Subconjunctival Implants [InnFocus MicroShunt® & Xen 45 Gel Stent]. Part 11 of 12 of “What’s New In Glaucoma Surgery” Presentation, a continuing education course for Optometrists presented by Patient-Focused Ophthalmologist, Dr. David Richardson on May 20, 2015.
These are implants that are designed to restrict the flow from the anterior chamber, through the sclera, under the conjunctiva, just as Trabeculectomy would. So instead of creating a flap and then trying to tie it down, just right, so you get some percolation fluid. These are actually design to restrict flow so that you get enough flow that the pressure is lowered but not so much that you have problems with Hypotony. But they are essentially modified Trabeculectomy. It’s just not, necessarily, making the same types of incisions.
Now, the InnFocus MicroShunt® — I’ve received a lot of press recently because some early results came out that look good but this does currently require an external incision, cutting through the conjunctiva, cutting down, creating a small flap in the sclera much smaller than you would for Trabeculectomy but it still Trabeculectomy. Still you would expect that you’re still going to need to use antimetabolites such as Mitomycin-C or 5-FU for it to work. Blood disperse, it disperse.
Xen 45 Gel Stent
This one here, though, is pretty neat. If you want something that’s going to give you flow through into the Subconjunctival space, I think the Xen 45 Gel Stent is pretty neat. We’ll take a look at this video here. You can see it’s this little this is little implant right here. you take this needle through the anterior chamber, you’re passing it into the Subconjunctival space and what you’re going to do is inject this gel stent and it’s going to create essentially flow from the Subconjunctival space into the — over the sclera, underneath the conjunctiva and the neat thing about this stent is they spent a lot of time engineering and designing it to make sure that this stent would maintain enough stiffness to keep this space open but have enough flexibility so that when it hit the that Subconjunctival space it would just kind of rotate down along the natural curvature of the sclera and not poke through the conjunctiva. But again this is is something that most likely will require some kind of help keeping that bleb open. For that reason I’m not as excited about the gel stent as I am with any procedure that does not require a bleb or antimetabolites. This is essentially what we call an Ab-Interno Trabeculectomy. It’s not really a Trabeculectomy because you’re not removing the trabecular tissue but the idea is the same- you’re creating a fistula. So far the IOP reduction looks pretty good at 12 month. It’s 31-42% but compare it back to what I showed with Canaloplasty it’s in the same range Canaloplasty doesn’t require a bleb.
What's New In Glaucoma Surgery Series:
- What’s New In Glaucoma Surgery
- Laser Trabeculoplasty ALT, SLT, MLT for Glaucoma
- Trabeculectomy Glaucoma Surgery
- Glaucoma Drainage Devices
- Cyclophotocoagulation and Trabectome for Glaucoma
- Glaukos iStent: A Quick Review and Commentary
- Canaloplasty Minimally Invasive Glaucoma Surgery
- Promising, Pending FDA Glaucoma Surgical Treatments
- Trabecular Microbypass, Hydrus™ Microstent
- Suprachoroidal Implants [SOLX®, STARflo™, iStent Supra®, CyPass®
- Subconjunctival Implants [InnFocus MicroShunt® & Xen 45 Gel Stent]
- Ab-Interno Canaloplasty: The Most Promising, FDA-Approved, Glaucoma Surgical Treatment?