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EW CATARACT 24 by Ellen Stodola EyeWorld Staff Writer In order to enhance efficien- cy during phaco, he said that the tip head was sandblasted, and to improve safety, the tip edge was rounded. "Even if the posterior capsule was aspirated by accident, it wouldn't be ruptured even at vacu- um more than 500 mm Hg, as long as the ultrasound was not emitted," Dr. Akahoshi said. For more than 2 decades, he has been using the phaco prechop technique, chopping the nucleus into pieces under the viscoelastic material and using a phaco prechop- per prior to the phacoemulsification. Currently, Dr. Akahoshi said that prechop can be attained with a fem- tosecond laser, but he still prefers a manual prechop in all of his cases, which amount to around 9,700 a year. "For the phacoemulsification of the prechopped nuclear fragments, I always use the phaco tip with its bevel down so that the ultrasound energy is effectively used to emulsi- fy the nucleus," he said. "If I use a Kelman tip with its bevel down, it is difficult to make complete occlusion of the tip toward the nucleus, and there will be so much stress on the incision." Over the years, Dr. Akahoshi has experimented with different tip designs. He developed a 1.1 mm round flare tip, which was sold as the Akahoshi Tip from Alcon. However, he could not get it to work with the OZil handpiece because it was bent 20 degrees. This led him to develop 12-degree tips, as well as off-centered tips that were bent 12 degrees, with the bent off-centered tips working more efficiently than the straight ones. He said his initial square off-centered tip had a 1.2 x 1.2 mm big tip head, but a desire for a smaller head led him to continue improving the design. Harmonyx tip The Harmonyx tips (ASICO, West- mont, Ill.) are a 1.1 x 1.1 mm square tip and an oval off-centered tip, Dr. Akahoshi said. These tips come in straight, Kelman style, and re- verse Kelman (Akahoshi) style. For surgeons who use the divide and conquer technique or a chopping technique, a straight or Kelman Physician has been experimenting with off-centered and other variations in phaco tip designs V arying phaco tip designs can aid surgeons when dealing with different types of cases. The design may also be a matter of preference for the surgeon. Depend- ing on the surgeon and preferred phaco technique, a specific tip may be desired. Takayuki Akahoshi, MD, Tokyo, discussed several phaco tips he has designed over the years and why there was a need for differ- ent bent, off-centered, straight, and square tips. Evolution of phaco tip design "Initially the off-centered tip was designed for the Alcon OZil torsional U/S handpiece [Alcon, Fort Worth, Texas]," Dr. Akahoshi said. The oscillatory movement created by the OZil handpiece requires a bent phaco tip because there is no cutting effect with the conventional round, straight phaco tips. On the other hand, most of the surgeons in the world preferred a straight tip rather than a bent one, he said, and the only effective phaco tip available for the OZil was the Kelman style round tip. It was at this time that Dr. Akahoshi decided to find another tip design. By plac- ing the tip shaft off-center to the aspiration port, his first off-centered tip was made with a round flare tip design, he said. "It looked like a straight tip and effectively worked by the torsional phaco mode." However, he took note that the lateral part of the phaco tip played an important role in cutting the nucleus. "To make the length of the cutting edge longer, the round tip was modified to oval," Dr. Akahoshi said. "To enhance the cutting effi- ciency maximally a square tip was designed." The tips were clinically tested, with cumulative dissipated energy (CDE), aspiration time, balanced salt solution consumption, and corneal endothelial cell loss data collected. "From these clinical data, the square tip was found to be the most effi- cient and safest." April 2015 Off-centered phaco tip design According to Dr. Akahoshi, the Harmonyx tip provides for a safer and more efficient procedure. For surgeons who use a divide and conquer or chopping technique, he recommends a straight or Kelman style tip, and for those who use phaco prechop or femtosecond surgery, a straight or Akahoshi tip may be best. Source: Takayuki Akahoshi, MD continued on page 27 Two views of the Harmonyx phaco tip. These tips come in 3 different styles: straight, Kelman, and Akahoshi.

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