Eyeworld Supplements

BOOST YOUR REFRACTIVE AND CATARACT SURGERY PRACTICE 6 | SUPPLEMENT TO EYEWORLD | DECEMBER 2021 Innovative technologies that enhance my surgical experience Y. Ralph Chu, MD Lisa Nijm, MD, JD Inder Paul Singh, MD Farrell "Toby" Tyson, MD Elizabeth Yeu, MD This article is based off of presentations from an EyeWorld, non-CME symposium —"Enhancing your refractive cataract workflow utilizing innovative technologies from today and beyond"—sponsored by Carl Zeiss Meditec, which took place at the 2021 ASCRS Annual Meeting in Las Vegas, Nevada. The symposium included Y. Ralph Chu, MD, Lisa Nijm, MD, JD, Inder Paul Singh, MD, Farrell "Toby" Tyson, MD, and Elizabeth Yeu, MD. O phthalmology and innovation go hand in hand. The specialty is known for its strong connection to technology and pursuit of ad- vancement in diagnostics, surgical tools, and techniques to enhance the operative experience, improve outcomes, and better patient care. Y. Ralph Chu, MD, described Carl Zeiss Meditec as a company "driving" technological innovation in hardware and software, from the diagnostic and plan- ning stage all the way through intraop- erative tools for advanced outcomes and the postop analysis, tracking performance and opportunities for growth. Precision-driven outcomes with advanced diagnostic and planning tools Achieving the best outcomes postop starts with precise measurements preop. While there have been improve- ments in IOL calculation formulas over the years, there are many estimates in these calculations, said Lisa Nijm, MD, JD. Take posterior corneal astigmatism. The Barrett formula estimates posterior corneal power based on regression for nomogram analysis, she said. Traditional keratometry measures the central 2.5–3.2 mm zone in the central cornea and uses a standard ratio between the anterior and posterior cornea to estimate total corne- al power. Dr. Nijm questioned whether estimating the power of the total cornea and/or power of the posterior cornea vs. just measuring it matters. "You need to look no further than Doug Koch and some other prominent authors," she said of published literature that suggests that the posterior cornea does make a difference. She added later that "accurate measurements of the pos- terior cornea are vital to accuracy of IOL measurements." Dr. Nijm said total keratometry is an accurate and efficient way to precisely measure the power of the cornea. The IOLMaster 700 (Carl Zeiss Meditec) takes telecentric keratometry to measure the anterior and posterior corneal surfaces, offering a total keratometry measure- ment. Dr. Nijm said this measurement is compatible with existing formulas and constants. She added that you can use total keratometry to choose the best toric IOL without needing additional measurements. With the IOLMaster 700, "all the measurements you need are right there, you just have to make sure that you're looking at the output carefully to choose the correct power lens," Dr. Nijm said. Inder Paul Singh, MD, said he has been using a number of lower power toric lenses because of the total keratometry measurements. "It may or may not be a decision of whether I should even do a toric lens; it could be the power of the toric lens. … Even in the worst-case scenario, if I flip an axis about 0.1 or 0.2 from against the rule to with the rule, I'm less stressed about that. It's actually increased my low- er powered toric adoption in some ways," he said. Farrell "Toby" Tyson, MD, said people can get hung up on whether the keratom- etry is the same among different devices. Odds are there are going to be differences because each is measuring at a different central zone, but he said he uses his IOLMaster Ks because they're reproduc- ible. "When I optimize my lenses, I know I'm going to have that consistency," he said. The IOLMaster can also indicate ar- eas of dryness that should be treated lest it affect accuracy of measurements, Dr. Nijm said. Another benefit is the swept- source OCT feature, which Dr. Nijm said can identify problems in the fovea that merit further investigation, which might not have otherwise been apparent. Elizabeth Yeu, MD, spoke on the topic of innovation in surgical planning precision and efficiency. Cataract surgery planning involves about a dozen steps. Most of these steps involve manually inputting and/or transcribing analog data into an EMR instead of digitalizing every- thing, she said. "That's like going to MapQuest and printing out maps. We're nowhere near in ophthalmology and medicine where the rest of society is," she said. "Veracity Surgical [Carl Zeiss Meditec] is one step

• Cover