EyeWorld Asia-Pacific March 2017 Issue

34 EWAP SECONDARY FEATURE March 2017 the contralateral eye. Dr. Panarelli encourages the use of certain MIGS devices in patients with PACG, assuming synechiae do not hamper visualization of the outflow pathway, which a number of MIGS devices rely on for strategic stent placement. Goniosynechialysis can help restore aqueous flow, reduce IOP, and possibly even allow later stent implantation in the primary outflow pathway. It is thought to be most effective when performed early on in the process, i.e. within 6 months of synechiae formation. When present for greater periods of time, however, breaking synechiae may cause more damage to the canal network than relief. Using the XEN Gel Stent (Allergan, Dublin, Ireland) in cases where the physiologic outflow through Schlemm’s canal and the trabecular meshwork is compromised offers surgeons a new treatment option. The XEN stent shunts fluid from the anterior chamber to the subconjunctival space. Although traditionally glaucoma surgeons have avoided shunt placement in the already shallow anterior chamber out of concern about endothelial cell loss, the 6mm XEN Gel Stent just barely protrudes into the eye and should be a safe, viable alternative in patients with PACG. Tell all: PAS For Dr. Feldman, who does sometimes perform clear lens extraction for angle closure, the EAGLE study does not always translate. “Not everyone has pressures of 30 mmHg like the participants of the EAGLE study. Most patients that I manage don’t. We are catching them before that happens and treating them before their pressures go up that high. I do not perform lens removal in PACG because of high pressure, but rather to fix the anatomy to prevent additional angle closure. The determining factor is how much peripheral anterior synechiae (PAS) they have and if I think I can get the closed angle working again,” he told EyeWorld . Lens removal can be effective in lowering IOP in PACG patients who have less than 270 degrees of PAS. Dr. Feldman couples lens removal with additional measures, as needed, to reduce the IOP or open the angle, depending on the anatomy captured on imaging. He considers cataract surgery alone in patients with even up to 270 degrees of PAS, without the need for additional glaucoma surgery. With more than 270 degrees of PAS, lens removal may not suffice to lower IOP because of the paucity of viable trabecular meshwork draining the eye, and he will opt for glaucoma surgery alone if there is no visually significant cataract and combined if there is. Dr. Feldman thinks it is important to address the potential causes of angle closure when possible. While cataract surgery may deepen the anterior chamber, it may not be the lone cause of the problem. If the angle “New study results do not change my practice patterns that quickly. I am always open to the results of new studies, but I think you have to look at each individual patient as the results/conclusions do not apply directly to every patient you see. Not every new study—even with encouraging results—will impact your clinical practice in a definitive way. In the end, you still need to do what is best in your hands.” Looking at the clinical impact of eight landmark glaucoma trials, Dr. Panarelli noted substantial differences in the way randomized clinical trials affected actual clinical practices, owing to factors like study timing, design, conduct, and interpretation of results. 3 Acknowledging that eye doctors want to provide the highest standards of care, he explained, “We want to be on the cutting edge, but we know that for our patients it isn’t always the newest thing out there that is gaining a lot of press that is best. We have to look at these studies, critically review them, and see if this is best for our patients, especially if we are talking about doing something invasive, when we otherwise might not have. I am not 100% ready to change my ways and perform cataract surgery routinely in this more challenging patient population.” That said, Dr. Panarelli notes that he is open to changing his approach, especially if the patient has had a less than ideal outcome with a previous method of treatment in are unfounded because, in practice, truly clear lenses are not common in patients who have had acute attacks or have chronic glaucoma, and who will usually also have multiple risk factors.” Grain of salt As would be expected, there is another valid side to this argument. To glaucoma specialist Dr. Panarelli, cataract surgery is still more of a solution for patients with visual complaints due to cataract and to be considered with caution for PACG patients. He told EyeWorld , “I was trained to perform cataract surgery on people with visual complaints that impinge upon their daily activities—early lens extraction as a treatment for glaucoma is a completely new approach for me. Although there have been studies showing that lens removal can reduce the IOP in patients with open- and closed- angle glaucoma, many of us prefer to stick to our classic treatment algorithm when managing glaucoma, instituting medical and laser therapy first and then moving to traditional glaucoma surgery if the intraocular pressure is too high for the degree of disc damage.” Dr. Panarelli’s first choice for treatment of a narrow angle is a laser iridotomy. If there is elevated intraocular pressure, he begins medication and considers iridoplasty, especially in those patients with plateau iris syndrome or nanophthalmos. If these measures do not adequately reduce the IOP, he considers doing filtering surgery. He explained, Debating - from page 29