My MIGS of Choice, with Robert A. Van der Vaart
The benefits of incorporating MIGS into your comprehensive practice, and my go-to MIGS device: XEN
Comprehensive ophthalmologists have helped shape a new glaucoma treatment model by incorporating MIGS. The threshold for shifting from management to surgical referral for MIGS is far lower and more individualized than it was in the past, when trabeculectomy and drainage procedures were the only surgical options. MIGS devices have also broadened the scope of personnel able to provide glaucoma treatment, expanding beyond subspecialists to include cataract surgeons and also those of us who provide comprehensive care.
A strong demand for MIGS procedures in my region has resulted in me flipping my case mix to 75 and 25 percent surgical and medical, respectively. Although the exact proportion for each practitioner will vary, MIGS technologies present an opportunity to control that mix while offering patients with glaucoma a broad range of options beyond medications.
One of the strongest arguments for comprehensive surgeons to use MIGS devices is that it leads to new referrals, which can be great in number. In my small- to mid-sized community of about 200,000 people, two fellowship-trained glaucoma surgeons are booked all the time. As word got out that I offered MIGS and some filtration procedures, my surgical practice grew exponentially. I even have more general cataract referrals because of the rapport I’ve built with doctors referring to their glaucoma patients.
In my experience, MIGS are not difficult to learn or fit into the schedule of a comprehensive practice. As a result, I think we’ll see more comprehensive ophthalmologists implement MIGS within their own practices.
Choosing which MIGS device to offer
At this point, MIGS technologies are so well established that virtually every surgeon offers at least one procedure performed concurrently with cataract surgery. These MIGS offer the opportunity to improve chronic disease while we’re already in the eye, without additional risk, and rely on the same basic skills.
For me, it’s important that I also offer other MIGS options, including standalone procedures that allow me to treat pseudophakic patients and those who don’t need cataract surgery yet. The XEN Gel Stent, the only subconjunctival option, can be used alone or during cataract surgery for patients with refractory open-angle glaucoma. XEN has revolutionized how I care for more advanced cases where patients are refractory to medications and may have already had other glaucoma surgery. Instead of moving to trabeculectomy, I can do this 15-minute procedure with similar recovery to cataract and no negative effect on vision (1). Additionally, both viscodilation and goniotomy procedures are also approved for standalone use.
The learning curve for standalone MIGS is about the same as that for MIGS we use concurrently with cataract surgery. I also do several standalone in-office glaucoma procedures, including selective laser trabeculoplasty (SLT), YAG peripheral iridotomy for narrow angles, and placement of the bimatoprost intracameral implant.
How I schedule MIGS and follow-up care
MIGS procedures are not lengthy, so their incorporation into a schedule is relatively straightforward. In the surgery center, I schedule three time slots:standard cataract surgery, cataract with MIGS, and standalone MIGS, for which I allocate 20, 25 and 15 minutes respectively.
All MIGS have similar scrub tech setups, with small variations. We use the same techniques and materials, and the differences are small enough to make for an easy flow. As a result, I’m very comfortable performing different procedures successively rather than blocking time. In-office scheduling involves both surgical follow-up and office-based procedures. My follow-up schedule is the same for all MIGS, with the first two visits occurring at one day and one week, and a third visit based on the one-week status, ranging from three weeks to two months. We keep some slots open as a contingency, in case someone needs an extra follow-up visit, revision or bleb needling for XEN, or an urgent in-office laser procedure.
To handle in-office glaucoma procedures efficiently, we block out two mornings per month. Both our techs and patients are happy with this approach because there’s no waiting. Everything moves along very quickly and smoothly when techs are doing the same thing, rather than interrupting regular clinic days with prep and consent forms. They get patients checked in, consented, and prepared with drops or Betadine, and then patients receive treatment.
Case studies: moderate and advanced glaucoma
My MIGS recommendation comes from my 85 percent success rate of getting patients to their pressure goal. This goal depends on the history and stage of the disease. Sometimes the goal is to reach the target pressure with no medications, while in advanced cases the goal may be to lower pressure enough to control it with just one drop. One of our advanced glaucoma patients, an 85-year-old woman, had visual field loss and fixation in both eyes. She had undergone bilateral trabeculectomy and revision in one eye, but neither bleb was functioning. With four medications through three drops (one was a combination), her pressure was 16-18 mm Hg in both eyes.
I implanted XEN bilaterally in 2020, approximately one month apart, with the aim of getting the patient down to one medication. Two years later, her pressures have remained 9-11 mm Hg on no drops. This overwhelmingly positive result is rare in advanced cases, but even controlling the patient on one drop would have been a success. Without XEN, she would have needed a tube shunt, which requires significant postoperative healing. However, with her MIGS procedure, she returned to baseline vision and activities within a week, and was incredibly happy with the results.
In another case, a 68-year-old man with mild glaucoma showed early thinning in both eyes on OCT. He’d been at target on drops for five years and had pressures of 15 mm Hg. Despite trying three different classes of drugs, he continued to have severe red eyes. The patient was retired and enjoyed socializing, but hated the way his eyes looked. Previous SLT had not worked, so he was referred to me to eliminate drops.
I used XEN on the first eye, and he was off drops at day one. At one month, the redness had disappeared and he was beating down the door asking me to operate on his other eye! He was ecstatic about controlling his disease without feeling anxious about his looks. Four years later, his pressures are in the 13-16 mm Hg range on no medications.
By reducing or eliminating topical medications, MIGS devices also diminish the impact of shaky compliance on glaucoma management. Additionally, with no drops, patients don’t have to deal with detrimental effects on the ocular surface. In these two cases, the patients were thrilled that a MIGS device could get them off drops. As always, I was pleased to help them get the results they need to preserve their vision and quality of life.
- M Lenzhofer, et al., “Change in visual acuity 12 and 24 months after transscleral ab interno glaucoma gel stent implantation with adjunctive Mitomycin C,” Graefes Arch Clin Exp Ophthalmol, 257, 2707 (2019). PMID: 31494710.
Comprehensive ophthalmologist and cataract and glaucoma surgeon at Wilmington Eye in Wilmington, North Carolina, USA.