EyeWorld India December 2020 Issue

FEATURE 16 EWAP DECEMBER 2020 R enowned cataract surgeon Chee Soon Phaik, MD, presented five cases illustrating what she considers the simplest ways general cataract surgeons can fix a subluxated IOL. Case 1: Subluxation into anterior chamber For her first case, she began with a pars plana vitrectomy with triamcinolone staining at 50% dilution, grasping the IOL so it would not drop during the procedure. She manipulated the single-piece PMMA IOL into the sulcus, but had to fixate it to the iris to provide support as the zonules were partially dehisced— she did not want to open up a large incision and could not cut the IOL. She supported the optic with a Sinskey hook, bringing it forward, and injected miochol to provide optic capture. Still supporting the optic, she passed cutting needles with prolene 10-0 through the iris behind each of the haptics. Once done, she popped the haptics back through the pupil to avoid bunching up the iris and causing ovalization of the pupil. She used a Siepser sliding knot to secure the iris and IOL haptic, but did not tighten the initial three throws until the IOL was centered. She finalized the knot with one reverse and one forward throw. She said that a McCannel suture could also be used. With paracentesis just next to where the fixation point is, one can retrieve the sutures and tie the surgical knot. Dr. Chee said that it is very important to perform peripheral iridectomy at the end of the procedure to prevent a reverse pupil block. For this procedure, Dr. Chee used grasping forceps, intraocular scissors, a suture- retrieving hook or Kuglen hook, and 10-0 prolene suture. Case 2: Subluxated Anterior Chamber (AC) IOL with haptic migrating through large peripheral iridectomy For this case, Dr. Chee planned to explant the AC IOL and exchange it with an Artisan lens (Ophtec) since the incision had to be enlarged to 6 mm. After explanting through a superior limbal incision, she made sure no vitreous was left in the anterior chamber by injecting triamcinolone 50%. She performed a bimanual 23-G vitrectomy through snug limbal incisions. With the Artisan lens flipped over—concave surface forward—she rotated it horizontally. She grasped the Artisan lens with implantation forceps, pushed it through the pupil into the retropupillary space. Holding onto the IOL and bringing it forward, she pushed some iris through the claw haptics to enclavate using her viscoelastic cannula. She repeated the step on the other side. The procedure is “really very, very quick,” she said, “suitable for elderly patients who cannot tolerate much manipulation.” For this case, she used Artisan implantation forceps (Ophtec) and a cyclodialysis spatula/ viscoelastic cannula. Case 3: Subluxated IOL with Capsular Tension Ring (CTR) in bag In this case with 50% intact zonules, the IOL with a CTR had begun to subluxate. She planned to fixate the IOL using a Canabrava technique using 6-0 prolene. She prepared a 27-G needle by bending it, then filled the anterior chamber with dispersive viscoelastic. Confirming that there was no vitreous in the anterior chamber, she came through intact conjunctiva and full thickness sclera 2 mm posterior to the limbus with the tip of the needle bevel up, just behind the haptic of the IOL-CTR capsular bag complex. She threaded the 6-0 prolene suture through to the needle tip from an opposite paracentesis, flanged the retrieved tip of the suture to prevent it slipping out. She repeated these steps at the 1.75- mm mark just ahead of the initial needle point, going behind the iris but above the IOL-CTR bag complex, looping the other end of the suture back in to meet the needle bevel and then pulling it out with the needle to tighten. She repeated the procedure at the diametrically opposite site to create another belt loop. She used the unflanged ends of the sutures to titrate the tension on either side and center the IOL- CTR bag complex. She cut the suture leaving 2 – 3 mm to the The Simplest Way to Fix a Subluxated IOL for the General Cataract Surgeon From the lecture by Chee Soon Phaik, MD, Singapore Professor National University of Singapore (NUS) & Duke-NUS Medical School Senior Consultant Singapore National Eye Centre