With all the news surrounding minimally invasive glaucoma surgery (MIGS) reimbursement recently, it seems that the most common question that I get asked is, “Have these changes altered your MIGS choice/algorithm?” As a glaucoma specialist, my answer is always emphatically and unequivocally, “No.”

Glaucoma is the second leading cause of blindness in this country;¹ it is irreversible and incurable. We, as ophthalmologists, must utilize every tool available to us to help our patients fight this blinding disease. The combination of an aging population and longer life spans make winning this struggle even more critical.

For a long time, the only incisional glaucoma surgical option we had was filtering surgery. While very effective at lowering IOP, filtering surgery has many well-known and well-described complications both postoperatively and lifelong.

Thankfully, with the advent of MIGS, we have another category of glaucoma surgeries that are effective but with a more favorable safety profile.² The MIGS space has grown so much that we now have many different MIGS procedures and devices to choose from.² With this growth, there has also been notable changes in reimbursement. The most publicized of these were the changes to the CPT coding and payment for iStent inject (Glaukos) and Hydrus Microstent (Alcon), as well as insurance denials and alterations in payment for certain other procedures such as canaloplasty and goniotomy.

While these recent reimbursement changes do present a challenge, I will explain here why my choice of MIGS has not changed.

MIGS: THE GAME CHANGER

A growing body of data

The acceptance of MIGS as a viable and important treatment option for glaucoma is evident with its inclusion as a separate incisional glaucoma surgery category in the AAO 2020 Primary Open Angle Glaucoma Preferred Practice Pattern.³ This is further emphasized when we look at the rates of trabeculectomy and tube shunt surgery based on Medicare claims and payment data between 1994 and 2017. We see a significant decrease in the number of both trabeculectomy and tube shunt surgeries during that period despite an increase in the overall number of people with glaucoma.⁴

As physicians, we strive to practice evidence-based medicine to provide the best care for our patients. Some of the strongest MIGS data to date came from the HORIZON Trial, which demonstrated that patients who underwent cataract surgery with a Hydrus Microstent were more likely to be medication-free and less likely to require additional incisional glaucoma surgery at 5 years compared to those who just had cataract surgery alone.⁵

Both those data points are very important to me as a glaucoma specialist. Potentially more time medication free and less time with a filtering surgery provides a better outcome and quality of life for our patients.

The goniotomy option

Another MIGS with significant long-term evidence is goniotomy, which was described by Barkan in 1938.⁶ With the advent of multiple goniotomy devices such as the Kahook Dual Blade (New World Medical), Streamline (New World Medical), iAccess (Glaukos), Trabectome (MST), TrabEx (MST), OMNI (Sight Sciences) and SION (Sight Sciences), the number of papers and scientific papers supporting goniotomy’s efficacy and safety has grown.

On a physiologic level, goniotomy makes sense for many disease processes where the trabecular meshwork is the site of pathology and its removal would be beneficial. These include steroid-induced glaucoma, pseudoexfoliation glaucoma, pigmentary glaucoma and chronic angle-closure glaucoma. Goniotomy has proven safe and effective for treatment of severe and refractory glaucoma⁷ and can be done as a standalone procedure or in combination with cataract surgery.

Continued innovation

Just recently, the iStent Infinite (Glaukos) received FDA 510k clearance for its standalone MIGS procedure. The device can provide a treatment alternative for a wide range of glaucoma stages with a favorable safety profile.

THE MOST SIGNIFICANT CHALLENGE

Narrow reimbursement criteria

Overall, my choice in MIGS procedure is guided by evidence and what is best for the patient, and that has not changed in any way because of reimbursement.

Still, insurance approval for MIGS has proven to be the toughest barrier to being able to perform a procedure. For example, both iStent inject and Hydrus Microstent are only approved to be done at the same time of cataract surgery in patients with primary open-angle glaucoma, mild or moderate stage. If the patient is not having concomitant cataract surgery or has a different stage or type of glaucoma, the procedure would not be approved by the carrier, even though it would likely be beneficial to the patient.

Prepare to document — and appeal

In addition, insurance carriers have from time to time provided barriers to approving goniotomy despite the mountain of significant long-term evidence supporting the efficacy, safety and benefits of goniotomy to our patients. With all new procedures like the iStent Infinite, slow adoption among insurance carriers is the biggest among all the challenges we face, despite the benefits these new technologies can provide to the patients. I personally have spent countless hours on appeals letters and peer-to-peer calls to try to get approval for certain MIGS for my patients.

In my experience, the most important step in obtaining approval is critical documentation discussing the medical necessity of the MIGS and why the alternative treatment options would not be as favorable for the patient based on potential risks and benefits. Yet despite these efforts, there were times where the approvals and appeals were denied and I have had to accept the financial loss for a non-covered MIGS. I can at least take solace in the fact that I still felt I did what was best for the patient by performing that MIGS.

In the end, we are the greatest advocates for our patients, and while these barriers do exist, we should try to provide the best possible care for our patients to help fight this blinding disease. OM

REFERENCES

1. Rossi T, Romano MR, Iannetta D, et al. Cataract surgery practice patterns worldwide: a survey. BMJ Open Ophthalmol. 2021;6(1):e000464. Published Jan. 13, 2021.
2. Congdon N, O’Colmain B, Klaver CC, et al. Eye diseases Prevalence Research Group. Causes and prevalence of visual impairment among adults in the United States. Arch Ophthalmol. 2004;122(4):477-485.
3. American Academy of Ophthalmology. Primary Open Angle Glaucoma Preferred Practice Pattern Glaucoma. https://www.aaojournal.org/article/S0161-6420(20)31024-1/fulltext
4. Boland MV, Corcoran KJ, Lee AY. Changes in Performance of Glaucoma Surgeries 1994 through 2017 Based on Claims and Payment Data for United States Medicare Beneficiaries. Ophthalmol Glaucoma. 2021;4(5):463-471.
5. Ahmed IIK, De Francesco T, Rhee D, et al. HORIZON Investigators. Long-term Outcomes from the HORIZON Randomized Trial for a Schlemm’s Canal Microstent in Combination Cataract and Glaucoma Surgery. Ophthalmology. 2022;129(7):742-751.
6. Barkan O. Technic of Goniotomy. Arch Ophthalmol. 1938;19:217-223.
7. Salinas L, Chaudhary A, Berdahl JP, et al. Goniotomy Using the Kahook Dual Blade in Severe and Refractory Glaucoma: 6-month Outcomes. J Glaucoma. 2018;27(10):849-855.

Bac Nguyen, MD, is a glaucoma and cataract surgeon at Berkeley Eye Center in Houston, Texas. He is passionate about patient care, clinical research and education. He serves as a site principal investigator for several FDA studies, with his primary research focus on the advancement of medical and surgical innovations in glaucoma. Disclosures: Dr. Nguyen reports financial relationships with Aerie Pharmaceuticals, Allergan, Bausch + Lomb, Glaukos, iStar Medical, New World Medical, Tarsus Pharmaceuticals and Visus Therapeutics.