EyeWorld Asia-Pacific September 2012 Issue

35 EWAP rEfrActivE September 2012 The SMI Surgery Guidance system Source: SensoMotoric Instruments The Callisto Eye computer screen is pictured behind Oliver Findl, MD. The surgeon sees the overlay in the system’s eyepiece. Source: Oliver Findl, MD learning curve, said Dr. Zaldivar, but it is possible for a surgical team to become too comfortable and dependent on the tool. Even so, “it’s a system that eliminates big amounts of error that most [surgeons] produce even if they don’t know they produce it,” he said. SMi Surgery Guidance The SMI Surgery Guidance is a three-part system compromised of the Reference Unit, Surgery Pilot, and Microscope Integrated Display. The system supports precise positioning of the incision, limbal relaxing incisions, centering and sizing of the capsulorhexis, centering of multifocal IOls, and the exact orientation of toric IOLs. The Reference Unit determines the K-values, limbus, and pupil location of the patients’ eye and simultaneously captures a high- resolution reference image of the eye, pupil center, eye structure, and vessel structure. The Surgery Pilot is a touch-screen computer connected to the microscope camera where the measurements and images taken with the Reference Unit are displayed. “The measurement data is stored on a USB stick so the transfer of the data from the Reference Unit to the Surgery Pilot is easy,” said Chen Weng , clinical marketing manager, SensoMotoric Instruments. Before surgery begins, the surgeon chooses the target axis, incision, lens locations, and rhexis location and diameter. After this planning stage is complete, the Microscope Integrated Display provides a tracking overlay. “The system is totally contact and marker free,” Ms. Weng. “We don’t touch the patient’s eye like other systems may. This is real-time tracking with real-time guidance. It optimizes the entire workflow, and we are much more precise than the manual markers.” callisto Eye and Z Align The Callisto Eye and Z Align is a modular platform that works seamlessly with the OPMI LUMERA 700 surgical microscope (Carl Zeiss Meditec) to help surgeons align toric IOLs, position incisions and LRIs, and achieve the correct size and shape of capsulorhexis. “This system is nice because it’s very precise and it makes the workflow easier in a busy surgical unit,” Dr. Findl said. “It’s a very straightforward system.” One aspect of the Callisto that Dr. Findl finds valuable is the photograph taken of the vessels around the cornea. The photograph is imported into the computer, which is connected to the surgical microscope, allowing the surgeon to precisely identify these vessels on the live video. The photograph and the video “are actually matched and tracked,” Dr. Findl explained. “When I look into the right eyepiece, on top I see an overlay of these axis lines,” allowing the surgeon to know which axis is the correct axis. “It’s a step toward real virtual surgery,” he added. Another feature of interest is the overlay includes a ring for rhexis size and shape guidance. “You can say you want to have a 5 mm diameter ring, and it will be projected onto your live image while you’re [creating] the rhexis,” he explained. “This will help you guide the rhexis to have a well- centered rhexis of the perfect size. It’s a very simple tool. Obviously, you have to do the rhexis yourself, but you have guidance, and that guidance is very helpful.” Holos Clarity Medical Systems is currently developing a wavefront aberrometer called Holos that shows what Barry Linder, MD, chief medical officer, Clarity Medical Systems, describes as a “wavefront movie”. “Holos is proprietary wavefront technology that is real time. It’s the difference between a movie camera and a still camera,” he explained. “Holos is able to run in real time and process and continuously display wavefront data with refraction.” When designing Holos, Clarity focused on creating a system that was straightforward and easy to use, Dr. Linder said. “Our goal was to ensure we didn’t ask surgeons to do anything differently,” he said. “They don’t have to stop the procedure, they don’t have to have anyone else doing anything, and they don’t have to change their operating distance.” Holos is still in development, but a number of cataract surgeons have used the system in a feasibility clinical study. The response was overwhelmingly positive and enthusiastic, Dr. Linder said. “It’s small compared to other technologies,” he said. “It doesn’t interfere at all with passing instruments. Everyone who has used it has commented on its ease of use. It’s highly intuitive and doesn’t disrupt the procedure in any way.” Clarity can’t comment on when Holos will reach market, but the company does believe the technology is on the horizon. EWAP Editors’ note: Dr. Linder has financial interests with Clarity Medical Systems. Dr. Zaldivar has financial interests with Tracey Technologies. Ms. Weng has financial interests with SensoMotoric Instruments. Drs. Bafna and Findl have no financial interests related to this article. contact information Bafna: drbafna@clevelandeyeclinic.com Linder: barry.linder@alum.mit.edu Weng: chen.weng@smi.de Zaldivar: contact Diana Arbet, darbet@ institutozaldivar.com Tools - from page 33