EyeWorld Asia-Pacific December 2015 Issue

12 December 2015 EWAP FEATURE financial interests. three, sometimes you need four, sometimes you need five, and particularly if the iris is a bit delicate, you might not want to dilate it as much as a ring might do, you may want to be able to customize your dilation.” He used a needle rather than forceps to create a rhexis. There were some missing zonules; Dr. Barrett compensated by using additional hooks to support the capsular bag in that region. He used a vertical chop for the very dense cataract; viscoelastic to restore the integrity of the bag before removing the last nuclear fragment, which is when the bag tends to collapse when dialysis is unsupported. Dr. Barrett said that the viscoelastic provides wonderful surgical support to maintain the bag in those circumstances. Once again, Dr. Barrett preferred an occluder over a suture to deal with the irregular pupil. “I have a strong aversion to suturing the iris to deal with dilated pupils, eccentric pupils,” Dr. Barrett said. “I find the occluders less traumatic. When you suture an iris to close a defect you often drag the pupil away from the center and beyond. I like the Morchers best of all—they’re not the right color—but they work well because they give you support as well in the capsular bag because the zonules are often deficient in those circumstances.” He also did not feel the need to suture a Cionni ring—the additional support of the sector iris prosthesis was sufficient. However, implanting the lens in such a case does need additional support—otherwise, the pupil will remain updrawn. “You can use either scissors to do a little sphincterotomy…or you could use a vitrector to enlarge the pupil,” Dr. Barrett said. Postop, though the patient still had some edema—which Dr. Barrett hoped would clear with time—the patient gained 6/24 vision in the eye previously thought unsalvageable. “The devices we have—iris diaphragms, iris hooks, scissors when we need them—can help deal with these complex cases,” Dr. Barrett said. “They keep us just outside the point of no return, just outside the event horizon so we can deal with complex cataract surgery and eccentric pupils.” On the point of sutures, “I think it’s a small defect, I’ve had good success with suturing, because you just need one with the Siepser knot or McCannel suture of your choice,” Dr. Chan said. “You’re not dragging it that significantly. If it’s probably more than 3 clock hours, I’d say that you’re getting into a risk of dragging and making the pupil more eccentric than it is.” “I disagree when you’re losing iris and you try and close an iris defect where you’ve lost some tissue which is often the case, you suture it and you see your sutures almost tear,” Dr. Barrett said. “If you haven’t lost iris and the sphincter’s being divided for instance, or like a dialysis where you haven’t lost tissue, then I agree with you. I stand to be corrected. But I often see cerclage being done, these sutures really bringing the pupil down, and I say, my gosh, that looks traumatic.” Posterior capsule rupture Dr. Bellucci had the “huge task” of speaking on ruptured posterior capsule. He began with predisposing factors. Some of these factors, he said, can be addressed preoperatively— eye characteristics and conditions such as axial length, anterior chamber depth, pseudoexfoliation, miosis, and asteroid hyalosis. Patient conditions, surgeon conditions, and operating room conditions are important as predisposing factors as well. Some of these factors are intraoperative—such as poor visibility and incorrect maneuvers. Dr. Bellucci said that surgeons should be cautious during the terminal stage of phaco or I/A, saying this was the most dangerous period of surgery, when post- occlusion surge or excessive ultrasound power could lead to posterior capsule rupture. When capsule rupture does occur, signs include eye changes such as sudden miosis or mydriasis; the behavior of the cataract such as difficulty to rotate and, more obviously, falling away of the nucleus; and direct observation— actually seeing the rupture as it develops. “However, as the suspicion arises, we must modify the surgical plan,” Dr. Bellucci said. “This is an important point: We should modify the surgical plan when we get the suspicion, not when we get the evidence of a posterior capsule rupture.” Ruptures happen most commonly during capsulotomy or hydrodissection. Anterior capsule tear may also be a risk. Posterior polar cataracts and capsular block syndrome are a danger during hydrodissection or during nucleus rotation. They may also happen during intraocular lens insertion. In terms of developing a surgical plan, the goal is to finish the surgery while minimizing surgery duration and damage to ocular structures. Dr. Bellucci said that planning must rely on a list of decision-making factors: timing, when in the procedure; location, where in the posterior capsule; size, small, medium or large; shape, round or irregular, extending; whether patient is cooperative or anxious; whether the surgeon is an expert or in training. “I have a few personal general guidelines,” Dr. Bellucci said. “I think we share most of those: Using an adhesive viscoelastic that can use vitreous or lens particles in place while we work; we lower the bottle, we lower the aspiration, we lower the vacuum to reduce turbulence within the anterior chamber. I frequently prefer going on for a few steps with manual surgery using small bores that allow mass suction avoiding vitreous. We can use triamcinolone to evidentiate the vitreous and we can always use vitrectomy, that’s always needed to get rid of the vitreous.” The surgeon should avoid allowing lens material to mix with vitreous because that leads to severe inflammation in the postoperative period. “If left within the anterior chamber, inflammation and endothelial loss will be the case; in the posterior chamber, it will eventually transfer to the anterior chamber,” Dr. Bellucci said. “In the vitreous chamber, it will lead to significant inflammation and even glaucoma.” Meanwhile, traction on the vitreous may lead to cystoid macular edema or even retinal CSCRS - from page 11