Changed Minds, Changed Algorithm
Now that procedural intervention in early glaucoma is becoming more broadly accepted, how should the treatment algorithm change?
| 5 min read | Opinion
Historically, glaucoma management has relied on controlling IOP with topical medications until surgery can no longer be deferred. This situation is changing – early intervention with devices such as iStent technologies is increasingly seen as safe and effective in mild-to-moderate patients. John Berdahl provides an example: “At a symposium of 150 optometrists, we asked how they would want their own eyes treated after a diagnosis of early glaucoma; 95 percent chose procedural intervention, not drops!” Clearly, a paradigm shift is underway, implying the need to reconsider patient management and treatment algorithms – but how?
Such a change might also encourage surgeons to schedule standalone MIGS procedures rather than just prescribing another eye-drop.
Nate Radcliffe asserts that managing patient psychology will be important. “Rather than simply providing patients with options, we should be confidently recommending early intervention,” he says. Berdahl agrees, and suggests ophthalmologists should do what is best for the patient, not necessarily what is easiest – and that may require changing old habits.
Which patients should qualify for early intervention? Ike Ahmed proposes that suitable patients include those on maximum tolerated medical therapy (MTMT) who need to reduce IOP but who are not bleb surgery candidates. “Other qualifying patients include individuals who are non-compliant, fluctuating, or progressing,” he says.
Similarly, Mark Gallardo suggests that most MTMT patients with high IOP qualify for angle-based MIGS. Berdahl concurs and adds, “Patients deserve stand-alone procedures if they can’t afford, tolerate or administer eye-drops – or if their glaucoma is progressing despite medication.” He adds that many cases meet those criteria, and notes that the safety of MIGS makes it suitable for first or second-line use. Similarly, Deborah Ristvedt believes iStent technologies are an attractive option for a range of patients, including those with ocular surface disease, fluctuating vision, hyperemia, medication side-effects, or compliance issues; those who have failed other procedures, such as SLT; and those on MTMT.
Paul Singh outlines three categories of patients he deems suitable for early intervention. “First: patients whose IOP can be controlled with medication, but who find compliance difficult; here, the goal is to reduce medication burden. Second: mild-to-moderate patients with high IOP despite heavy medication. In these cases, MIGS procedures can reduce IOP while potentially avoiding the need for riskier, more invasive surgery such as trabeculectomy in the future,” he says. “And third: medicated patients with IOP in the 20s and a target IOP in the low teens, who would not comply with additional eye-drops.”
Gallardo concisely sums up: “In general, I’d offer iStent technologies to any mild-to-moderate patient and any high-IOP patient on MTMT.”
In this context, Ahmed wonders if it is time to redefine important terms, such as MTMT and refractory glaucoma. “Are three or four eye-drops really that much better than one or two? Should we be more open to trying surgical routes before loading the eye with yet more medication?”
Gallardo agrees. “If topically-medicated patients have hyperemia, ocular discomfort, or foreign body sensation, we can call them refractory,” he says. “Basically, if they won’t use their medication, they have refractory glaucoma.” Sahar Bedrood also concurs, and suggests that the ophthalmology community should change its mindset and start recommending surgery after even only one or two drops, noting that it makes sense to intervene “while the TM tissue is actively pumping” to facilitate flow early in disease. Singh adds that the excellent MIGS safety record supports the rationale for relaxing the refractory glaucoma definition.
In conclusion, Ahmed shares a bold ambition: “We should upend the algorithm – apply interventional therapy in early disease, and prescribe medications later.” Looking ahead, Ahmed anticipates great potential in combining outflow procedures, such as iStent Infinite, with procedural pharmaceuticals, such as iDose®TR – “Such game-changing combinations would hugely defer the need for topical medication.” In any case, Ahmed says it is clear that the continued demonstration that early intervention gives better outcomes and quality of life will demand radical changes in the treatment algorithm. At this point in the ongoing paradigm shift, however, Ahmed believes we must start by offering stand-alone MIGS procedures to specific glaucoma patients – in particular, those whose IOP is not controlled by medication, but who do not need trabeculectomy or bleb surgery. If early intervention with MIGS can give these patients effective 24-hour IOP control with tolerable levels of medication, says Ahmed, it would be a success; “In brief, we must grasp the opportunity provided in early glaucoma to fundamentally alter the course of the disease – and the patient experience.”
