Eyeworld

EW FEATURE 66 Glaucoma and the cataract patient • February 2017 AT A GLANCE • Pressure-reducing effect elevates lens-based glaucoma surgery to the forefront of glaucoma treatment. • Clear lens extraction shows greater efficacy and cost effectiveness than peripheral laser iridotomy, according to the EAGLE study. • Not all new study results definitively impact physicians' clinical practice. • Lens removal is effective in eyes with less than 270 degrees of PAS. by Stefanie Petrou Binder, MD, EyeWorld Contributing Writer Contrasting perspectives prevail despite new evidence in angle closure glaucoma G laucoma specialists handle primary angle closure glaucoma (PACG) on a patient-to-patient basis, as no single avenue of treatment can cover all the scenarios encountered in this disease. Lens extraction using phacoemulsifica- tion is a new approach for PACG management, often alleviating high IOP, opening the anterior chamber angle, and improving quality of life. Some glaucoma doctors, however, are less convinced than others about the efficacy of lens extraction—in the absence of cataract—as the best glaucoma patients avoid the worsen- ing of their pressure control caused by these now avoidable complica- tions. Does a diagnosis of glaucoma change the indications for cataract surgery? Clearly, yes. There seem to be few clinical situations in PACG in which lens removal is not beneficial and preferred over laser treatment or a phaco trabeculectomy." Dr. Brown's views coincide with the newest evidence in support of lens extraction from the recently published, multicenter, random- ized, controlled Effectiveness in Angle Closure Glaucoma of Lens Extraction (EAGLE) study. 1 EAGLE investigated the benefits of early clear lens extraction in 419 patients newly diagnosed with primary angle closure and IOPs in excess of 30 mm Hg, or with PACG, who underwent either lens extraction or laser iridot- omy (LI). It demonstrated the great- er efficacy and cost effectiveness of clear lens extraction over peripheral LI and suggested that clear lens ex- traction be considered as an option for first-line treatment in PACG. Eyes with angle closure will typically present as short eyes with shallow anterior chambers. It is thought that the increasing thick- ness of the aging lens also contrib- utes to a progressive narrowing of the angle. Meanwhile, LI widens the anterior chamber angle, some degree of iridotrabecular contact persists in most patients, and angle closure may progress despite an iridectomy. Dr. Brown explained, "The anato- my of angle closure eyes supports a therapeutic role for lens removal. Removal of the lens clearly deepens the chamber and opens the angle. Combining the anatomical evidence with the clinical success of cataract surgery has led to discussions about whether clear lens extraction should be recommended for patients with angle closure. There are no studies on the role of clear lens extraction in treating angle closure, however, if the anterior segment anatomy is the problem, and it frequently is, removing a clear lens may have the same positive effects as removing a cloudy lens." In a review of studies surround- ing lens extraction in PACG, 2 Dr. Brown demonstrated a strong body of evidence in favor of cataract surgery for angle closure patients to reduce IOP and dramatically reduce the future risk of IOP spikes and acute attacks. Cataract surgery was found to be a more effective treat- ment for an attack of acute primary angle closure than laser iridotomy. It also demonstrated better outcomes when compared to phaco trabe- culectomy, which showed a higher complication rate than phaco alone. He showed evidence that described an increased risk of 50% for requir- ing cataract surgery in patients un- dergoing trabeculectomy, with the added risk of the subsequent cataract Debating the benefits of lens extraction in PACG Monthly Pulse Glaucoma and the cataract patient T he topic of this Monthly Pulse survey was "Glaucoma and the cataract patient." We asked, "What is your topical steroid protocol for a glaucoma patient having cataract surgery?" The majority of respondents to this survey said, "It is the same as with routine cataract patients." When asked if they discontinue the use of prostaglandin analogues in glaucoma patients having cataract surgery, the majority said no. We then presented this scenario: "You have a patient with angle closure glaucoma, s/p PI, with an IOP of 20 to 25 mm Hg on maximum medications. You think the nerve in this eye is more cupped than the fellow eye, and the visual field may be showing some very early dam- age. The vision is 20/20- but with glare testing, it drops to 20/30-. The patient has no complaints about vision. What will you do?" The majority of respondents to the survey said they would do cataract surgery alone. When asked what worries them the most about implanting a MIGS device in a cataract operation, most physicians in this way to reduce IOP in these patients. Reay Brown, MD, founding partner, Atlanta Ophthalmology Associates, Atlanta; Joseph Panarelli, MD, glaucoma fellowship director and associate residency program director, New York Eye and Ear Infirmary of Mount Sinai, New York; and Robert Feldman, MD, clinical professor and chairman, Ruiz Department of Ophthalmology and Visual Science, University of Texas McGovern Medical School, Houston, spoke with EyeWorld about their treatment preferences for PACG. All for it According to Dr. Brown, doctors are now looking at the glaucoma patient in new ways. The role for cataract surgery in angle closure is expand- ing, and he thinks that the pressure reduction achieved by modern phacoemulsification has elevated lens-based glaucoma surgery to the forefront of glaucoma treatment. As most patients will eventually need cataract surgery, doctors have all the more reason to factor lens removal into their overall treatment plan. "We see patients everyday in our practices from the pre-phacoemulsi- fication era with peripheral anterior synechiae, secondary angle clo- sure, chronic inflammation, and other problems from extracapsular surgery that contribute to their glaucoma," Dr. Brown said. "Mod- ern phacoemulsification can help survey said, "Not achieving enough of an IOP reduction." Finally, we asked, "Which of the following have you found to be most helpful in improving the ocular surface prior to cataract surgery in patients with glaucoma?" The most popular answer was frequent artificial tears.

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