#12: Minimally Invasive Glaucoma Surgery Devices

Traditionally, open-angle glaucoma has been treated medically with therapies that aided in decreasing aqueous humor production or increasing aqueous humor outflow. Because of the high risks associated with surgery, invasive procedures were often seen as a last resort and only for patients with advanced glaucoma who required multiple medications to control their intraocular pressure.

The advent of minimally invasive glaucoma surgery (MIGS) devices, however, has transformed the care of patients with mild-to-moderate glaucoma thanks to their much improved safety profile and more rapid recovery time compared to more invasive techniques. Clinical trials have shown a significant decrease in IOP over periods of up to 24 months along with a significant decrease in medication usage following MIGS.

The Trabectome was the first MIGS device to be introduced, approved by the U.S. Food and Drug Administration (FDA) in 2004. It was followed by the iStent® Trabecular Micro-Bypass Stent in 2012. In July 2016, the CyPass® micro-stent received FDA approval. The XEN Gel Stent received CE Mark approval in Europe in 2011 but is still awaiting approval in the United States. Several other devices – including the Hydrus® micro-stent and the InnFocus Microshunt™– are currently in clinical trials around the world.

Minimally invasive glaucoma surgery devices have transformed the care of patients with mild-to-moderate glaucoma.Based upon numerous clinical trials and thousands of patient cases, physicians consider the following groups as current candidates for MIGS:

• Patients with mild-to-moderate glaucoma

• Patients with primary open-angle glaucoma, pseudoexfoliation glaucoma, or pigmentary dispersion glaucoma

• Patients with uncontrolled glaucoma despite maximum pharmacologic treatment or the presence of barriers preventing adequate medication dosing

• Patients older than 18 years of age

• Patients with clinically significant cataract (for simultaneous surgeries)

There are numerous efforts underway to improve the efficacy of current MIGS devices and potentially expand its use. Combining surgical procedures, as is currently done with MIGS and cataract procedures, is being explored. Appropriate use of preoperative and intraoperative imaging is also being studied to help enhance the surgical technique.