Minimally Invasive Glaucoma Surgery (MIGS)

In the past decade, glaucoma surgery has undergone significant advancements with the emergence of Minimally Invasive Glaucoma Surgery (MIGS). MIGS techniques have become widely adopted due to their safer profile compared to traditional glaucoma surgeries (trabeculectomy and tube shunt surgery) and their considerably quicker recovery times. Some MIGS procedures are performed in conjunction with cataract surgery, while others can be carried out as standalone treatments. All MIGS procedures focus on enhancing fluid outflow from the eye to reduce intraocular pressure. Below is a summary of MIGS options available:

Goniotomy

Goniotomy involves removing a portion of the malfunctioning internal drain (trabecular meshwork) of the eye in order to restore the function of the eye’s natural drainage system. The Kahook Dual Blade is designed for clean removal of the trabecular meshwork with minimal damage to surrounding tissues. There are no implants with this procedure and it can be safely combined with cataract surgery.

Viscodilation +/- Trabeculotomy

Another minimally invasive, implant-free technique for reducing eye pressure involves using specialized surgical devices to gently dilate and restore the eye’s natural drainage system to enhance fluid outflow. This is performed using the iTrack Microcatheter, the OMNI Surgical System, and the Streamline Surgical System. Since external conjunctival tissues remain undisturbed, future surgical interventions, if needed, can be performed with greater success rates.

Additionally, the iTrack Microcatheter and OMNI Surgical System can be used to create an opening in the trabecular meshwork similar to a goniotomy, however they can be applied to more clock hours to achieve greater fluid flow and lower eye pressures.

Xen Gel Stent

The XEN Gel Stent is a surgical implant designed to lower eye pressure by filtering fluid from the inside of the eye to the outside of the eye. This tiny, flexible tube is implanted under the conjunctiva into the anterior chamber of the eye, and functions similarly to a traditional tube shunt but with a significantly slimmer profile.  

iStent Inject

The iStent lowers eye pressure by creating an opening in the trabecular meshwork to enhance fluid outflow. The iStent Trabecular Micro-Bypass is the smallest medical device ever approved by the FDA and can be safely inserted during cataract surgery. It stents open a portion of the trabecular meshwork to allow fluid to flow directly into the natural collector channels. It is imperceptible to the eye due to its small size and location.

Hydrus Microstent

Similar to the iStent, the Hydrus Microstent is implanted into the eye’s internal drainage canal during cataract surgery to improve fluid outflow. Once implanted, it helps drain fluid past the trabecular meshwork into the eye’s natural drainage system. The Hydrus Microstent is well-regarded for its safety and provides mild to moderate reductions in eye pressure while remaining undetectable to the eye after implantation.

Cyclophotocoagulation (CPC)

This is a specialized laser used to target and shrink the ciliary body, the structure in the eye just behind the iris which produces fluid. As a result, the eye produces less fluid and the eye pressure is reduced. Modern advances have allowed for lower laser energy and improved targeted treatment of the ciliary processes. The laser can be applied from the inside of the eye (endoscopic) or from the outside of the eye (trans-scleral).