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
Supernumerary body part considered to have lost much or all of their original function through evolution. These body parts can be classed as additional to the required functioning of the body. In human anatomy the vermiform appendix is sometimes classed as a vestigial remnant. Prosthesis is an artificial extension that replaces a body part, and cybernetics is the study of computer technology in relation to organisms which can include replacement or additional body parts. Body integrity identity disorder (BIID) is a psychiatric disorder in which a person thinks that they have one or more additional limbs than they should, despite having two arms