Pub. date: 2008 | Online Pub. Date: April 21, 2008 | DOI: 10.4135/9781412963855 | Print ISBN: 9781412941860 | Online ISBN: 9781412963855| Publisher:SAGE Publications, Inc.About this encyclopedia
Cataract is the single leading cause of blindness worldwide. It is caused by the opacification (clouding) of the crystalline lens within the eye. Luckily, the disorder can usually be corrected by surgical removal of the clouded lens and, if possible, replacement of the old lens with a synthetic one in order to restore proper sight. Cataract can be classified by its cause, stage, or anatomical classification. While age-related cataract is most frequently observed, other common forms of cataract include congenital, traumatic, or complicated. Congenital cataracts are present from birth or develop very early in life, necessitating early removal of the clouded lens in order to allow for proper development of the infant's sensitive visual system. Eye trauma from accidents or injuries can also cause cataracts to form in the eye. Complicated cataracts develop when other eye diseases—such as glaucoma, retinitis pigmentosa, retinal detachment, or uveitis—affect the physiology of the lens. ...