Glaucoma resulting in optic nerve damage and vision loss, and may be mild or severe. It can be due to an eye injury, inflammation, a tumor, or advanced cases of cataracts or diabetes. It can also be caused by certain drugs such as steroids. Treatment depends on whether it is open-angle or angle-closure glaucoma. In pseudoexfoliation glaucoma (also, "PEX", "exfoliation glaucoma") the pressure is due to the accumulation of microscopic granular protein fibers, which can block normal drainage of the aqueous humor. PEX is prevalent in Scandinavia, primarily in those over 70, and more commonly in women. Pigmentary glaucoma (also, pigmentary
Glaucoma valve drainage, such as iStent, CyPass, or Hydrus. A Cochrane Review of various aqueous shunts and modifications found that the Baerveldt implant may result in lower IOP than the Ahmed implant, but it was unclear if the difference in IOP reduction was clinically significant. The review suggests that practitioners should operate with the devices that they are most comfortable with, and have the most experience using. The glaucoma valve implant is indicated for glaucoma patients not responding to maximal medical therapy, with previous failed guarded filtering surgery (trabeculectomy) or in cases where conventional drainage surgery is unlikely to succeed. Common situations