MIGs - Treatment - Glaucoma Research Foundation

Minimally Invasive Glaucoma Surgery (MIGS) procedures have been developed in recent years to treat patients earlier and more safely than conventional surgery. As with all new procedures, multi-year follow-up studies are required to see which ones will remain useful long-term.

MIGS procedures include microsurgical instruments and devices and smaller incisions that manipulate the eye tissues less and therefore reduce the risk of complications. The increased safety of these surgeries is traded for reduced effectiveness.

MIGS procedures and devices may work in a number of ways. Some enhance fluid outflow within the eye’s drainage system, some carry fluid to the outside of the eye. Some types of MIGS procedures are to be done only with cataract surgery, whereas other MIGS procedures can be performed independent of cataract surgery.

Cataract surgery alone lowers pressure, and the combination of a MIGS surgery and cataract surgery can lower pressure more to help reduce the need for medication. Implanting a MIGS device adds a few minutes to cataract surgery.

The MIGS group of devices and surgeries are divided into categories according to how they work:

Miniaturized versions of trabeculectomy: In these procedures, tiny tubes are inserted into the eye to help drain fluid from inside the eye to underneath the outer membrane of the eye (conjunctiva). For example, the FDA cleared XEN Gel Stent and the PRESERFLO (formerly InnFocus) MicroShunt which is cleared outside the US.
Angle-based surgeries: In these procedures, specialized instruments and devices are used to modify the eye’s drainage canals (trabecular meshwork, Schlemm’s canal, and collector channels) and improve the drainage of fluid from the eye. These procedures involve cutting through the trabecular meshwork (e.g., Trabectome, Kahook Dual Blade, OMNI Surgical System), bypassing the trabecular meshwork by placing a stent in the Schlemm’s canal (e.g., iStent Inject, Hydrus Microstent), and expanding the Schlemm’s canal and collector channels with a gel (e.g., iTrack, OMNI Surgical System). Different angle-based MIGS procedures can be combined in various ways in order to increase drainage of fluid from the eye.

Placement Of Migs Devices

Conventional surgeries for glaucoma include trabeculectomy or aqueous shunts (see below). While they can be more effective at lowering eye pressure and preventing progression of glaucoma, they also have more potential complications.

Who is a good candidate for MIGS procedures?

For angle-based MIGS, the best candidates are those with mild to moderate primary open-angle glaucoma (POAG). Other candidates include those who have side effects to medical therapy, or those who have undergone other procedures and still have elevated eye pressures.

Who performs MIGs procedures?

Ophthalmologists, particularly glaucoma specialists, provide MIGS as part of a number of treatment options available to their patients.

How do MIGS procedures compare with traditional glaucoma surgery?

When compared to traditional glaucoma surgeries such as trabeculectomy and aqueous drainage devices, MIGS procedures have lower efficacy but an improved safety profile. For most patients with mild to moderate glaucoma, the MIGS procedures provide adequate IOP lowering while reducing the risk of the potentially severe complications associated with traditional glaucoma surgeries.

Video Transcript

Video Transcript

Constance Okeke: I was an early adopter of MIGS, or one could call it minimally invasive glaucoma surgery, or it’s also termed microinvasive glaucoma surgery. I was an early adopter because I saw that there was a need to help patients surgically, that was a safer approach. We have traditional glaucoma surgeries, and they can be very effective, but they can also be route with complications that are not the outcome that you want for your patient. With the MIGS devices, they offer a safer approach because the effectiveness of lowering the eye pressure is there. Oftentimes, patients can get off of one or maybe more medications, which can make their quality of life enhanced. A lot of these procedures are very easily coupled with cataract surgery, so you can have the option of improving your vision with cataract removal and then also having your glaucoma better controlled with the potential of getting off one or more of your medications. So there are many advantages for a glaucoma patient to consider the MIGS options.

Ike K. Ahmed: When MIGS came through and some of these devices came to being, my thought was, we need something that defines these devices beyond traditional surgery. Something that would help us as clinicians and help patients to understand the difference between these newer devices and perhaps some of the older traditional options. I felt that an acronym MIGS, minimally invasive glaucoma surgery, would be appropriate. I very quickly realized that, of course, in ophthalmology, we work at such a microscale that it would be more appropriate, perhaps, to coin the term microinvasive glaucoma surgery. Some of the devices we use are like one-tenth of a millimeter in size, one or two widths of our hair in terms of diameter, so it truly is microinvasive, and invasive isn’t just incision size. It’s basically minimal disruption to normal anatomy and function of the eye.

William J. Link: The impact that MIGS, as a category, is having and will have is that many hundreds of thousands, to-be millions, of patients are benefiting from this elegant new surgical therapeutic step.

L. Jay Katz: MIGS has introduced a number of operations now that are a bridge between medications and laser trabeculoplasty for open-end glaucoma and then bridging that gap, which we have for filtering surgery like trabeculectomy and tube shunts. There’s nothing in that void before, and it’s offered us the opportunity to have procedures that are effective in lowering intraocular pressure but with a very high safety margin.

Malik Y. Kahook: Traditionally, MIGS has been focused on the mild to moderate glaucoma combined with cataract surgery. What you’re seeing right now is a big explosion in the research that’s being done for stand-alone procedures.

Thomas W. Burns: I believe that an injectable surgical alternative can change the paradigm. I further believe that the combination of restoring physiologic outflow within the eye and using pharmaceutical mechanisms in a combined or co-management basis, what I call cocktail therapy, will be the standard of care in the future.

Malik Y. Kahook: We’re all striving to get to the best possible outcome. That takes time, that takes dedication, it takes research, and most of all, it takes innovation, translational research, finding out what works in the laboratory, taking it into early studies, and then hopefully bringing it to market so as many people can benefit as possible.

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Thank you to Regine Pappas, MD for contributing to this article.

Regine Pappas, Md

Regine Pappas, MD

Dr. Regine Pappas is a Board-certified ophthalmologist, eye surgeon, and Fellowship-trained glaucoma specialist at Pinnacle Eye Center in Melbourne, Florida.