Eyeworld

EW GLAUCOMA 62 December 2017 zonular dialysis with a 9-0 Prolene suture double armed with CTC-6L needles. After the zonular dialysis is stabilized, I would reinsert the toric IOL and rotate it to the appropri- ate axis. Then I would remove the capsular retractors. I always wait to remove the capsule retractors until after the IOL is in its final position to decrease stress on the remain- ing zonules. Acetylcholine would be injected to check for vitreous prolapse (peaking of the pupil). If at any point in the case I suspected vitreous prolapse, I would perform a pars plana vitrectomy to minimize vitreous traction. "In summary, with zonular weakness/absence, you must first recognize the zonular problem. The earlier you recognize zonular damage, the less you worsen zonular damage. Second, isolate the anterior segment from the vitreous cavity with a dispersive OVD. The maneu- ver decreases the risk of vitreous prolapse into the anterior chamber. Third, stabilize the zonular weakness with temporary (capsule retractors) or permanent (CTRs) devices. "Let me add a brief word about vitrectomy when vitreous has pro- lapsed through a zonular dialysis. Anterior vitrectomy pulls formed vitreous through the zonular dial- ysis and will commonly make the zonular dialysis worse. In contrast, pars plana vitrectomy pulls vitreous toward the vitreous cavity thereby decreasing the risk of worsening zonular damage." Lastly, Michael Sulewski, MD, Philadelphia, shared his approach to the situation: "There are several is- sues with this patient. I will assume that he is unhappy enough that he wants to have additional surgery to correct his moderate astigmatic and mildly myopic postoperative surprise from what was the intend- ed goal. I will also assume that he doesn't want the –1.50 myopic result even if we were able to rotate the IOL and get it back on the cor- rect axis. The intended postoperative goal was –0.50 so we know that the surgeon missed the mark both with the IOL axis placement as well as the IOL power. "I would offer him the follow- ing procedure as an option. I would reopen the pre-existing temporal incision with a Sinskey hook, inject 1% sodium hyaluronate to deepen the anterior chamber, then care- fully separate the anterior capsule ly likely that the IOL malpositioning will worsen if not corrected early. "My surgical approach would be to first stain the anterior chamber with diluted 1:10 triamcinolone, check for any vitreous, and perform a limited anterior vitrectomy to amputate and remove any vitre- ous coming through the zonular dialysis. A pars plana vitrectomy may alternatively be performed as well. I would then expand the capsular bag with viscoelastic, place several capsular tension hooks to support the area of dehiscence, then place a capsular tension ring. I would bolster this by placing a capsular tension segment in the area of dehiscence with scleral fixation using a Gore-Tex suture. This would have the benefit of providing good long-term capsular support in this patient with presumed pseudoexfoli- ation, especially if we plan to keep a one-piece IOL in the bag. The rhexis opening looks adequate nasally, but may need to be slightly enlarged temporally using a microforceps. Assuming the intraocular lens is intact, I would then rotate the toric IOL into the intended axis of 180 degrees. If I had access to an intra- operative aberrometer, I could also check in real time that the position of the IOL was effectively correcting the astigmatism. Finally, while off label and not indicated at the time of IOL repositioning, a trabecular micro-bypass stent could be placed to augment pressure control in this patient with moderate glaucoma." John Hart, MD, Farmington Hills, Michigan, said, "This is a great case. First, you should warn the patient that he is at high risk for retinal detachment after any intraoc- ular procedure, especially one (like this) that may involve vitreous loss. This is a case that I would perform under a peribulbar block, but since I'd be repositioning a toric IOL, I'd mark the 6 and 12 o'clock position at the corneal limbus at a slit lamp before the block. This is a classic weak/missing zonule problem. The first challenge is to recognize the zonular weakness. The next step is to isolate the anterior segment from the vitreous cavity with a dispersive OVD; I use Viscoat [sodium chon- droitin sulfate/sodium hyaluronate, Alcon, Fort Worth, Texas]. This step decreases the risk of vitreous pro- lapsing into the anterior segment. The next step is stabilizing the area of zonular weakness. The capsular bag would need to be viscodissected open. I would perform this with a dispersive OVD. Then capsular re- tractors would be affixed to the cap- sulorhexis in the area of the zonular weakness. I prefer the double strand- ed capsular retractors from Micro- Surgical Technology [Redmond, Washington] because they have no sharp edges that might damage the capsule. I would viscodissect the IOL out of the capsular bag. I would per- manently fixate the capsular bag to the sclera with a Cionni CTR sutured to the sclera in the center of the Philosopher's continued from page 60 Figure 2. Image of the patient day 1 postoperative at the slit lamp Source (all): Steven Safran, MD

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