EyeWorld Asia-Pacific December 2015 Issue

14 December 2015 EWAP FEATURE Most occur during capsulotomy. “Amazingly, almost half progressed to a posterior capsular tear,” Dr. Raviv said. “This was something that once it happened, all of us had our attention alerted.” When and why do tears occur? The type of capsulotomy is one risk factor. “We know that a CCC is the most secure and preventative,” Dr. Raviv said. “[A CCC] prevents the force necessary to have an extension or radialization.” Poor visibility, lens-related factors such as a rapidly progressive intumescent cataract, capsular adhesions, anything that creates difficulty in a CCC, and patient factors all can increase the risk of primary anterior capsular tears. When an anterior capsular tear occurs, “the first thing you want to do is save the rhexis,” Dr. Raviv said. There are, he said, a few different things you can do to prevent radialization: You can continue through the other end, going in the opposite direction; use 25-gauge scissors; convert to a can opener or partial can opener. Dr. Raviv prefers the Brian Little rescue technique, which requires a leap of faith. “Normally, our inclination is to continue in the same manner—sometimes that just progresses and radializes even further,” he said. Adding viscoelastic in the eye to make sure vector forces are confined to the horizontal plane, Dr. Little described a technique of unfolding the flap and pulling in the opposite direction—tearing it like you would an envelope or paper. “I’ve used this technique many, many times,” Dr. Raviv said. “This is something we should all learn and teach the residents.” In one case of a patient with bilateral cataracts, Dr. Raviv created two semicircles, “to have a semblance of a capsulotomy with the effect of two tears.” Dr. Raviv also uses a three-piece lens in these cases. These lenses, he said, provide additional options for implantation—for instance, if the tear does extend, the IOL can be implanted in the sulcus with minimal risk of iris chafing. What of secondary anterior capsular tears? Secondary tears are those that occur after the surgeon has completed the capsulotomy phase. When a secondary tear occurs, as one did for Dr. Raviv in a femtosecond laser-assisted cataract surgery case just a week prior to the APACRS annual meeting, the surgeon should perform anti- trampolining maneuvers: Under OVD, perform I/A, leaving the tear area for last. Before pulling out of the eye, fill the chamber with OVD—it is very important to maintain that capsule in a planar position. In this case, after implanting the toric IOL, Dr. Raviv hydrated the incision before OVD removal— once again to avoid trampolining— and when he performed OVD removal, he did so very carefully. “Here you might not want to be as aggressive in removing OVD,” he said. “Now and again I’m hydrating again, to make sure.” Finally, to ensure a watertight closure and that trampolining never occurs postoperatively, Dr. Raviv used ReSure ocular sealant (Ocular Therapeutix, Inc., Bedford, Ma.). These anti-trampolining maneuvers are the countermeasures that surgeons can take to keep them out of trouble. The femtosecond laser has altered capsulotomies somewhat. In cadaver eyes, while the femtosecond laser was being developed for cataract surgery, laser capsulotomies appeared much stronger. Then, in 2014, Robin G. Abell, MD, and colleagues published a paper that Dr. Raviv said shocked the ophthalmology community. 8 The paper published pictures showing a saw-tooth pattern at the edge of the laser capsulotomy and concluded that integrity seems to be compromised by this pattern. Nonetheless, Dr. Raviv said that newer versions of lasers with updated software have improved laser capsulotomies. “In conclusion, anterior capsular tears are manageable,” Dr. Raviv said. “We have to be vigilant in high-risk situations for them. We should know certain techniques, like the Brian Little technique, or going backwards using 25-gauge scissors…once we do have one, perform the anti-trampolining countermeasures so we can have fewer progressions and normal, perfect results at least refractively. “Femtosecond tears are approaching manual surgery rates and may be preferable in high-risk scenarios.” Dr. Bellucci had an explanation for the “surprise finding” of weaker laser capsulotomies clinically, in live eyes, compared to those in cadaver eyes: “If the eye is moving or trembling a little bit during surgery, during the rhexis, a few shots will be misdirected,” he said. “Probably this can cause weakness. And the point you made about the cadaver eyes are fixed, is probably important. So we should revise our docking procedures for femto.” “It’s interesting that you were saying that initially with the femto cadaver studies, they were showing that it’s a stronger rhexis,” Dr. Chan said. “And with the newer software, personally, I’ve had a couple of times where I see that there is a hinge to the capsule. That is definitely something to check. It’s the moment that you think you’re home-free, you get a little bit lax because things are going so well that things like that happens.” EWAP References 1. Mackool R. Infusion misdirection syndrome. J Cataract Refract Surg. 1994;20:99. 2. Lau OC, Montfort JM, Sim BW, Lim CH, Chen TS, Ruan CW, Agar, A, Francis IC. Acute intraoperative rock-hard eye syndrome and its management. J Cataract Refract Surg . 2014 May;40(5):799-804. 3. Kawasaki S, Suzuki T, Yamaguchi M, Tasaka Y, Shiraishi A, Uno T, Sadamoto M, Minami N, Naganobu K, Ohashi Y. Disruption of the posterior chamber–anterior hyaloid membrane barrier during phacoemulsification and aspiration as revealed by contrast- enhancedmagnetic resonance imaging. Arch Ophthalmol. 2009;127(4): 465-470. 4. Ikeda T, Sato K, Katano T, Hayashi Y. Surgically Induced Detachment of the Anterior Hyaloid Membrane From the Posterior Lens Capsule. Arch Ophthalmol . 1999;117(3):408-409. 5. Sorensen T, Chan CC, Bradley M, Braga-Mele R, Olson RJ. Ultrasound- induced corneal incision contracture survey in the United States and Canada. J Cataract Refract Surg . 2012 Feb;38(2):227-33. 6. Assia EI, Apple DJ, Tsai JC, Morgan RC. Mechanism of Radial Tear Formation and Extension after Anterior Capsulectomy. Ophthalmol . April 1991;98(4):432-437. 7. Marques FF, Marques DM, Osher RH, Osher JM. Fate of anterior capsule tears during cataract surgery. J Cataract Refract Surg. 2006;32: 1638-1642. 8. Abell RG, Davies PE, Phelan D, Goemann K, McPherson ZE, Vote BJ. Anterior capsulotomy integrity after femtosecond laser-assisted cataract surgery. Ophthalmol . 2014 Jan;121(1):17-24. Editors’ note: Dr. Raviv has financial interests with AMO and Bausch + Lomb (Bridgewater, NJ). None of the other doctors declared relevant CSCRS - from page 13