Eyeworld

EW FEATURE 56 Microinvasive glaucoma surgery (MIGS) • May 2016 by EyeWorld staff because they have to pass that cost on to the patient, whereas if they perform a surgery like a trabeculec- tomy or a deep sclerectomy, there is no implanted cost to pass on to the patient," Dr. Radcliffe said. Interestingly, 50% of respon- dents do not plan to offer MIGS or are undecided. Dr. Samuelson thinks that it takes an adequate volume to feel comfortable implanting MIGS devices. "Some surgeons may not adopt because they don't feel that they will reach that critical mass/ volume to be proficient at the proce- dure. Some of the MIGS procedures currently in the pipeline will make insertion easier so adoption may increase," he said. Dr. Radcliffe said there is a combination of factors responsible for the adoption of MIGS. "There are some surgeons who have no one around to teach them this technology. The number of surgeons who plan to offer MIGS is going I predict they will expand their in- dications, and the group for whom they recommend the iStent will increase," he said. Physicians were then asked, "Which of the following best describes your use of/interest in MIGS?" Of the survey respondents, 24% currently implant MIGS. U.S. ophthalmologists were much more likely to use MIGS (29% for U.S. physicians compared to 17% for non-U.S. physicians) (Figure 2). According to Dr. Samuelson, the survey result that U.S. physicians are more willing to use MIGS than non- U.S. physicians is most likely related to the willingness of third-party payers to cover the device expense. Dr. Radcliffe also thinks it has to do with economics. "I think it may have to do with patterns of cost efficacy in practice internation- ally. When I was teaching across eastern Europe, I learned that many surgeons don't place tube shunts twice as many glaucoma patients per month (53) as non-U.S. doctors (27). Of those surveyed, 29% reported seeing 50 or more glaucoma patients per month. When asked what percentage of all of their cataract patients are can- didates for a MIGS procedure, 8% was the average response (10% for U.S. physicians and 5% for non-U.S. physicians) (Figure 1). Dr. Radcliffe said that any pa- tient who uses medication to control IOP and is undergoing cataract sur- gery is a MIGS candidate. "However, when looking at the more aggressive surgeries such as trabeculectomy and tube shunts, in my practice, the severity of the disease determines whether patients have a tube shunt surgery or MIGS," he said. According to Reay Brown, MD, Atlanta, "The iStent [Glaukos, La- guna Hills, California] is much safer than any other non-MIGS glaucoma operation, such as a trabeculectomy or tube shunt surgery. Eye drops have big problems with compliance and disfiguring side effects—redness, discomfort, skin changes, etc. Per- forming an iStent and cataract oper- ation lowers pressure. So the clinical benefit of iStent/cataract surgery is that the patient achieves a pressure reduction safely without problems with compliance or damage to the ocular surface." He recommends an iStent for any glaucoma patient undergoing cataract surgery who takes medica- tion for glaucoma—even 1 eye drop. "This is more than 95% of glaucoma patients having cataract surgery. The goal is to lower the IOP and/ or reduce the number of eye drops. However, I do not recommend an iStent for patients who are on mul- tiple medications with uncontrolled pressures. This group is less than 5% of glaucoma patients receiving cataract surgery, and these patients may need a trabeculectomy or tube shunt. The difference in utiliza- tion rates among surgeons using the iStent is explained by whether they recommend the iStent for all glaucoma patients receiving drops or whether they do it only in a subset—those with IOPs not quite controlled but without advanced glaucoma damage. As surgeons get more familiar with the iStent and see how much it helps lower IOP, ASCRS members weigh in S urgical glaucoma treat- ments have traditionally been reserved for patients with advanced disease be- cause they are riskier than treatments with medications and lasers. However, new microinvasive glaucoma surgeries (MIGS) are gain- ing popularity because they involve much less risk than other surgical treatments. "MIGS are far safer than con- ventional surgery, albeit less effi- cacious. Even so, there is adequate efficacy to reduce the need for medications. Simple preoperative regimens can often be eliminated altogether, and more complex preop regimens can become more simpli- fied," said Thomas Samuelson, MD, Minneapolis. He explained that ideal MIGS candidates have less advanced glaucoma, do not have extremely elevated IOP, tolerate at least some medication, and have an operable cataract and an open angle, or at least an angle that will be ade- quately open once the cataract is removed. "We have to recognize that we are in an evolving landscape with MIGS and cataract surgery right now, just as the cataract refractive surgery landscape has been evolv- ing," said Nathan Radcliffe, MD, New York. "If you are a cataract surgeon operating on glaucoma patients, you need to let them know that there are options and safe procedures to address the intraocu- lar pressure at the time of cataract surgery. I think all rational patients with glaucoma who are using medication would want something safe to be done for their glaucoma at the time of cataract surgery. This demand for MIGS is going to induce more traditional cataract surgeons to perform MIGS at the time of cataract surgery." In the 2015 ASCRS Clinical Survey, ASCRS members were sur- veyed about their adoption of MIGS in cataract patients. Physicians were asked, "Ap- proximately how many patients do you see per month that you would consider as having glaucoma?" The average was 41, with U.S. ophthalmologists seeing almost MIGS adoption in cataract patients Figure 1. The survey asked, "What percent of all of your cataract patients would you estimate are candidates for a microinvasive glaucoma surgery (MIGS) device?" Figure 2. The survey asked, "Which of the following best describes your use of/interest in microinvasive glaucoma surgery (MIGS)?"

• Cover