. Again, I did that by feel. It felt tight. Just above the sclera. And now you can kind of see how that tucked tendon looks. You can see there it is. It’s folded on itself. Now we’re gonna put a suture through the knee, so we can get back through here, if we need to. Which we often do. So now we’ve got this secured. We’ve got the tendon tucked. We think it’s the right amount, but we’re not sure. So now we’re gonna repeat the forced duction test, and we’re gonna see if we’ve got the right amount. With a regular tuck, what we’re typically trying to do is get the eye… When we take the eye inferotemporally, and elevate it into adduction, we want to just feel resistance as the inferior limbus crosses an imaginary line between the canthi. And you can see that now. See? It’s just feeling resistance right about here. See it? I can’t go much further. But just right there. And then you can also do it this way, and go across, and elevate. Again, you want to feel resistance just as it passes the line between here. If you feel it down here, it’s too tight. You’re likely to get a Brown syndrome. If I can get it way up high, it’s too loose. So that’s a reasonable tuck for the type of problem that you had. We’re gonna convert that temporary knot into a permanent knot. The purpose again of this stitch here… Through the loop… Is to be able to get your hook back into this area. It can be very hard to do that otherwise. Now, to convert this, we cut the loop, and one of the two will come out. And now we convert this into a permanent tie. So we’ve got three throws. We’ll put two single throws on top of it. And that makes it permanent. So it’s not gonna slip. Back under the superior rectus. Good. Now we’re gonna secure the end of this tendon flat on top of the original tendon insertion. Right at the anterior edge is the easiest. It’s very low risk. We don’t have to actually suture into the sclera. And it keeps the tendon from flapping forward or backward and changing the force vector of the muscle in the healing process. Most of this tucked area will fuse to the sclera. So we’re gonna find the anterior edge of the insertion, which is right here. You can see it. We’re just gonna lay this tendon neatly on top of that anterior edge. Very careful not to tighten it more. So we just have to lay it down real gently without tightening it any more. And now we just snug it down lightly. And that completes our tuck. Now, that muscle is tightened. Again, 6 times 2. 12 millimeters. Which is a medium sized tuck. Not a bad sized tuck at all. The nice advantage of the fornix incision: It often doesn’t require any sutures to close. So we can just massage the conjunctiva back together underneath the upper lid. And this will heal together nicely. Without any sutures on the outside, it’s quite comfortable for most patients post-op. If you have a congenital palsy with a large head tilt, there’s no substitute for a tuck. That’s really the only operation that works well for that. Again, just getting it right above the line is where we feel it. Just perfect. And it’s good at the end to kind of verify that the eye movements are all okay. That all the tendons and all the tissues have been stretched out. And we’re kind of back to our resting position. About 80%, 85% of the time, this will be the right amount. 10% or so of the time it will be a little too much or a little too little, and we’ll have to touch up the surgery. But it does take a good five or six weeks for enough healing. We’re gonna put a little bupivacaine in the wound here, to cause a little pain relief.
September 27, 2019