Minimally Invasive Glaucoma Surgery (MIGS)

Indications and Candidacy

In patients with mild-moderate glaucoma with an IOP that has been unable to be controlled by medications or who have poor medication compliance, a MIGS device appears to be a viable option. Clinical trials have shown there to be a significant decrease in IOP over periods of up to 24 months along with a significant decrease in medication usage. The procedure has maintained a high safety profile with minimal adverse effects. The device can provide a method of treatment for glaucoma patients that decreases reliance on medications without the safety risks of more invasive procedures. Patients that are candidates are: - Patients with mild-moderate glaucoma, primary open-angle glaucoma, pseudoexfoliation glaucoma, or pigmentary dispersion glaucoma - Glaucoma is uncontrolled with maximum pharmacologic treatment or there are barriers preventing adequate medication dosing - Age greater than 18 - Patients with clinically significant cataract, as surgery may be performed simultaneously. All patients should have a pre-op comprehensive eye exam including gonioscopy and a detailed medical history. Contraindications: Relative contraindications for this procedure may include angle-closure glaucoma, secondary glaucoma, advanced glaucoma, previous glaucoma surgery, or severely uncontrolled IOP.

Day of Surgery:

Cataract extraction and IOL implantation occur first. The head is properly positioned to perform an adequate view of the angle anatomy with a gonio lens. A corneal incision is made and the anterior chamber is filled with viscoelastic. The inserter is advanced across the anterior chamber and, with the magnified view of a gonioprism, the device is then implanted through the trabecular meshwork and secured into Schlemm’s canal. There is typically an egress of heme from Schlemm’s canal, indicating proper placement. At the end of the surgery, the corneal wounds are hydrated for a watertight seal as would be performed in cataract surgery alone; typically, no sutures are necessary.

CLICK HERE the watch a video of a MIGS procedure.

Complications

Placing a foreign object into the eye does introduce the potential risk of intraoperative complications, e.g., if the device is malpositioned and the tip becomes occluded by iris or if the device becomes dislodged. Postoperatively, there can be IOP spikes and hyphema. Also, because it is a fairly new procedure, it is considered experimental and not currently covered by many commercial insurances, although it does have excellent Medicare coverage. Preoperatively, candidates require a full glaucoma and cataract work up with ancillary testing (pachymetry, visual field, RNFL analysis, K readings, axial length, etc.). Blood thinners should be stopped preoperatively if possible. Post-op care is the same as traditional cataract surgery. Patients should be informed that their vision may be blurred for the first few days due to the mild bleeding during the surgery.

MIGS has changed the way eye surgeons restore a patient's vision. The role of the optometrist in the comanagement of MIGS will only increase as more devices are introduced to the market and more patients undergo MIGS procedures. Click on the article below to learn more.

MIGS Patient Journey: Ultimate Guide for the New Practitioner