Eyeworld

SEPTEMBER 2023 | EYEWORLD | 61 G COMPLICATED CASES by Ellen Stodola Editorial Co-Director About the physicians Alexis Kassotis PGY-2 Ophthalmology Resident Edward Harkness Eye Institute at Columbia University Medical Center New York, New York Mary Qiu, MD Glaucoma Specialist Department of Ophthalmology and Visual Science at University of Chicago Chicago, Illinois Aakriti Garg Shukla, MD Glaucoma Specialist Edward Harkness Eye Institute at Columbia University Medical Center New York, New York Catherine Sun, MD Glaucoma Specialist Department of Ophthalmology at University of California, San Francisco San Francisco, California Jessie Wang, MD PGY-4 Ophthalmology Resident Department of Ophthalmology and Visual Science at University of Chicago Chicago, Illinois A ccording to glaucoma specialists Mary Qiu, MD, Aakriti Shukla, MD, and Catherine Sun, MD, neovascular glaucoma (NVG) is an aggressive, secondary glaucoma that develops in the setting of retinal ischemia. Dr. Sun discussed signs and strategies to manage this condition, and ophthalmology residents Alexis Kassotis, MD, and Jessie Wang, MD, also shared their thoughts on this topic. Signs and characteristics The most common etiologies that lead to NVG are proliferative diabetic retinopathy (PDR), ret- inal vein occlusion (RVO), and ocular ischemic syndrome (OIS), 1 Dr. Sun said. "Many patients are diagnosed with NVG when they present with an acute rise in IOP, severe eye pain, and/ or decreased vision," she said. "These symp- toms are often due to neovascularization of the angle (NVA), which obstructs aqueous outflow through the normal drainage pathway of the eye and leads to elevation in IOP and severe pain." Aside from the normal eye exam features, it is important to look for neovascularization of the iris (NVI) and NVA on slit lamp exam before dilation and by performing gonioscopy, Dr. Sun said. Gonioscopy can tell you if there is NVA or synechial angle closure. Other signs of NVG include conjunctival hyperemia or corneal edema if an acute rise in IOP occurs, although this may not be present if the IOP elevation is insidious. Hyphema or microhyphema often oc- cur due to bleeding of fragile anterior segment vessels, and ectropion uveae or corectopia may be seen if synechiae exist, 2 she added. A dilated exam should be performed after gonioscopy to determine if there are other complications such as vitreous hemorrhage, retinal detachment, or macular edema, and to help determine the etiology of the condition. Early stage disease is characterized by an- terior segment neovascularization with normal IOP. NVI usually starts at the pupillary border with vessel growth in a disorganized fashion. In some cases, NVA can be present without NVI. 2 As a fibrovascular membrane continues to grow over the trabecular meshwork, IOP can rise, Dr. Kassotis said. In the earliest stages, there are no peripheral anterior synechiae, but as the disease progresses, peripheral anterior synechiae can develop. "The presence of synechiae leads to partial or complete angle closure, while their absence denotes open angle disease," she said. "At present, this terminology exists with or with- out the presence of glaucomatous optic neu- ropathy (i.e., once there is glaucomatous optic neuropathy, it is termed a 'glaucoma')." Dr. Sun, along with Dr. Qiu and Dr. Shukla, advocate for a consensus panel to standardize the nomenclature for NVG. Management Dr. Sun, Dr. Qiu, and Dr. Shukla said that the management of NVG includes: 1) controlling the IOP, and 2) addressing the underlying dis- ease responsible for the neovascularization. "To control the IOP, topical and oral medica- tions are used initially. If medical therapy is not enough, which is usually the case, or if patients need to be placed on oral carbonic anhydrase inhibitors, laser or surgical treatments should be offered," she said. "These traditionally include cyclophotocoagulation (CPC), aqueous shunts, or trabeculectomy." Dr. Sun said that valved aqueous shunts are generally preferred as the definitive treatment given high rates of failure with trabeculectomy and immediate pressure lowering with valved compared to non-valved aqueous shunts. CPC is usually reserved for patients with poor visual potential and may have a temporary effect. "In rare cases, I will perform CPC in an emergent situation in the clinic or emergency room if medications are not effective and we are un- able to take the patient to the operating room urgently," she said. "If the effect of CPC is not enough, patients will generally get a subsequent aqueous shunt." Dr. Qiu said that in her practice pattern, in eyes with total synechial angle closure at the time of NVG presentation and active anterior segment neovascularization, she will perform gentle CPC in the OR setting with judicious steroids, regardless of visual potential. "I agree if the effect of CPC is not enough to control the IOP, patients will get an aqueous shunt later," she said. "I prefer to use a non-valved aqueous The convoluted condition of neovascular glaucoma continued on page 62

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