EyeWorld Asia-Pacific September 2017 Issue

digits. In general, it is a balance be- tween efficacy and risk. The more IOP lowering you are looking for, the more risk is associated with it. A more modest IOP response comes with a lower amount of risk,” he explained. Dr. Lewis agreed. “MIGS are much safer than traditional glaucoma surgeries and achieve reasonable pressure reduction with minimal risk. We are becoming comfortable with how and when to use them. I think all of them will ultimately be used with or without cataract surgery, and they will be used for a broader range of glau- coma. Now we are trying to figure out the right candidates for each treatment and how to best facili- tate achieving optimum pressure control. It sounds a lot easier than it is. The bottom line is the way the wound heals.” Although MIGS offers benefits compared to traditional glaucoma surgeries, there are still instances in which traditional surgeries are preferred. “If patients are not candidates for MIGS, I use a trab- eculectomy approach. Additionally, the use of drainage devices is going to continue. However, MIGS will ultimately erode the numbers as we get more comfortable and begin to find ways to more effectively get pressure control. I am still doing traditional surgery, but it’s going to be interesting over the next 5 years as we adopt these new procedures, begin to achieve good pressure control with a much safer profile, and get full reimbursement,” Dr. Lewis said. Tips for success with MIGS According to Dr. Lewis, the key to success with MIGS is getting com- fortable in the operating room with gonioscopy. “The big challenge for non-glaucoma surgeons is that they have to get comfortable using a gonioprism in their non-dominant hand without pushing too hard and getting the optimal view. It requires proper head position and maximizing the magnification. All of these fundamental tips are crucial to getting the best view. People who don’t take the time to get the best view are compromising their outcomes. Fundamentals are important even before you implant the device,” he said. Before performing MIGS, Dr. Greenwood recommended getting comfortable with the anatomy of the angle. “We encourage surgeons to practice in the clinic and do gonioscopy so that they can get a good feel for the angle structures. Then start doing them on your routine cataract cases. At the end of the day, taking a couple of extra minutes to practice goniotomy on patients in the operating room can be helpful. Having a good view and being comfortable with the ma- neuvers that are needed to do these procedures is the most important aspect of surgery,” he said. Reay Brown, MD , Atlanta, said that staining the trabecular meshwork with trypan blue has helped his technique. “The idea is to stain the meshwork the same way that you would stain the an- terior capsule in a case where you have either a dark brown nucleus or a white nucleus,” he said. “The idea is to light up the trabecular mesh- work by staining it with trypan blue. This is a big help because it shows you where the canal is and it reveals the posterior wall as you are implanting the iStent, so you know you are implanting it at the right depth. It identifies what you are aiming for, and it also gives you a positive sign that you have found the right channel.” Who should perform MIGS? According to Dr. Berdahl, there are three types of surgeons who consider incorporating MIGS in their practices, and they all have a different question. “Comprehen- sive ophthalmologists question whether they see enough of these patients to perfect their technique. Data indicate that 20% of patients undergoing cataract surgery have a concurrent diagnosis of glaucoma, so I think the answer there is yes. High-volume cataract surgeons question whether they want to get into the MIGS game, and I think that’s a fair question. If they don’t, I think that’s OK. However, even if you don’t offer MIGS as a high- volume cataract surgeon, if there is a patient with cataract and glau- coma, you should let him or her know that there is a good option out there. The third surgeon is the glaucoma specialist who questions whether MIGS can get the pres- sure low enough for the advanced glaucoma patients, and the answer is maybe. In general, it is a good place to start because it is so safe. If it doesn’t get the pressure low enough, you can move on to a more aggressive but riskier glau- coma surgery,” he explained. Today, MIGS procedures are al- lowing surgeons to treat glaucoma earlier and more safely than tradi- tional glaucoma procedures. “Surgeons are going to find their preferred MIGS surgery,” Dr. Greenwood said. “As time goes by and more data become available, we may learn that some are supe- rior to others. Right now, surgeons have to understand what data are available and decide what they think is an equal balance of safety and efficacy for each individual patient.” EWAP Editors’ note: Dr. Berdahl has finan- cial interests with Glaukos, Alcon, Allergan, Johnson & Johnson Vision (Santa Ana, California), and New World Medical. Dr. Brown has finan- cial interests with Glaukos. Dr. Lewis has financial interests with Allergan, Glaukos, Alcon, Ivantis (Irvine, Cali- fornia), and Aerie Pharmaceuticals (Irvine, California). Dr. Greenwood has no financial interests related to his comments. Contact information Berdahl: john.berdahl@ vancethompsonvision.com Brown: reaymary@comcast.net Greenwood: michael.greenwood@ vancethompsonvision.com Lewis: rlewiseyemd@yahoo.com September 2017 24 EWAP SECONDARY FEATURE Tips and techniques – from page 23