Eyeworld

EW FEATURE 112 New technology in cataract surgery • April 2016 AT A GLANCE • A technology like aberrometry is important because the state of the eye is constantly changing as it is manipulated and operated on. Having the most up-to-date measurements will enable the surgeon to get closest to the desired outcome. • When entering information into an aberrometry system, be accurate and aware of the possibility for human error. • Inputting data into these systems can help surgeons to improve nomograms and formulas for the future when treating patients. by Ellen Stodola EyeWorld Senior Staff Writer The tool can be used intraoperatively as well as postoperatively to help surgeons track outcomes T he ability to obtain accurate measurements preopera- tively is key in a surgeon's treatment plan for a pa- tient. However, being able to measure and adapt intraopera- tively, based on any changes the eye may undergo during different parts of the surgery, is also important. The ability to make these adjustments can lead to better postop results for the patient. Darcy Wolsey, MD, the Eye Institute of Utah, Salt Lake City, Robert Weinstock, MD, the Eye Institute of West Florida, Largo, Florida, and Susan MacDonald, MD, Lahey Clinic, Peabody, Mas- sachusetts, discussed the value of intraoperative aberrometry. There are a number of systems available that surgeons use to help during the case as well as to track and improve outcomes following surgery. Some of the surgeons noted that they use the ORA system (Alcon, Fort Worth, Texas). Using intraoperative aberrometry "I think the challenge of astigma- tism right now is that even though we have good ways of measuring it preoperatively, there are aspects of astigmatism that we still don't fully understand," Dr. Wolsey said. Using aberrometry to improve outcomes VERION overlay to identify primary and secondary incisions VERION overlay showing axis for toric intraocular lens Source: Darcy Wolsey, MD One of those aspects is the effect of posterior corneal astigmatism. Additionally, differences among devices pose a problem. Sometimes surgeons get overloaded with infor- mation, she said. The surgeon may end up with different values using readings from auto K, topographer K, IOLMaster K (Carl Zeiss Meditec, Jena, Germany), custom refraction, or the LENSTAR (Haag-Streit, Koniz, Switzerland). "Sometimes you get lucky and they're all the same," Dr. Wolsey said, but sometimes there's a distinct difference among values or enough of a difference that it would affect what power toric the surgeon will use. Dr. Wolsey thinks that ORA helps manage all of the information the surgeon has. "I think it can help guide the variables among those measurements we have preoperative- ly," she added. When the ORA technology and the concept of measuring the eye intraoperatively was first devel- oped, it was groundbreaking, Dr. Weinstock said, because no one had taken measurements during surgery to guide decision making. "The first thing surgeons have to understand is it's a new paradigm—the concept of taking measurements while you operate," he said. In the operating room, the surgeon does things to the eye that can change its shape, like making the wound, making the paracente- sis, and taking out the cataract. By taking measurements after those, the concept of getting more accurate biometry makes a lot of sense, Dr. Weinstock said. "When we measure the eye after we've made the wound and taken out the cataract, we have a new state of the eye, which is different than it was during preoperative testing," Dr. Weinstock said. Now it's possible to make decisions for IOL power selection, astigmatism management, and correction. For astigmatism correction, surgeons can use intraoperative ab- errometry to determine what power toric to use, and once the lens is in, it helps to determine where it can be left. For smaller amounts of astig- matism, aberrometry readings can be used to decide whether or not to open incisions or do a manual incision. Preoperative measurements are good and can get you in the ball- park, but surgeons are always trying to improve results, Dr. Weinstock said. Intraoperative aberrometry doesn't replace any of these tools, but it's another data point while in the operating room. Dr. MacDonald said it's incred- ibly important that both the OR team and the surgeon are familiar

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