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EW NEWS & OPINION 18 August 2016 by Liz Hillman EyeWorld Staff Writer YES Connect Optics, Abbott Park, Illinois]. This maintains cutting efficiency, while reducing the repelling action of pure longitudinal phaco that tends to kick microscopic nuclear fragments toward the corneal endothelium." How does one know wheth- er settings are right for quadrant removal? Dr. Cohen said the most im- portant factor for distal followability is aspiration flow rate, or you can be in foot position 2 and bring the phaco needle closer to the fragment to have the same effect without increasing flow rate. Once the frag- ment is in the center, it is held in place for phaco by vacuum. During irrigation and aspiration (I/A), Dr. Chang said one can use linear control of vacuum in foot po- sition 2, with a very high maximum setting due to the small aspiration port. "With linear vacuum, the more I push my pedal down in position 2, the higher the vacuum limit is," he said. "For cortical cleanup, you typ- ically need three different levels. I first access low vacuum (e.g., 50 mm Hg) to attract material to the tip. Then I need a 150–200 mm Hg level to grab and grip the cortex without evacuating it. This level allows me to strip and peel the cortex away from the capsule. Once the cortex is free and safely held mid-pupil, I maxi- mize vacuum by flooring the pedal and fully evacuate it. Having linear control of vacuum for I/A essentially pert panel first reviewed the basics of why and how to choose settings for aspiration flow, vacuum, and power modulation. Webinar highlights Dr. Chang first explained that aspira- tion flow rate determines the speed at which things happen. Therefore, when facing a tough case, trying a new machine, or transitioning to a new phaco technique such as chopping, surgeons should slow the procedure down by lowering the as- piration flow rate. Vacuum, he said, determines the grip and holding power. "If a quadrant keeps falling off the phaco tip because you don't have a strong enough grip prior to a chop, you might consider increasing the vacuum," Dr. Chang said. "What limits how high we can set the vacuum is, of course, post-occlusion surge. Chamber shallowing occurs when too much fluid surges into the phaco tip as soon as occlusion breaks from a high vacuum level. We know that the cornea can collapse from excessive surge, but consider that the posterior capsule can flex forward with relatively minor levels of surge." Dr. Chang said that the most important advances during the past decade have been with phaco power modulation. "Non-longi- tudinal phaco replaces pure axial motion of the phaco tip with either torsional movement—Ozil [Alcon, Fort Worth, Texas]—or elliptical movement—Ellips [Abbott Medical Personalizing phaco settings for optimum safety and efficiency T hose unfamiliar with flu- idics in the eye might not risk changing settings on their phacoemulsification machine and could thus be missing out on significant safety and efficiency opportunities, said Berdine Burger, MD, Carolina Eyecare Physicians, Charleston, South Carolina. "The phaco machine is too often treated like an unknown black box," said Dr. Burger, the facilitator of the recent ASCRS webinar "Phaco Fun, Do You Know Your Machine?" sponsored by the Young Eye Surgeons (YES) Clinical Committee. Edwin Chen, MD, Ocean Eye, San Diego, said one of the main reasons the YES Clinical Committee decided to develop and host the Phaco Fundamentals webinar series is to help young eye surgeons learn to transition from generic resident settings to more refined personal settings. "In talking to young surgeons, we found that many of them were not comfortable with the mechanics behind fluidics and how this related to their experience in the OR," Dr. Chen said. "The basis of settings modification is a deep understand- ing of how each parameter affects movement in the anterior cham- ber and how those parameters are interrelated. From there, I think it is a matter of slowly adjusting things and refining those adjustments as you see how your modifications affect fluidics in the [anterior cham- ber.]" With Dr. Chen as the moderator, the panel was composed of David F. Chang, MD, clinical professor, Uni- versity of California, San Francisco, and Kenneth Cohen, MD, Sterling A. Barrett Distinguished Professor of Ophthalmology, University of North Carolina School of Medicine, Chapel Hill, North Carolina. The webinar delved into how surgeons can best set their phaco machine parameters and how to modify those settings for more complicated situations or when complications arise. The ex- Phaco fundamentals: How and when to adjust your settings A re you able to confidently adjust your phaco machine settings to produce a desired result? Could you recreate your settings from scratch if they were not available on your machine? How did you arrive at your current settings? In this month's column, we recap some of the highlights from the recent ASCRS webinar "Phaco Fun, Do You Know Your Machine?" The full webinar can be viewed at www.ascrs.org/node/23004. We have asked webinar presenters Berdine Burger, MD, Edwin Chen, MD, David Chang, MD, and Kenneth Cohen, MD, to recap the webinar's most salient points and offer some additional pearls. YES Committee member Sumit "Sam" Garg, MD, also provides insights for getting to know your available phaco platforms. In addition to the resources available through ASCRS, I recommend that surgeons still in training programs take advantage of the ready accessibility of faculty mentors and familiarize themselves with how they came to develop their phaco settings. For surgeons already in practice, take a moment to reflect upon your current settings and determine if there are any settings in need of adjustment or updating, and call upon available resources for additional guidance whenever necessary. Most of all, do not be afraid to get to know your phaco machine. This webinar is the first in a series discussing phaco fluidics, with subsequent sessions slated to delve into more specific surgical circumstances and the potential intraoperative adjustments that might be considered. Be on the lookout for informa- tion regarding future webinars, and check the ASCRS website for any webinars that you may have missed. Charles Weber, MD, YES Connect co-editor continued on page 20 " Be willing to play with your settings. Small, intentional adjustments of a single variable can make a significant difference in efficiency and safety. " –Berdine Burger, MD

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