This patient presented with a history of blunt trauma, a dilated atonic pupil (6-7mm) and a cataract.
A multifocal toric IOL was implanted and pupillary cerclage was done to bring the pupil size to 3mm in size.
Surgeon: Dr. Ike K. Ahmed, University of Toronto, Canada
>> This patient has had a history of blunt trauma, with resultant cataract and dilated atonic pupil that was measured to be between 6 and 7 millimeters preoperatively. She was also very motivated to try to be spectacle-free, postoperatively, and was keen on the multifocal lens, which we’ll discuss shortly. Our goal here was first to remove the cataract, examining for any potential zonular weakness with a history of trauma, and her zonules appear to be fairly stable, after the capsulorrhexis was performed uneventfully. Phacoemulsification and IA of cortex is performed uneventfully, and we’ll proceed in this case to place a capsular tension ring here, just for security purposes, and to ensure adequate centration, especially since we’re considering the use of a multifocal lens. She also had around 2 diopters of with-the-rule cylinder. As you can see, we’ve marked the cornea on the steep axis of the intended placement of this multifocal toric lens. As you see here, with this pupil-independent single piece acrylic multifocal lens, in this case, this lens has 2.25 diopters of cylinder correction on the IOL, along with this multifocal design. The IOL is positioned into the correct alignment. I rotate it into the position here, to sit parallel to those marks. And the viscoelastic is removed from behind the lens, to ensure and prevent postoperative rotation. At this point, we’re going to ensure the IOL is centered well, after we reject some Miochol, in this case, and also some viscoelastic, to stabilize the anterior chamber for the pupil repair component of the procedure. We’ll position the lens here using the first Purkinje images we see here, to center it over the bull’s eye of the multifocal lens, as you see, and of course, in this eye, we have it placed slightly nasal, to sit in position with the patient’s visual axis. We will then examine the iris. As you can see here, the iris is still intact. Fairly spongy. And of course, can be stretched into position here. And we’ll start in a nasal paracentesis with a 10-0 prolene suture on a long CIF-4 needle. This is the pupillary cerclage technique that we’re gonna use. The use of a micrograsper, you see in this case, in our left hand, helps us to mobilize our iris into position, into the needle. So the needle actually doesn’t do a lot of the work. Actually, it’s the forceps hand, bringing the iris to the needle, that helps pass the needle through the peripheral iris. We then will place a needle through an adjacent paracentesis, with the use of a docking needle, to prevent any entrapment of corneal fibers. Notice that the bites are made approximately half a millimeter from the pupil edge, and approximately a millimeter apart or so. This will help to help round out the pupil as much as possible. And again, you can see how we switched hands here in this case. Our left hand is holding the needle, while the right hand is holding the micrograsper. The needle is docked to a 27-gauge cannula. And then is removed through a paracentesis. Notice how we place these paracenteses here one third of the way around the limbus, to allow the needle to be passed along one third of the iris. We will then pass both needle ends again back into the eye, through their respective paracentesis, back through into the main incision. And this allows us basically to have the sutures out for the main incision. As you see, we’ve come nasally, all the way around temporally, using a double armed — as we’ve said — 10-0 prolene suture. We’ll then tie the suture with a pair of microtiers. The microtier here is being used to essentially pass the suture not into the eye. This is a modified McCannel. As you see here, we’re basically drawing the knot into the eye here, to create a pupil size of adequate size and shape. Our goal here is basically to match this patient’s fellow eye, which is approximately just between 3 to 3.5 millimeters. This is the usual size. We will then basically lock the knot with a back-handed throw here. And again, rather than the knot coming — or the suture coming out to the incision, we’re passing the knot into the eye here, with the aid of a micrograsper. This is certainly a helpful technique as an alternative to the Siepser sliding knot or the complete intraocular tying. And we feel this is a very straightforward technique to use. We will then basically spread the iris around the pupil margin to avoid any bunching up of the iris in one particular spot. And here we see the multifocal lens well centered, with a well centered pupillary cerclage that has closed the iris now to adequate size.
December 26, 2019