EyeWorld India March 2012 Issue

54 EW DEVICES March 2012 OptiMedica Alcon LenSx LensAR Technolas/ B+L Interface design Liquid optics (immersion lens) Curved lens Robocone (immersion lens) Curved lens Imaging type 3D spectral domain OCT 3D OCT 3D-CSI (confocal structured illumaination) Online OCT Ocular surface identification Automatic or user-adjustable Manual Automatic Manual Integrated chair Yes No No Yes System dimensions (w/o bed) 35 x 65” 48 x 62” 78 x 36” (extended) 41 x 81” System origin Laser cataract surgery Femtosecond LASIK (intralase) Presbyopia treatment Femtosecond LASIK This month’s column discusses the latest in femto for phaco T he latest phaco device innovation to come to market or be in development is the advent of the femtosecond laser for refractive cataract surgery. Podium presentations have touted the ability of the lasers to create more precise incisions and capsulorhexis, but a hefty price tag and no long-term data (yet) has lead to continued debate. With these devices estimated to cost anywhere from US$400,000 to US$550,000 and service fees after the first year expected to be about 10% of the purchase price, Jonathan H. Talamo, MD, associate clinical professor of ophthalmology, Harvard Medical School, Boston, Mass., USA, said relevant indications and regulatory approvals may be crucial for both manufacturers and those debating which system to purchase. Of the top four companies producing these devices, only Alcon’s LenSx (Fort Worth, Texas, USA/ Hünenberg, Switzerland) has regulatory clearance in the U.S. for capsulotomy, lens fragmentation, relaxing incisions, and cataract incision. The LensAR system (Winter Park, Fla., USA) has approval for capsulotomy and lens fragmentation, and both Catalys (OptiMedica, Santa Clara, Calif., USA) and Victus (Bausch + Lomb (B+L), Rochester, NY, USA/Technolas, Munich, Germany) do not yet have any U.S. regulatory approvals. In Europe, OptiMedica has received the CE mark for capsulotomy and lens fragmentation, and Victus has received the CE mark for LASIK flap, astigmatic keratotomy, INTRACOR, capsulotomy, and lens fragmentation. At the 2011 American Academy of Ophthalmology (AAO) meeting, William W. Culbertson, MD, professor of ophthalmology, Bascom Palmer Eye Institute, Miami, Fla., USA, said during a press conference on the topic that ultrasound energy use “was reduced by 45% in the laser pre-treated eyes compared with the eyes receiving standard phaco. Also, surgical manipulation of the eye was reduced by 45% in eyes that received laser pre-treatment as compared to manual standard surgery.” As noted in Table 1, there are significant differences among the devices, namely in the areas of docking strategies, imaging, and ergonomics, Dr. Talamo said. Below, EyeWorld provides a brief synopsis of the lasers from various presentations (podium and otherwise) during the 2011 AAO meeting. Catalys Barry Seibel, MD, Seibel Vision Surgery, Los Angeles, Calif., USA, said compared with manual techniques, “we had a tenfold decrease in deviation from intended diameter” by using the Catalys. He presented results from a 29-patient study, where one eye was treated with the Catalys for capsulotomy and lens fragmentation and the other eye was treated manually. The system’s liquid optics interface also allows for optimal lens pre-fragmentation, he said. “Because there is no corneal distortion, the intraocular pressure rise is minimal,” he said; this allows for “both precise optical coherence tomography (OCT) imaging and accurate, predictable, and energy- efficient laser delivery”. LensAR Louis D. “Skip” Nichamin, MD, Laurel Eye Clinic, Brookville, Pa., USA, said a major benefit of the LensAR system is its “proprietary imaging; it’s not OCT but 3D-confocal structured illumination.” Advantages to this type of imaging are its ability to provide a three-dimensional reconstruction of the anterior ocular structures through ray tracing while providing biometric data, including corneal, anterior chamber, and lens metrics, he said. Laser systems for refractive cataract surgery by Michelle Dalton EyeWorld Contributing Editor Mark Packer, MD, clinical associate professor, Oregon Health & Sciences University, Portland, Ore., USA, found that when the LensAR lens fragmentation was used in 225 eyes, there was no loss of endothelial cells, while 63 eyes that received standard treatment had cell loss of 1 to 7%. Differences were statistically significant at the 90% level for grades 1 and 3, but not grades 2 and 4, he said. LenSx Jorge L. Alio, MD, professor and chair of ophthalmology, Miguel Hernandez University, Alicante, Spain, described his technique of sub-1-mm incisions, a process he dubbed “Femto-MICS”. A prospective study evaluated the reproducibility and refractive impact of corneal incisions made with the LenSx for both standard and microincisional surgery; the incision width was between 1 and 1.3 mm, with follow-up at 1 month. “The incisions are always self- sealing and induce no refractive Table 1. Key system figures for femtosecond lasers for refractive cataract surgery Source: Jonathan H. Talamo, MD