EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
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E W FEATURE 116 by Erin L. Boyle EyeWorld Senior Staff Writer Femtosecond laser-assisted cataract surgery complications Most complications occur in the preop and intraop stages of the laser- assisted procedure O ne of the advantages of the femtosecond laser- assisted cataract surgery procedure is that it has a safety profile similar to manual cataract surgery, but when prepping for the procedure and during it, physicians should be aware of issues that can arise. "At the beginning of the femto- laser cataract surgeries, the most fre- quent complications were docking problems due to loose conjunctiva and conjunctival redness due to higher suction force. Partial capsulo- tomy and more central corneal wound location occurred more than expected," said Zoltan Z. Nagy, MD, professor of ophthalmology, Semmelweis University, Budapest, Hungary. Dr. Nagy, the first clinician to use the laser for cataract surgery, said that most of the issues have been or are being resolved with improvements in technology. He uses the LenSx laser (Alcon, Fort Worth, Texas). "With the invention of the SoftFit patient interface [PI] with the LenSx, most of the problems have been solved because the pressure went down, there was no corneal folds, capsulotomy became free- floating in 97% [of cases], and the surgical field increased by 12.5%. As the corneal wound reached the lim- bal area, surgically induced astigma- tism became much smaller," he said. R obert J. Cionni, MD, medical director, The Eye Institute of Utah, and adjunct clinical professor, John A. Moran Eye Center, University of Utah, Salt Lake City, also uses the LenSx machine. "Fortunately, complications have been very few since the intro- duction of the LenSx SoftFit PI," he s aid. "[There are] only what I would call 'mild annoyances.' Capsulo- tomies are now much more pristine and in nearly 100% of cases, complete or free-floating." "The only other common complication, or better stated 'side effect,' is mild subconjunctival hemorrhage that dissipates fairly q uickly after the procedure," Dr. Cionni said. William W. Culbertson, MD, professor of ophthalmology, director of the cornea and refractive surgery services, and the Lou Higgins Chair of Ophthalmology, Bascom Palmer Eye Institute, Miami, uses the Catalys laser (OptiMedica/Abbott Medical Optics, Santa Ana, Calif.). "I encountered complications in our clinical trial when we were using a curved interface, especially with the capsulotomy, and incomplete cutting, but the companies have improved the machines and made it so that it's much more predictable," he said. He said the complications pro- file for femtosecond laser-assisted cataract surgery is running the usual course of the "natural history of a new device," with physicians learn- ing how to use the machines for the best possible outcomes over time. "I was around for early phaco back in the mid-70s, and there were a ton of potential complications with that; as people used it and the machines improved, it's changed the landscape of cataract surgery over the last 30 years," Dr. Culbertson said. "I think it will be the same with this." Preop Non-clinically, Dr. Culbertson cited the expense of femtosecond lasers for cataract surgery as a major preoperative complication. "That's the biggest complication because it's complicated for your wallet. The second biggest complica- tion is that it takes extra time. The medical complications are small," he said. Clinically, the preop docking procedure can pose a challenge, Dr. Culbertson said. He said the prob- lems begin when the eye is tilted. When attaching the eye to the laser, if the eye is off center, this can increase the chance of suction loss, resulting in incompletion of treat- ment. If the centering is 10 degrees off, the eye will not be properly centered for functional access to the laser, he said. Manual adjustments can assist, but do not always work in these instances. The best way to avoid this complication is to stop the laser and recenter the eye within the first few seconds of docking, he said. The laser should be coupled "concentri- cally to the limbus." The LenSx SoftFit PI helps with tilted and decentered docks, render- ing them an uncommon occurrence, Dr. Cionni said. Docking with the device is easy and quick, he said. "Occasionally, however, we will encounter a patient who is not as cooperative as desired [and] the docking is not perfectly centered or a small degree of tilt is found. Suc- tion loss is extremely rare and in- deed, a complication I haven't seen in my last 1,000 cases," Dr. Cionni said. "You will occasionally find a pa- tient with such a large corneal diam- eter that the primary or secondary incision would end up more anterior than desired if made at the most peripheral extent available with the femtosecond laser," he said. "In those instances, I have disabled the primary and/or secondary incision and instead constructed those inci- sions manually." In addition, the pupil must be dilated for proper capsulotomy seg- mentation, Dr. Culbertson said. De- veloping a protocol for the nurse to sign off that he or she administered dilating drops in time for correct di- lation is important, he said. Patients who receive drops in adequate time but still do not have good pupil dila- tion might not be good candidates for laser treatment. Intraop A key intraoperative complication in femtosecond laser-assisted cataract surgery is incomplete anterior capsu- lotomy. Dr. Nagy said that he and his colleagues found that this was the most important complication in the use of the femtosecond laser for cataract surgery. "I suggested to follow the con- tour of the rhexis with the capsulo- tomy forceps meticulously to avoid anterior tears. It was a successful approach," he said. Dr. Culbertson said patients moving during the capsulotomy could cause this complication. Time is vital. The Catalys machine makes the capsulotomy in 1.5 seconds. "You want to make sure the eye is stable in the capsulotomy, no matter the time it takes. Believe it or not, some people can't keep their February 2011 Femtosecond phaco techniques March 2014 AT A GLANCE • New and improved technology continues to reduce femtosecond laser-assisted cataract surgery c omplications. • Complications occur mainly preop and intraop. • Take care when docking a patient's eyes before the procedure, stopping to redock if the eye is not centered. • Watch for incomplete anterior capsulotomies. A 100% complete capsulotomy made with the LenSx laser and SoftFit PI Source: Robert J. Cionni, MD 108-125 Feature_EW March 2014-DL2_Layout 1 3/6/14 3:59 PM Page 116