Eyeworld

EW FEATURE 44 Microinvasive glaucoma surgery (MIGS) • May 2016 • In the growing number of MIGS options, some procedures that don't involve an implant could present a benefit. • Several options can perform ab interno trabeculotomy using slightly different techniques, while others reduce aqueous inflow. • Patient selection and the surgeon's level of comfort will be key for successful outcomes in lowering IOP for mild to moderate glaucoma patients. AT A GLANCE by Liz Hillman EyeWorld Staff Writer Several techniques available to improve outflow or reduce inflow and lower IOP W hen ophthalmologists consider taking a patient with mild to moderate glaucoma to the next level of treatment, they're seeing something they didn't have before: options. While there used to be little in between topical medications and surgeries like trabeculectomy and tube shunts, the advent of microin- vasive glaucoma surgery (MIGS) has begun to fill this gap. With many implants and procedures making their way to market within the last decade and more in the pipeline, physicians are interested in new techniques to lower IOP but are also quick to note where there is limited data in some cases. "We are at an interesting and good place in the evolution of microinvasive glaucoma surgery be- cause we have many options," said Nathan Radcliffe, MD, New York University Langone Ophthalmology Associates, New York. George Tanaka, MD, San Francisco, agreed, saying MIGS has "great promise" but "more studies are needed before we can make treat- ment recommendations grounded in evidence-based science." There are procedures targeted at reducing inflow—endoscopic cyclophotocoagulation and trans- scleral cyclophotocoagulation (most recently with the micropulse technique)—and those that address depending on the parameters of the physician's practice, devices or implants may not be covered and may not be available to all patients from an insurance perspective. In other cases, insurance may indicate that the implant is covered and then decide not to pay after the fact, leaving the physician and patient in an awkward position. "If a similar procedure can be performed without any implant, this potential problem is avoided," he added. outflow. For the latter, there are im- plants—the iStent (Glaukos, Laguna Hills, California), for example—and there are implantless procedural op- tions—the Kahook Dual Blade (New World Medical, Rancho Cucamonga, California), Trab360 (Sight Sciences, Menlo Park, California), Trabectome (NeoMedix, Tustin, California), and iTrack 250A Microcatheter (Ellex, Adelaide, Australia) to name a few. "While [implants] are great, they have some problems," Dr. Radcliffe said. "To begin with, Procedures without an implant could present medical disadvantages compared to MIGS using a stent as well. Because of the substantial pro- spective, randomized data required by the FDA prior to approval of an implant, the physician would typi- cally have more information about both the safety and efficacy of the implant. Many options for MIGS without an implant Endoscopic cyclophotocoagulation is pointed at the bottom of the ciliary body and used to rotate it posteriorly in angle closure with associated plateau iris. Trab360 can complete up to a 360-degree cut in the trabecular meshwork to improve outflow and lower IOP. Source: Arsham Sheybani, MD continued on page 46

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