This video demonstrates cataract extraction in a 12-year-old girl with bilateral nuclear cataracts. She presented with decreased vision and amblyopia in both eyes. Lens aspiration is performed uneventfully but the IOL is noted to be damaged during implantation. The surgeon demonstrates how to explant the damaged IOL and replace it with a new one.
Surgery Location: on-board the Orbis Flying Eye Hospital in Vietnam
Surgeon: Dr. Asim Ali, University of Toronto, Toronto, Ontario, Canada
Narration: Dr. Daniel Neely, Indiana University, USA
Now the primary surgical wound has been created with the keratome. And you can see this being done clear corneal just anterior to the limbal blood vessels. And then, using a highly cohesive viscoelastic to keep that anterior capsule flat and a bent tip needle cystitome to initiate our capsulorhexis, which will then tear 360 degrees. Now this girl is 12 years old, so it’s not quite as challenging as infant cataract, but it still behaves differently than an adult anterior capsule. And you can see that while to some degree, it’s being led around tangentially, like you do with an adult, you do have to be careful with pulling towards the middle a little bit more than you would normally with an adult. And again, to my point earlier of wanting to stain in the capsule, you can see how that capsulotomy is almost identical to the nuclear opacity size. So the capsular staining is helpful in these cases. Once we’ve got our anterior capsule completed, since there are no posterior capsule abnormalities, in this case, we’re performing some hydrodissection.
Cortex in younger children is extremely adherent to the capsule and it’s always helpful to have that liberated in multiple quadrants, so that you can facilitate the cortical cleanup. Sub incisional cortex is particularly difficult in children given the adherence of the material. Here you can see sutures being placed over the incision because we’re using vitrectomy handpiece, and an infusion cannula in this case. And if you do that through a larger 2.5-millimeter incision, which was utilized for the capsulotomy you’ll have too much leakage around the vitrectomy handpiece, so you’ll want to close that incision down slightly.
Alternatively, if you have access to a small incision capsulorhexis forceps you can do this through simple MVR blade with incision and not have to place the suture and I think that’s ideal, if that instrument is available to you. The vitrectomy handpiece, you see is mostly being used with its port facing upward. The cortical material is relatively dense, so it does tend to follow itself out. And here’s the advantage of having two ports as you can use a kind of a bimanual technique, just simply switching the anterior chamber maintainer and the vitrectomy handpiece to reach that very difficult sub incisional cortex, which is quite easy when you simply go to a port, which is 90 degrees or more opposite of your primary incision. And our last little bit of Cortex has come out there. During the injection of this one piece lens, you can see the plunger is out a little bit further perhaps than normal. And once the lens is in the eye, it’s visible that there’s a crack in the lens implant, off to the right-hand side there. Now fortunately is peripheral, but there are some other cracks extending in towards the middle.
And the decision is made in this particular case to explant the IOL and simply replace it. And I think this is a good illustration of how it’s most easily done, grasping that haptic and cutting directly underneath the haptic that is in your forceps, while it’s outside the wound. These are simple venus scissors and trying to cut across the mid portion of the lens extending from behind one haptic to behind the opposite haptic and that’ll give you two roughly equivalent halves, each with a haptic as a handle to guide them out of the incision. If you don’t cut underneath the haptic you have a hard time removing those fragments. And here you can see that halves are a little bit unequal, so the wounds being enlarged slightly to allow a less traumatic explantation of this larger jagged piece. You don’t want to be dragging this across the endothelium of the cornea. So here you can see that the surgeon is doing a nice job of wheeling that out of there. There’s also a technique of only cutting partially across the IOL and then cartwheeling the two halves out while they remain attached. And you just have to be careful not to contact the endothelium when you do that. Once those two fragments are removed, then you can place more viscoelastic in the eye and go back to a repeat injection. And here you can see that the plunger did not extend onto the surface of the optic like it did with the first implantation.
And now that pristine intraocular lens can be easily dialed into position. I think that’s one of the real benefits of this particular lens, particularly for pediatric cataracts, is that it tends to open quite slowly, and allows you to maneuver into position, particularly if you have an irregular capsulotomy. And here you see this one’s a little on the small side even though it’s perfectly round. But having the slowly opening lens allows you to maneuver into position when the capsulotomy is small, when the capsulotomy is irregular, and there’s a risk of extensions, or even if you have opening in your posterior capsule. So, this particular Alcon lens, I think is really ideal for the circumstances. And at least in the US, this is the lens of choice for pediatric cataract surgery. Once that’s in place, we’ve put a suture across the corneal incision to kind of tighten it up again. And now using the retractor to remove the viscoelastic from the anterior chamber, and now placing some subconjunctival antibiotics and steroids. This step is optional, but maybe preferable if there’s any chance that follow up could be poor, with your patient.
July 18, 2018