Did I Miss the MIGS Boat?

Combined cataract surgery with microinvasive glaucoma surgery (MIGS) is now considered the standard of care in glaucoma patients undergoing cataract surgery to aid in stability and topical therapy reduction. But what about those patients who missed the boat and are already pseudophakic? Can we go back in? Will insurance cover this? What is the best approach for pseudophakic patients whose glaucoma is uncontrolled with current treatment? A recent case highlights our algorithm, which is ever-changing based on new data and technology.

Case Study

A 74-year-old female patient was diagnosed with mild primary open-angle glaucoma in 2013 with a Tmax of 22/23, CCT in the 520s, and a family history of glaucoma. Our goal IOP of 18 or less was initially met with argon laser trabeculoplasty OU and continued with successful cataract surgery OU in 2016. In 2018, her IOP increased above the goal OU and was returned to goal with latanoprost qhs OU. Even with a goal IOP met in 2019, HVF and OCT progression was noted in both eyes, changing glaucoma severity to moderate-severe in the right eye. Also, significant typical PGA-related MGD and dry eye disease symptoms became a concern, including fluctuating vision. A lower goal IOP in the mid-teens was established. Additional medications improved the patient’s IOP to the mid-teens range, but she was very discouraged with increased ocular side effects. Additional laser was discussed, but there was concern regarding the effectiveness of SLT after ALT, and the patient would likely need to continue latanoprost. On the other hand, MIGS would have a higher likelihood of reaching the patient’s goal IOP and eliminating topical therapy, therefore reducing ocular side effects. The patient therefore opted for MIGS.

Our evolving MIGS algorithm considers:

• Combined with cataract surgery vs. stand-alone
• Glaucoma severity/stability
• Type of glaucoma
• Number of medications and tolerance
• Goal IOP
• Other ocular history (e.g., trauma, prior retina surgery)

For this patient, all MIGS were covered as stand-alone procedures under insurance except the iStent inject (Glaukos) and the Hydrus Microstent (Ivantis). We discussed revitalizing the natural outflow through the conventional (trabeculocanalicular) pathway before a subconjunctival procedure with mild to moderate primary open-angle glaucoma. With the recurring resistant nature of her IOP and the patient needing three treatments to reach her goal (ALT and 2 medications), OMNI Surgical System (Sight Sciences) 360° canaloplasty with inferior 180° goniotomy was recommended.

We started incorporating the OMNI device with our MIGS offerings last year, beginning with combined cataract surgery. However, we quickly discovered its relevancy in the pseudophakic space, as well as for patients who’d “missed the boat.” We have incorporated the OMNI in all stages of glaucoma, from ocular hypertension to severe glaucoma, even after other failed MIGS or subconjunctival procedures. To become a candidate for OMNI—and all angle-based procedures—it’s important to have a clear, open angle. The goal IOP with OMNI is typically in the mid-teens range.

The OMNI device addresses the three major resistance points, maximizing conventional aqueous outflow: unroofing trabecular meshwork, and dilating both Schlemm canal and distal collector channels. This implant and bleb-free procedure uses an ab-interno approach to combine up to 360° of both viscocanaloplasty and goniotomy to customize a treatment plan for each eye in one device. Recent data from the European Society of Cataract and Refractive Surgery (ESCRS) meeting found an average IOP lowering of 40% with OMNI¹ while still maintaining episcleral venous pressure back stop. Having a minimally invasive procedure that can reduce IOP and medication use is a win-win; also, if we’re seeing progression despite current medications and laser, OMNI could be a great option to delay the need to go to a subconjunctival procedure.

Postoperative Care: What to Expect in standalone cases?

The OMNI is performed through the same type of incision as cataract surgery, and it takes the same amount of time and anesthesia, as well as having a similar recovery. A stand-alone postoperative drop schedule is typically shorter, with 2 weeks of steroids, 1 week of antibiotic, and no NSAIDS typically needed. In some instances, initial reduction in vision may occur due to transient hyphema, which usually resolves within 1 to 2 weeks. However, the long-term benefit outweighs the temporary hyphema.

I stress to my patients that they should not be bending over or performing heavy lifting for at least a week. It’s possible to see an IOP spike at day 1 due to viscoelastic/hyphema or week 1 from steroid response. To surgeons comanaging OMNI, I recommend they consider opening a side-port incision in case the wound needs to be burped. We typically recommend continuing glaucoma drops for 1 month after surgery, even with a stable IOP, to minimize potential spikes. If the IOP is stable at 1 month, we stop drops and reassess the IOP in 2 weeks. Maximum IOP lowering effect typically occurs at the 6 to 8 week range.

In this case, the patient’s 1 day postoperative IOP was 11/18, and 1 week postoperative IOP was 14/15. A postoperative IOP of 15/16 continued at 1 and 2 months, all without glaucoma medication. A new baseline IOP was established at 6 to 8 weeks. No instance of hyphema has occurred at the time of this publication, and the patient reported her vision was back to normal at 1 week postoperative. The patient reports she is happiest about the significant reduction in redness and dryness, improved quality of vision, and elimination of glaucoma drop burden (Figure 1).

Additionally, we are happy to report that, no, glaucoma patients who’ve already had cataract surgery did not miss the boat on having a minimally invasive procedure to address their uncontrolled glaucoma. With a favorable safety and efficacy profile, OMNI is a great tool to have in your toolbox for pseudophakic patients with uncontrolled glaucoma.