Surgery: Cataract/IOL Surgery in a Young Child with PHPV

DR NEELY: We’ve just been doing our prepwork here. We’ve got our traction suture in, and our two pericorneal incisions. See, we’ve got a very interesting congenital cataract. Very pretty. This child is two years old. Little boy. And it’s a unilateral congenital cataract. It involves the posterior portion of the nucleus here, centrally, and then it has these cortical spokes wrapping around the nucleus. Like most congenital unilateral cataracts, this side is a little bit smaller than normal. Axial length is less than the other side. I’m just kind of double checking what the corneal diameter is. The corneal diameter is just under 10 millimeters. So 10 millimeters is — that gets to be about the bottom threshold for lens implant. We’re using a little bit of VisionBlue. There’s some decent red reflex, but I’m just gonna help our visibility by staining that central capsule a little bit better. The lens implant calculation came out to be about a 30/31. So it’s reflective of the small size of this eye. Cut rate is 250 per minute. Maximum aspiration is 250, and the infusion pressure is set at 30 millimeters of mercury. Just little circular motions with low vacuum. When you have a small eye like this, you have to keep in mind what the dimensions are, because you’ll get fooled into making your capsulotomy perhaps smaller than what you need, because the relative proportions are less. It’s probably a little small still here. I’m gonna try and make it just a little bit larger. You notice that frequently I’m changing the focus, and that’s — you know, you don’t have the same type of fluid dynamics that you do with the adult wounds, a lot of times. And so you get more fluctuation of the chamber than what you might otherwise… All right. I think I’m about ready to switch over to aspiration here. The first piece out of the periphery is always kind of the toughest one. We’re seeing that this — the opaque areas of this lens seem to be a little more dense than the non-cataract areas. Now we’re getting some clarity there. Interesting things about pediatric capsules is: Once you get the lens material out of the way, the capsules are so clear that they can be very difficult to see. Especially the posterior capsule. It can be quite interesting sometimes to try and figure out. Cutter’s on here, and I’m using it once in a while. And that plaque that’s back there on the posterior capsule — it’s got kind of a unique look to it. A small eye like this, you have to wonder if this is a PHPV eye, and if we’ll see a talk. I think there’s a real possibility it’s PHPV. I guess we’ll see that. You don’t always have to have a stalk. But the fact that that plaque is on the posterior capsule is pretty suggestive, between the small size of this eye and that, I bet it is a PHPV, and maybe we’ll see a stalk. PHPV is persistent hyperplastic primary vitreous. And when the eye is in its embryonic stages, there’s a blood vessel, the hyaloid artery, that runs right down through the vitreous cavity. It comes from the optic nerve, runs down through the vitreous cavity, and it basically nourishes the lens while it’s forming, and then it disappears. In cases where it doesn’t disappear, you get this stalk running down through the middle of the eye. Just checking to make sure I’m on aspiration, and I am. You’ve got a little bit of corneal edema that’s obscuring the view. So I just want to gently get in there, hook onto something, and tease this stuff out of there. So most of us aren’t real comfortable with our left hand, so I’m trying not to have to do a lot of manipulation here, other than just get hooked onto the stuff and get out of there. There’s a little wedge back there. I’ll try one more time with that. Going back to my 12:00 wound. So there’s that plaque. I’ll see if any of that will aspirate off, or if I’ll wait and get it after the lens. A little bit of it’s come off here, and I think the rest of that is gonna have to wait until after the lens is in. All right. So the capsulotomy is pretty decent. Okay. So I’m just going to enlarge the implant incision. It’s a small eye. It’s gonna be probably a 4 millimeter capsulotomy there, so that lens is gonna have to either be injected all the way in, or dialed in. It’s probably just barely going to fit. So here comes our lens. And I’m making sure it’s going under the anterior lip. It’s flipping a little bit here. The SA lens that we put in — the clear one — so this clear lens comes in powers I think up to 34. You can get some — which is nice for some of these really small pediatric eyes, because that’s a strong powered lens. And they’re so pliable that, unlike some of the early injectable, foldable lenses, these don’t break. These lenses are really flexible. But you really don’t want to stress that capsule edge. Dial that into the bag. Again, that’ll continue to open up a little bit. All right. So, again, this lens optic is about 6 millimeters across. And you can see what a significant percentage of the limbus to limbus distance it’s occupying. Decent-sized lens for a little eye. But it seems to fit just fine. All right. So infusion is on 20. I’ve got the vitrector back. The cutter is off. Aspirating out the viscoelastic here. I’ve got a small tear in the conjunctiva, so I think what I’ll do is, rather than make my incision back here, I’m just gonna take this down across the limbus here. We’ve just got to make sure we get kind of behind the fusion of Tenon’s and conjunctiva here. I’m having to cut this left to right with my left hand, because of where the tear was situated. These PHPV cases, assuming that’s what this is — you have to be a little bit careful about the pars plana incision, because of the fact that the pars plana is abnormal in these cases. It’s generally smaller. May be more anterior in general. So you want to not go quite back as far as what you would otherwise. The downside of that is you might hit the ciliary body and get a bit of bleeding. So we’ll go ahead and change to the posterior settings on the vitrector. We want the 500 cut and the 100 aspiration. And I’ll measure this back. I’ll usually do about 2.5 millimeters, but I’m gonna go anterior here. I’m gonna set this forward, just shy of 2. And I’m gonna go pretty vertical with this, because of this posterior capsule being so funny. Okay. So you see my vitrector behind the capsule here. And I’m going to try and cut a hole next to this early on, so that my aspiration can get to the back of the eye. And then I’ll worry about the plaque. But I need a hole in the capsule so I’ll have flow. So earlier, you were asking whether or not to take this plaque from the pars plana, and I’m not sure that we were answering each other’s question. The plan is to do what we’re doing now, where you’re taking this plaque out after your lens is in the bag and stabilized. You could do a lensectomy through the pars plana, but then putting your lens implant in would be rather complicated. If you were just doing a lensectomy as part of a vitreoretinal procedure, that’s fine. But if you’re doing it as an anterior segment surgeon, there’s probably no advantage to taking that approach. I do think this is a PHPV. I think there is a stalk back there. Right there you can see — at least, we can see that. With the plaque, you know there’s going to be — it just has to be a PHPV. But it’s a mild one, because it doesn’t have distortion of the ciliary processes. So the PHPV eyes can be problematic, not only because they’re small, but because they frequently get glaucoma. A lot of times, you’ll see dragging of the ciliary processes. So that can go on to cause phthisis as well, so a lot of times we’ll take out cataracts, even if we don’t expect visual improvement, trying to preserve the eye and stabilize it. I think this eye probably has some decent visual potential. So we’ve got stable anterior chamber and a small capsulorrhexis. Good lens stability. Therefore no big advantage to having the Miostat in the eye. So not using it. Postoperatively, I’ll keep this child on some atropine. Both of these IOL patients — we’ll keep them on atropine for a few weeks. Because a lot of times children will have these intense inflammatory reactions with the lens implants, and if you’re gonna have synechiae form, you want that pupil to scar up in a large position. If the pupil scars down in a small position, you won’t be able to refract or manage the visual axis in any way.