In this video, Dr. Neely demonstrates a series of pediatric cataract surgeries.
- The first one is a 3-year-old child with a completely opaque lens. The capsule was stained, vitrectomy and bimanual techniques were used to aspirate the lens.
- The second patient is a 6-year-old child with traumatic cataract which has become completely white. The lens was aspirated and IOL was implanted.
- The third patient is a pseudophakic with trauma. The lens implant is in place but there has been an extensive proliferation of lens material and contraction of capsular edges that are interfering with the visual axis.
Surgery Location: on-board the Orbis Flying Eye Hospital, Addis Ababa, Ethiopia
Surgeon: Dr. Daniel Neely, Indiana University School of Medicine, Indianapolis, USA
DR NEELY: I’m going to share with you a series of several pediatric cataracts. This first one is a three-year-old with a completely opaque lens. So I’ll be using a vitrectomy technique and a bimanual technique. I’m also staining the anterior capsule here with some vision blue. I generally will use a vitrector to perform anterior capsulotomies in children under five years of age. And I like this bimanual technique. As you can see, I’m holding a vitrector in my right hand, and I’m using an infusion handpiece in my left hand. These two incisions are placed approximately at the 2:00 and 10:00 positions. Using a cut rate of about 1,250, and a maximum vacuum of about 3 millimeters of mercury, but I’m just kind of using the minimum amount of vacuum it takes to engage that anterior capsule, pull it into the cutter, and enlarge the capsulotomy. The goal here is to get a circular, relatively smooth capsulotomy that is about 5 to 5.5 millimeters in diameter. Even with the vision blue dye, you can see the visualization is difficult. So we’re working around the edges, making sure that we don’t have any tags of capsule present before we move on to just using aspiration to evacuate the cortical and nuclear lens material. Once satisfied with that, then we’re using mostly the port-up aspiration handpiece. So I’ve taken the vitrector out, now that the capsule is open. And I’m inserting this aspiration handpiece, and the thing I like about this is that — while you can aspirate the lens with a vitrector, this has the benefit of this flat diamond dust-coated end that really helps you to strip the cortical material off the lens capsule, and polish the capsule, so that you’re not leaving behind much lens material that then forms posterior capsule opacification or Soemmering’s rings. So I think cleaning this out as well as possible is very important, and therefore I like this particular handpiece. The beauty of the bimanual technique, while it may be a little more difficult to learn, the beauty of it is that you never get stuck with subincisional cortex, because you can simply switch hands, as I’ve done here, moved my aspiration handpiece to the other port, and now I can reach underneath where I had lens material remaining, and quite easily aspirate that out of there without endangering the posterior capsule. Rather than using phaco power, if I encounter any thickness to the nuclear or cortical lens material, I’ll just simply rub the two handpieces together, and it kind of feeds it into that little hole, the aspiration port, so that you can take thicker lens material out. Usually not much of that is required. I would then place our viscoelastic. I like to use a highly cohesive viscoelastic in children. I’m going to use the same clear corneal incision that I was using for the vitrector, so we’re carefully enlarging it here with the lens implant knife, to allow our intraocular lens injector. My preference is for the monoblock one-piece lenses, such as the Alcon SN and SA60 lenses. I like them because they open very slowly. So when you have a vitrectorrhexis or compromised anterior or posterior capsule, you can easily maneuver these lenses all folded up into those openings without stressing the capsular edges. They are also very flexible lenses, so they’ll fit even small eyes. Now, once we have that lens in place, I’m going to close down the lens implant incision to a smaller size, because I’m going to use a pars plana technique here to open the posterior capsule. Because of course this will get opacified. It’ll be just as bad as a cataract. Now, in this aged patient, I’ll want to be going in through pars plana about 2.5, 3 millimeters posteriorly. So I’ve gone back slightly further, to open my conjunctiva, and now I’ll remeasure before I go in with the MVR blade through that same sclerostomy. And once I can see my vitrectomy handpiece back there posteriorly, I still have the irrigation in the front of the eye. First thing I want to do is to open up that posterior capsule, so that we have ease of flow of fluid from the anterior to posterior chambers. And then I’ll enlarge that posterior capsulotomy until it’s about 4.5, 5 millimeters in size. I’ll perform a little bit of vitrectomy then, before I withdraw the instrument. Now, the beauty of the pars plana technique here is that when you withdraw the instrument, you’re not going to pull any vitreous around the lens. If it goes anywhere, it goes through that sclerotomy that we just closed. We still have our viscoelastic in the anterior chamber, so now I’ve gone back with the vitrectomy handpiece, anteriorly, to remove that remaining viscoelastic. And we’ll also do any repositioning of our lens that we may need to do, because you do get a lot of fluctuations in the anterior chamber. This second patient is also a young child, about 6 years of age, who has a traumatic cataract. And it’s become completely white. Centrally, the lens looks to be in pretty good shape, despite the opacification. However, down at the 5:00 position, superotemporal on the screen right now, it’s noted that there’s a little more scarring and involvement down there. But this doesn’t preclude us from doing a normal anterior capsulotomy style here with a bent needle cystotome and Utrata forceps to tear our capsulotomy here centrally, away from those areas of scarring. Because it is a younger child, and because the lens is intumescent, of course we’re wanting to go very slowly, and not liberate a bunch of milky material. Not get radial tears. So there’s frequent regrasping, frequent reapplication of viscoelastic. Use a high viscosity viscoelastic. And the direction of pull here, you can see, is consistently back towards the middle of the eye, almost like a rhexis rescue maneuver. Now, this lens has liquefied. It should come out pretty easy. So we’re using a standard I/A handpiece here. And you can see the kind of sheets of liquefied cortex coming out. Even the nucleus is largely liquefied in this particular case. Now, as we get this lens material out, you can see that again the 5:00 position, superotemporally, that there’s some significant opacification of the capsule itself. Where perhaps it’s been ruptured. There’s also dense scar tissue of the posterior central capsule. So this stuff is not coming off easily. And it’s expected to be quite fibrous and dense. So what I’ll be doing here is placing the lens, and rather than doing a pars plana approach, I’m going to continue after this from the front side. So I’ll get my lens in position here, dial it into position, and then close down that implant incision slightly. But by going from the front with MVR blades and scissors and the vitrector, I should be able to better engage that scar tissue than I think I could from going in with a posterior approach. Now, I’ll need to push the lens out of the way here slightly, as you see me doing. So you’ll need a decent sized anterior capsulotomy, and then using vitrectomy-type settings, I’ll open this posterior capsule centrally, so a cut rate of around 1,250 or more, maximum vacuum of around 300, and infusion pressures around 30 millimeters of mercury. And open the central 4 millimeters, 5 millimeters of visual axis here. We don’t need to worry about this peripheral scar tissue and opacification. But we do need a visual axis that is functional from a vision standpoint, and that we can postoperatively do examinations through of the posterior segment, as well as perform retinoscopy, which in these younger children is going to be critical in our postoperative management. And again, subconjunctival antibiotics and steroids in this case. Now, this next case is a pseudophakic, actually, but again, from trauma. This patient has a lens implant in place. But there’s been extensive proliferation of lens material and contraction of capsular edges that’s really interfering with the visual axis here. Decided to start off with the posterior segment component first. So here I’m measuring back about 3 millimeters again. I’ve opened up the conjunctiva with a limbal peritomy. Here I’m using a trocar. We’re using slightly smaller vitrectomy handpiece than normal. I usually will use a 20 or 23. But you can use a 25, if you like. Sometimes the trocars don’t go through very well. I went ahead and switched over to just using a sclerotomy with the MVR blade, which is why the incision is slightly funny in shape, after using the trocar. But once I cleared up that central portion, the vitreous — closing this up with some 9-0 nylon, and we’ll make a clear corneal incision next and address some of these retained lens materials and anterior capsule edges. So clear cornea with an MVR blade. And I’ll use the same MVR blade here to kind of stab into that retained lens material. I want to open up where the capsular bag is fused, so that we can get a raw edge to work with, with the vitrector. And also we’ll be wanting to insert the vitrector in aspiration mode inside that retained lens material, to debulk all of that, so that we can deepen our anterior chamber, as well as clear the visual axis. You’ll see these Soemmering’s rings get quite thick in a lot of these kids, and therefore we need to remove enough lens material to let that deepen up. Here we’re working anteriorly. The cut rate is going to be 1,250 down to 250, depending on how dense the material is. And then the aspiration is — the vacuum is kind of limited to about 300. I decided to go back to the posterior segment here, to open up a bit more of that visual axis and access some of that lens material, which wasn’t coming very easily. But here now we have a reasonable visual axis open. So we’ll close this sclerostomy back down again with some 9-0 nylon. These children’s eyes — they tend to be very elastic. And I will close all of the incisions normally, whether it’s a sclerostomy or clear corneal incision, unless it’s very small, because there’s just such a risk of postoperative wound leaks with these kids. Especially when they do things like rubbing their eyes. 10-0 vicryl is being used on the cornea here, which is really a great suture.
April 16, 2019
2 thoughts on “Surgery: Pediatric Cataract Surgeries”
Hello , pls let me know what cut rate , vacuum do you use for anterior vitrectomy in pediatric cataract surgery , I use anterior approach.
Thank you .
Dr . Fatma .
If using a posterior segment vitrectomy such as the Alcon Constellation or Acurus, with a 20 or 23g handpiece, I set the initial cut rate high, around 2500 and have it decrease to 100 when the pedal is fully depressed. This gives a high cut rate for normal vitreous and capsule work with slower cutting to engage dense or scarred capsule or lens nucleus as needed. Inversely, I start with a low vacuum 0 that increases to 300 as the foot pedal is depressed. This allows you to precisely trim a capsulotomy and place the minimum amount of pulling on the vitreous unless you need it. When using anterior segment machines for vitrectomy, it is a bit more complicated and less effective… if not been very happy with them in my limited experience but when I have used anterior segment machines such as the Alcon Laureate, I used a cut rate of 250-1000 (slower for lens, faster for vitreous) with an aspiration flow of 5-10 and vacuum of 100-250 (lower for vitreous and higher for lens). I would be very interested to hear the comments of others who mainly use anterior segment machines… any advice out there?