EyeWorld Asia-Pacific September 2020 Issue

EWAP SEPTEMBER 2020 19 FEATURE and are more likely to fibrose,” Dr. Lewis said. Dr. Lewis mentioned that many drugs that have a mechanism of action based on vasodilation potentially have a similar effect. Dr. Baudouin’s second step is to treat the ocular surface. This can be done with preservative- free artificial tears, cyclosporine, or a low-dose steroid. Steroids, he noted, can raise intraocular pressure (an especially undesired effect for glaucoma patients), thus he recommended short- term use. “You need to balance between risk of the steroid and the interest of decreasing inflammation,” he said. Finally, Dr. Baudouin said his third point is to consider surgery at an earlier stage after surgery. Prevention and the appropriate time for surgery are important to consider.” Dr. Lewis noted that sometimes the bleb itself can be irritating postoperatively to the ocular surface, requiring patients to be on artificial tears. It also can be so large it causes disruption in the even tear flow over the cornea, causing dry spots called dellen. This condition, he said, usually goes away on its own if the bleb shrinks. Considerations for the ocular surface apply to traditional trabeculectomy procedures as well as trabeculectomy-like MIGS, such as the XEN Gel Stent (Allergan) and PRESERFLO (formerly InnFocus Microshunt, Santen), the latter of which is not yet FDA approved. “Whatever the technique— trabeculectomy, tube in the category of MIGS, whatever— the bleb remains a concern for the ocular surface, a concern preop, a concern periop, and also a concern postop,” Dr. Baudouin said. EWAP Reference 1. Baudouin C. Ocular surface and external filtration surgery: mutual relationships. Dev Ophthalmol. 2012;50:64–78. Editors’ note: Dr. Baudouin is professor of ophthalmology, Quinze-Vingts National Eye Hospital & Vision Institute, Paris, France, and has relevant interests with Alcon, Allergan, Aerie Pharmaceuticals, Santen, and Thea. Dr. Lewis practices at Sacramento Eye Consultants, Sacramento, California, and has relevant interests with Aerie Pharmaceuticals, Allergan, and Alcon. Ocular surface disease in a glaucomatous patient. Source (all): Christophe Baudouin, MD, PhD with, potentially, a less invasive technique. “For a patient with uncontrolled glaucoma on two eye drops, rather than adding a new drug or changing for a new drug, it’s probably better to go to surgery,” he said, noting laser trabeculoplasty and several MIGS options available. “Propose surgery earlier than an end-stage glaucoma patient with a poor ocular surface.” Postoperatively, Dr. Lewis said patients take a steroid four times a day for 3–6 weeks. Mitomycin, used intraoperatively, might also be needed postop as well to inhibit fibrosis. “We’ll take a patient 6–8 weeks postop and in the office use mitomycin in a syringe, inject it near the bleb to try to kill any rapidly dividing cells, and that will slow down the fibrosis or stop it,” he explained. Dr. Baudouin said he’s very careful with steroids postop, using them for a short period of time (a few weeks) after surgery. He said he might also use a non-steroidal and prescribes preservative-free artificial tears. “We also have to consider that the bleb is a cause of trauma—stress between the eyelid and the conjunctiva. If the lubrication is not very good, it may also cause discomfort, but again discomfort due to ocular surface disease is not only a question of discomfort but also mechanical stress that can cause inflammatory stress,” he explained. In some cases, the trabeculectomy procedure can help continue improvement of ocular surface conditions. If the ocular surface was damaged by glaucoma medications and those mediations are stopped due to success of the procedure, the ocular surface improves. “The question here is to not do surgery too late. If we wait for too long with a very damaged ocular surface, the benefit of surgery and removal of the drug will be limited,” Dr. Baudouin said. “The eye will be damaged with deep, chronic inflammation, fibrosis, and the bleb will not function properly, so it means it might be necessary again to use medication to control pressure