This is a 12-year-old boy with a history of developmental delay and bilateral posterior polar cataracts. A lensectomy was done with a vitrector and an IOL was implanted in the bag. A Pars plana posterior capsulotomy and an anterior vitrectomy were performed because the patient may not cooperate for YAG capsulotomy at a later stage.
Surgeon: Dr. Asim Ali, University of Toronto, Toronto, Ontario, Canada
This is a 12-year-old boy with a history of developmental delay. He has bilateral posterior polar cataracts. The plan today is to implant a lens in the bag, and I’ll be doing a pars plana capsulotomy and anterior vitrectomy. We don’t expect him to be able to sit for a YAG laser capsulotomy later. So we’ll do all of this in one procedure. I’m going to create a small peritomy me before going into the eye. It is easier and safer to do this step now while the eye is closed, you want to be sure to place your scissor blade behind the conjunctivalo tenons fusion, which is a couple of millimeters behind the Limbus. That way you take off both layers in one block section.
This is a posterior polar cataract, and the patient is at risk for PC rupture. So that’s why we just have to be careful with that. The iris is normal, just widely dilated, you can see that there’s some cortical spokes and there’s a posterior polar cataract there. We don’t have to remove every bleeder, we can just deal with that later, if we need to. We will just proceed with the rest of the case for now.
So it’s important in these cases to keep the infusion anterior. I don’t like to run a posterior infusion unless you’re very comfortable visualizing the entry site, you run the risk of causing retinal complications. If I do this, I always do an anterior an AC maintainer, rather than try to do a pars plana infusion.
I’ve just placed an air bubble into the anterior chamber to keep the trypan blue dye away from corneal endothelium. This boy is mentally impaired and when we assessed him we felt that he would not sit for capsulotomy later. So it is better in my mind to do it now than to wait for later.
We are entering the anterior chamber, just anterior to the termination of the conjunctival blood vessels. As we go in with our cystitome needle, I’ll enter the anterior capsule centrally, the pediatric capsules can be very elastic. And if we have any issues with it going radial, I want to be able to control those. So I’ll typically start centrally and then expand the tear using capsulorhexis forceps. Here I’m grasping the capsular leaflet with the forceps, and I’ll start to initiate our circular capsulorhexis. Again, because of the elasticity of the capsules, you’ll note that the direction of pull is much more towards the center of the lens than it is tangential.
This central polling is to counteract the tendency for the incisions to go radial. Also, you note that I don’t tear too far before re grasping, I try to keep my forceps very close to the point of the tear. And here in this older 12-year-old boy, the capsule appears to be a little less elastic and our capsulotomy is perhaps just slightly on the small side.
We can do a very limited hydrodissection. So, we have to make sure that the wave we put in doesn’t go around, it goes right about till there and stops. So, I don’t go all the way around to the back. You do run the risk of blowing out the posterior capsule, particularly if there are posterior capsule abnormalities as are in many of these cataracts. So, I will stop there, I don’t want to do too much hydrodissection, if I think I can remove the lens easily. I normally like to do a lot more, but we may pull out the posterior capsule if we use a lot of pressure.
Here I’m going to close the corneal incision a bit so that we have less fluid coming out around the smaller vitrector handpiece. You can avoid this by using small incision capsularhexis forceps or doing it entirely with the cystitome needle. But here we’ll just close this down a little bit to prevent excessive leakage, which leads to chamber fluctuation.
The infusion is going in now, the anterior chamber maintainer which matches the size of the vitrectomy handpiece we will be using. It’s easier to put the infusion in if you have it running.
Now I’ve inserted our vitrectomy handpiece and I’m just doing a little bit of aspiration peripherally here to remove some of the cortical material. Sometimes you can remove a lot in the periphery, here I’m going to remove some of the central material first. And I’m using a little bit of cutting here centrally, but you’ll notice I’m only within the opening of the anterior capsule, and I’m constantly keeping the port facing up. So this is one of the few times when we’ll do some cutting with the vitrectomy handpiece on these pediatric cataracts.
Again, as we do this, we’re mostly reaching into the periphery, aspiration only. Try to engage the cortical material, sometimes you have to do a little bit of a cleft creation in order to have enough room to pull the pieces into centrally. Usually once you get the first pie shaped segment out, then you have more room to manipulate and push other sections into.
And again, reaching out towards lens equator, and being sure to reach posterior away from the anterior capsule edge, so that you don’t engage the anterior capsule. Once you get out to the equator, then I simply turn the vacuum on, engage and pull into the middle where I can aspirate at higher pressures. And can even turn the cutter on, if I have a particularly dense section.
I’m trying not to remove the cortical material in the posterior portion of this lens, although that would make it faster. But there may be an opening in the posterior capsule, and it can enlarge very quickly once the fluid starts to circulate. So I usually save that until the end, when I’m pretty happy with most of the removal of the lens material.
Now kind of cleared out that section to the left and above. So now we’re going to work over towards our infusion cannula. And again, it’s still the same technique of reaching out to the periphery, pulling in centrally, using just just enough aspiration to engage that cortical material.
And if you watch the incision, you can see even with that suture in the incision, there’s a fair amount of fluid that’s going out around our vitrector. Sometimes it’s even preferable to completely close the lens implant incision and make a new MVR blade incision to use the retractor through. That way, you don’t get leakage when you’re moving sideways with the vitrector through the incision the set suture in there.
Sub incisional areas are always the most difficult. And sometimes it’s actually preferable to do the sub incisional cortex first. Because as long as you’re working in that area, the remainder of the lens material keeps the posterior capsule back. And so sometimes that’s a way to protect against engaging the posterior capsule. Another alternative way that you can do this is with a bimanual technique, where you have one instrument to the right and one instrument to the left, either with an anterior chamber maintainer like this or with a handheld infusion. And that allows you to switch from one side or the other opposite sides of the eye and get some of that sub incisional material. Looks like I’ve freed up that portion in there. I’m just going to look underneath to make sure there’s nothing in there, it’s going to make things a bit easier. The goal is to try to remove as much as you can before you get all the way to that point. There’s the last little bit here, teasing out this posterior and sub incisional material.
If there is a posterior capsular break, you’ll see a round hole sometimes or even a membrane in the anterior vitreous. In this case the posterior capsule is not broken, which is good. It all looks very clear. If we are going to take out the posterior capsule, there are certainly different ways of doing this. Some people will do it with an anterior approach, the other way able to do it posteriorly or through a pars plana incision. And I’ll just proceed to show you how we do it posteriorly.
To do from the back or parse plana, pars plicata, I think is the easiest way when you’re a beginner with this procedure. Atleast that’s been my experience. If we were going to take out the posterior capsule, and for normally for a 12-year-old boy, I wouldn’t do this. But we are doing this because of his particular situation and mental impairment which precludes sitting at a YAG laser.
Again, there are two basic ways of doing it, you can do it from the front or behind the lens. You can also do it by opening the posterior capsule before or after implanting the lens. And you can do it manually or with the vitrector. So, there are many different possibilities or ways to do this. But what I was saying was I’m going to show you how to do it from posteriorly pars plana approach. Overall, it seems to have the least number of complications if you do it carefully.
People always worry about the risk of retinal detachment. However, in my experience, this is extremely rare complication if you keep your pars plan incision at an appropriate distance. If you try to do it from the front through the corneal incision, that can be very quick, but you run the risk of dislocating the lens or causing vitreous strands to come around the lens and to get incarcerated in the wounds as well as dislocating your lens.
In this situation, we will implant the lens in the capsular bag first, we essentially complete the anterior portion of the procedure and then go from behind the lens and open up the capsule. We’re going to be implanting a one-piece foldable lens in the bag. You don’t want to do wound assist here as much as possible, I really want to place it inside the bag, with these lenses it is really quite easy. And I like these in particular because they open very slowly. You can see how the haptics are traveling slowly. If you do have anterior or posterior capsule irregularities, I feel that gives a margin of safety to allow you to position the lens very gently.
As much as possible, I like to place sutures when there is still viscoelastic in the eye, this allows me to keep my anterior chamber. We’re going to turn on the infusion when we tie the suture. This is to help flush out some of the material and prevent a lot of that from going posteriorly.
So, I often like to do an X or crossbite suture just to make the tension equal on both sides. It’s easier and quicker to close with just one knot. Here the infusion has been turned on now, so a lot of viscoelastic will come out, we don’t have to worry about what’s in the AC. So, we just turned off the infusion just to prevent the eye from becoming too hard. It’s hard to tie and you often end up making the knots too loose when the eye is too firm. So, the advantage in these cases is that you can bury the sutures underneath the conjunctiva there and then we can just turn the infusion on again.
So just finish up our tying, trim lays down.
Good pressure on the eye and our infusion is back on now. The incision is marked about 3.5 millimeters from the limbus for this age patient. We are going in with a 20-gauge MVR blade. We’re going in parallel at right angles to the sclera and you want to raise your hand flat, you want to be able to see the tip there and make sure you’ve got the right spot.
And then we just use the cutter to go in and the first thing we want to do is to open the posterior capsule centrally. So that way fluid can flow from the anterior chamber maintainer and the anterior segment around the lens posteriorly to the vitrector, that way we’re not pulling excessively on the vitreous. Hopefully you can all see the opening there in the posterior capsule. We will make a smaller opening first and then do an anterior vitrectomy.
Vitreous in children doesn’t behave like it does in adults, it’s a lot more solid and viscous. So, you have to move the cutter around a fair amount more to access it. If you only do a limited vitrectomy, then you leave some scaffolding behind for capsular opacity, that the epithelial cells can spread across. So, I’m just slowly enlarging here as we go. We want this posterior capsule opening to be just slightly smaller, perhaps a half millimeter compared to the anterior capsular opening.
Just about there now, just finishing up last little bit of vitrectomy. The vitrectomy is always very difficult to see. Now when you make your posterior opening, you want to be very smooth, and you don’t want to make it too large, because you can push the lens backwards if it’s really large. So we’re just about what we have here is good and then we won’t get posterior opacification. And even if he gets Elschnig’s pearls, they won’t go into the visual axis, they’ll fall off into the vitreous instead, so they won’t cause any harm.
I think both anterior and posterior capsulotomies are pretty well aligned here. So we should be pretty well done. For now, I’m just going to keep it cutting as I come out. This will help prevent vitreous from following the instrument out and getting incarcerated into the wound. Just have to be careful not to cut the posterior capsule as you do that. And I’m just using the cutter at the opening here to clean out any vitreous thats there. We’ll test that wound to make sure that it’s free of vitreous.
And sometimes you can turn your infusion pressure lower here also and that will help keep from prolapsing vitreous out of the wound. Once you’re satisfied, the two are free of vitreous, then closing that with your suture. Some people will preplace the suture. Others will place the suture after the vitrectomy as I’m doing here, and we are using an 8′ 0 vicryl but you can also use an 8′ 0 nylon or 9′ 0 nylon for this wound. And again, you want to try and keep this partial thickness in the sclera.
I keep the infusion running in this situation because I want to make sure that we don’t have a leaky wound. You can use a trocar as well as you make these incisions if you’re comfortable with that. The only thing I would recommend in the child, is that even if you use a trocar, that you go ahead and suture the wounds. The sclera in children is quite elastic and it tends to open up. In general I would always suture these sclerostomies.
Again, that’s all related to the elasticity of the sclera, just like the elasticity of their capsules. Put another suture here through the scleral wound. Looks like it’s leaking just a little bit, so we’ll reinforce it. Here I’ll go back to the 10′ 0 vicyl.
We have to be more careful with these wounds in children in general, it’s easy for them to leak. Sometimes the children will wake up and be rubbing on their eyes, so it’s difficult to control them sometimes. So, you just want to make sure that everything is sealed up as tightly as it can be to prevent any post operative complications.
I’m just going to move this stitch a little further back. Rotate that knot back a bit. And same thing with this one here.
We’ll close the conjunctiva up here with our same suture. This is just for coverage. Although I am taking a little bit of a scleral bite here, try and tack this down a little more solidly, just to help hold it in place. We’ll tie this in place nice and make sure we have that nice and approximated. It’s not irregular, and it’s in the normal place.
I like to make sure that conjunctiva is closed nicely. The assumption is that this child may be at risk for glaucoma, in future of course. So, they may need additional surgery, you just don’t know. So especially if you do glaucoma surgery, you appreciate the conjunctiva that’s been closed and is not scarred up. Glaucoma is certainly a major potential cataract post-surgical complication in children, which was a long-term issue, so you need to be prepared for it even though that he’s an older child, he still has some risk of that. So we’ll just make sure that we have the conjunctiva very nicely closed
And now we’re going to remove the anterior chamber maintainer and you can see how that leaks when it’s pulled out. Again, it’s this elasticity of the corneal incision as well. So sometimes you just need to get that reinflated very quickly, because it tends to shallow and we’re closing the wound again with another 10’0 viral suture. Sometimes I’ll do a temporary stromal hydration to try and keep that incision somewhat closed, and also helps to reform the anterior chamber until you can get your suture in there.
Here, just re pressurizing the eye a little bit, making sure we don’t have any wound leak from either incision. Tie this a little bit more, go ahead and secure our knot. So far, looks pretty good.
I think up here we have just a little bit of a wound leak at our primary lens implant incision. So we’ll go ahead and we’ll put another suture in. And that’s why we always check to see if it’s too loose. But we’ll just reinforce this with one more 10’0. Nice thing about 10’0 nylon or 10′ 0 vicryl if you can access it is that, when it resorbs there’s very little induced astigmatism with it and you don’t have to take children back to the operating theatre to do suture lysis or remove an exposed nylon suture. So, it definitely has some benefits if you can get to it.
So, in summary, we have a 12-year-old boy with posterior polar cataract, we did a lensectomy with an IOL and pars plana posterior capsulotomy and anterior vitrectomy. We’ll just check our wounds again. They look good. All right, that’s it. I think we are done. Let’s do the injections. And I thank everyone for your attention.