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# Revised Safety Alert on Alcon’s CyPass Micro-Stent
- URL: https://www.fdaweb.com/revised-safety-alert-on-alcons-cypass-micro-stent/
- Published: 2018-10-25T12:00:00.000Z
- Updated: 2026-09-15T00:40:33.000Z
- Author: David McFarland
- Tags: Devices, #legacy-id-D5142674

FDA has issued a [revised safety alert](http://FDA has issued a revised safety alert %28XXINSERT LINKX on Alcon’s CyPass Micro-Stent, a small tube with tiny holes that is surgically implanted in the eye, due to its risk of eye damage. The device is used to drain fluid that causes high eye pressure and vision loss in people with glaucoma. In 2016, it %28XXX SUBSTITUTE XXX%29was approved for use during cataract surgery to reduce eye pressure in adults with the most common type of glaucoma, open-angle glaucoma.     The agency says that patients who have the device implanted are at risk of losing cells in the protective outer layer of the eye %28cornea%29. “Endothelial cells line the inner surface of the eye's cornea and are important in keeping vision clear,” it says. “These cells do not regrow after they are damaged. Endothelial cell loss may be associated with damage to the cornea including swelling, cloudiness, eye pain, reduction in vision, and the potential need for corneal transplant.”     The revised alert also provides post-approval study data that has been reviewed and confirm the earlier concerns. Key findings include:      At five-year follow-up, 27.2 % %2844/162%29 of implanted patients had more than 30% loss in endothelial cell density.     Data suggests a correlation between the amount the CyPass device extends into the anterior chamber of the eye, assessed by the number of visible retention rings on the device, and the rate of endothelial cell loss. ) on Alcon’s CyPass Micro-Stent, a small tube with tiny holes that is surgically implanted in the eye, due to its risk of eye damage. The device is used to drain fluid that causes high eye pressure and vision loss in people with glaucoma. In 2016, it was approved for use during cataract surgery to reduce eye pressure in adults with the most common type of glaucoma, open-angle glaucoma.

The agency says that patients who have the device implanted are at risk of losing cells in the protective outer layer of the eye (cornea). “Endothelial cells line the inner surface of the eye's cornea and are important in keeping vision clear,” it says. “These cells do not regrow after they are damaged. Endothelial cell loss may be associated with damage to the cornea including swelling, cloudiness, eye pain, reduction in vision, and the potential need for corneal transplant.”

The revised alert also provides post-approval study data that has been reviewed and confirm the earlier concerns. Key findings include:

- At five-year follow-up, 27.2 % (44/162) of implanted patients had more than 30% loss in endothelial cell density.
- Data suggests a correlation between the amount the CyPass device extends into the anterior chamber of the eye, assessed by the number of visible retention rings on the device, and the rate of endothelial cell loss.