EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/119916
April 2013 clear view into the angle," Dr. Brown said. All current clinical trials are now evaluating two stents, but "one will work for many of our patients." Dr. Samuelson said that for now he only implants one stent and ad- Douglas Rhee, MD Thomas Samuelson, MD Lens (Transcend Medical, Menlo Park, Calif.). The iStent "increases outflow and is currently the smallest medical device to be implanted in the human body," he said. In the angle there is a small risk of damaging the corneal endothelium if the device is not placed properly. Although the iStent is approved for just one implant, recently published studies indicate that two devices implanted simultaneously may provide additional benefit. "It will be interesting to see over time if two microstents are more efficacious than just one implant," Dr. Vold said. Of the web participants, 46% said the "jury is still out" on the iStent, and only 25% think it is moderately safe and efficacious; 27% felt the Trabectome is a niche device. Hands-on experiences The advantage of the iStent is surgeons can cannulate the canal "with virtually no destruction," Dr. Samuelson said, adding he's using Trabectome a bit less often in favor of the iStent, primarily due to the fact that it is tissue friendly. Dr. Brown mostly combines the Trabectome with cataract surgery. "I'm a fan of trabecular bypass," he said. "I think we're finally tapping into it with the iStent, and I enjoy the elegance of the procedure and the efficiency of being able to put something into the canal without requiring any other supporting systems." Dr. Vold said learning the ocular anatomy and where to place the devices is the most difficult part of MIGS. He believes that differences in surgical success among surgeons may be explained in part by the placement of the devices in relation to the collector channels, as well as patient selection. EW NEWS & OPINION 17 vises surgeons to become comfortable placing a single stent before entertaining the prospect of placing multiple stents. He prefers clear corneal temporal incisions and continued on page 18 Steven D. Vold, MD "To date, I haven't had any safety issues with these devices," Dr. Samuelson said. "Even so, it is important to be mindful of good surgical principles, for example some surgeons may fail to evacuate the viscoelastic; be wary of IOP spikes." INTRODUCING NEW Femtosecond Cataract Instruments E4929 Daya Femto Trans-Lens Hydrodissection Cannula Uniquely Designed to Help Create a Fluid Wave During Hydrodissection Still to come The Hydrus Microstent (Ivantis, Irvine, Calif.) provides a flexible canal scaffold that dilates and permanently supports Schlemm's canal, Dr. Vold said. "The data here is quite promising," he added. "I've been impressed with how consistently we can get pressures into the mid-teens." The CyPass Micro-Stent (Transcend Medical) just completed a study that enrolled 500 patients in the U.S., he said. "This devices increases uveoscleral outflow and is used in combination with cataract surgery," Dr. Vold said. The XEN Glaucoma Implant (AqueSys, Aliso Viejo, Calif.) takes a classical outflow approach with minimized trauma and complications. It creates a low, posterior, diffuse filtration bleb, and studies outside the U.S. have established safety and efficacy, Dr. Vold said. For all of these devices, the surgeons stressed the importance of getting the devices into the proper locations; if placed correctly they can lower IOP up to 35-38% and have those levels maintained for up to a year, resulting in a substantial reduction in glaucoma medication use. When to use Dr. Brown prefers to implant the iStent after cataract removal. "You need to have some positioning of the head a bit more nasal to get a E1789 Hu Femto Incision Spreader Curved Shaft & Micro-Spreader Tip Designed to Easily Insert Through Femtosecond Incisions E0645 Hu Capsule Polisher Designed for Flexibility & Ease of Use in Removing Lens Epithelial Cells E4940 Hu Femto Hydrodissection Cannula Features a Flattened Beveled Tip to Insert Under the Capsule to Direct a Fine Concentrated Fluid Stream During Hydrodissection SEE MORE OF OUR FEMTOSECOND INSTRUMENTATION AT WWW.STORZEYE.COM CALL YOUR INSTRUMENT SPECIALIST AT 1-800-338-2020 TO ORDER AND FOR MORE INFORMATION N FOR M INFORMATION F AT ®/™ are trademarks of Bausch & Lomb Incorporated or its afliates. © Bausch & Lomb Incorporated. are trademarks Bausch Lom Incorporated omb m Bausch Lomb Incorporated.