The iStent is a Promising New Treatment for Glaucoma Patients that also Need Cataract Surgery
It is a promising era for glaucoma patients. On June 25, 2012, the Food & Drug Administration (FDA) approved the iStent Trabecular Micro-Bypass Stent System, Model GTS100R/L. The iStent is the first device ever approved to be used in conjunction with cataract surgery for adults with moderate open angle glaucoma.
What Causes High Intraocular Pressure in the Eye?
In typical open angle glaucoma, aqueous fluid is continually created in the epithelium (outer layers) of the ciliary body in the eye and then circulates through the anterior part of the eye. The aqueous fluid normally drains from the anterior chamber of the eye. This fluid flows out of the eye through a tissue meshwork called the trabecular meshwork that encircles the iris. After filtering through the trabecular meshwork the aqueous fluid exits the eye via Schlemm’s Canal, which flows into the bloodstream.
When the trabecular meshwork doesn’t function properly it slows the drainage and exit of the aqueous fluid so the pressure builds higher inside the eye. The higher intraocular pressure can damage the fibers of the optic nerve (glaucoma) and lead to vision loss.
iStent Increases the Outflow of Aqueous from the Eye and Lowers Eye Pressure
The iStent is an extremely small titanium tube about 1 mm in length with an opening of only 120 microns. It is so small that it is believed to be the smallest implant of any kind ever placed in the human body. The iStent is placed directly through the trabecular meshwork creating a tube-like opening for aqueous to flow into Schlemm’s Canal to help reduce intraocular pressure.
Worldwide Studies Prove the Effectiveness of the iStent
FDA studies proved the safety and effectiveness of the iStent. However, numerous other studies in Europe and Canada provide even more proof of its effectiveness. Discussions with a leading glaucoma specialist in Canada, who is very experienced with the iStent, reveal that using 2-3 iStents per eye is his procedure of choice for moderate glaucoma patients that also need cataract surgery. There is a moderately steep learning curve implanting the iStent and complications can occur because of that need to truly know how to implant the iStent. Therefore, it is advised to seek only a glaucoma specialist experienced with the iStent.
The iStent Trabecular Micro-Bypass Stent System is manufactured by Glaukos Corporation of Laguna Hills, Calif. The author has no financial interest in the iStent device or in the manufacturer of the device.