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ONSITE ASCRS ASOA ANNUAL MEETING 56 | EYEWORLD DAILY NEWS | MAY 6, 2019 by Rich Daly EyeWorld Contributing Writer "Despite the presence of modern technology, post-occlu- sion surge is still a concern," Dr. Khandelwal said. Editors' note: This event was supported by educational grants from Alcon, Bausch + Lomb, and Johnson & Johnson Vision. Dr. Khandelwal noted that shallowing still can occur—and risk the posterior capsule—when vacuum has been reduced. "When you see shallowing of the anterior chamber, it is not al- ways surge," Dr. Khandelwal said. In such cases, examine the irrigation tubing for looseness or leaks. Another cause of shallow- ing unrelated to surge is poste- rior pressure. In response, Dr. Khandelwal urged surgeons to check the lid speculum or ask the anesthesiologist to increase the patient's relaxation. "It allows for less compres- sion when you have that occlu- sion," Dr. Khandelwal said about stiff tubing. "But really it's about the time; you want to have that ex- tra little delay before any shallow- ing of the anterior chamber." Sumit "Sam" Garg, MD, Irvine, California, said the situa- tion is analogous to the difference between using a metal or plastic straw for milkshakes. Metal straws will take more power to suck the ice cream through, but the straw will stay rigid. "But if you have a regular straw, sometimes you get through that thick piece of ice cream and you have just milk down there and you get this big amount of fluid coming through—that's surge," Dr. Garg said. David Chang, MD, Los Al- tos, California, noted that the key to rigidity is its inability to deform. "If you build up vacuum in the tubing, like a suction cup, it gets squeezed, then when it releas- es it gets sucked in," Dr. Chang said. "That's why rigid is better." Additionally, smaller incisions and tighter wounds are key to reduce the threat of surge. "It's about fluid going in and fluid going out, so at that moment of surge the chamber is going to collapse much quicker if you have more fluid coming out of that paracentesis." Some surgeons opt to raise the bottle height or the IOP. "But we're trying to keep these at very moderate IOPs or bottle heights because that way we can have a more beneficial experi- ence for the patient—less corneal edema," Dr. Khandelwal said. Data indicated that newer phaco machines can run higher vacuum without the same threat to the posterior capsule. T he latest phacoemulsi- fication technology has reduced the incidence of surge—but it's still a real threat. "We're so lucky that with the new technology we see much less surge than be- fore," said Sumitra Khandelwal, MD, Houston. "But part of that is still our responsibility to make sure that everything is set up for us to utilize these technologies and make sure we don't have these concerns." Surge, which is the sudden withdrawal of fluid after an occlu- sion break, can result in a quick shallowing or collapsing of the anterior chamber. "Our goal here is for us to recognize that quickly, recognize the moment that you have that occlusion break, and do something to protect the posterior capsule in these cases," Dr. Khandelwal said. To prevent surge, Dr. Khan- delwal said to watch out for cases where the anterior chamber shal- lows every time a lens fragment is caught at the phaco tip. One option in such cases is to decrease the vacuum in the phaco system. "We're able to run these set- tings with higher vacuum but not every case is such that you can do the same settings." Among peristaltic phaco sys- tems, flow rate adjustments help, as do shorter and stiffer tubing. Post-occlusion surge still a concern in new technology Dr. Khandelwal identifies ways for surgeons to avoid post-occlusion surge. The winner of the EyeSeek drawing for a set of Movado Watches was Rebecca Nielson. Enter this code in the EyeSeek game located within the Annual Meeting app for your chance to win one of our four prizes! #123456 723587

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