The Leading Cause of Visual Field Loss

As those close to glaucoma know, many obstacles are inherent to the management of this disease. Glaucoma is multifactorial, complex, progressive, and often asymptomatic until irreversible damage has occurred. Each glaucomatous eye requires careful consideration, and treatment is far from one-size-fits-all. Systemic barriers have also long complicated patient access to care.

The introduction of MIGS represented a significant step forward in the management of glaucoma and in our ability to better tailor care to the individual. Options that were less burdensome than medical therapy and less invasive than trabeculectomy and tube shunt surgery were welcome and overdue additions.

In recent months, another significant barrier to glaucoma care was introduced when WPS Government Health Administrators, a Medicare Administrative Contractor, published a local coverage determination (LCD) for MIGS. This LCD deemed several procedures investigational, ultimately threatening to eliminate insurance coverage in a number of states—much to the dismay and confusion of those who specialize in this disease and use these procedures regularly.

In somewhat of an explanation of how this determination was made, the LCD states: “A Contractor Advisory Committee (CAC) Meeting on [MIGS] was held on 1/5/2023 hosted by Palmetto, CGS, NGS, Noridian, and WPS. The input from subject matter experts will be referenced through this policy.” In this Contractor Advisory Committee meeting, questions were posed to ophthalmologists about the procedures in question and about glaucoma in general.

One standout from the transcript¹ is a question posed by the moderator—an internist and Medicare Administrative Contractor medical director. She asked, “There’s been burgeoning various medications added over the decades, lots of new procedures, and yet every glaucoma study I read starts out the same way, and that is [that] glaucoma is the leading cause of visual field loss. But how come? That never seems to budge. How come that’s always the conclusion, despite all the additional therapies?”

No fault to the moderator for asking; glaucoma is perplexing, even to glaucoma specialists. The fault lies in the processes and systems for reaching such impactful conclusions about its care—in the evidence that is reviewed, the sources that are consulted, and the decision-makers who have the final say. The LCD implies that the basis for restricting the use of procedures such as canaloplasty, goniotomy, and endocyclophotocoagulation was a lack of evidence showing their superiority to trabeculectomy or tube shunt surgery.

We know the value of these procedures, and we know that it is not just theoretical but evidentiary. We see the value in our studies, in our clinics, and in each patient we treat. This issue of GT focuses on the patient experience, with this decision and with glaucoma in general. Glaucoma is complex, but perhaps we confidently know one thing to be true: Limiting access to evidence-backed procedures that help us to manage the disease is no way to stop it from being the leading cause of visual field loss. What is the way is having access to a range of treatment options that can be used to help the individual patient in our chair—the one experiencing the effects of this disease.