Fact Sheet: Aging Vision and Cataracts

Eye Anatomy: How We See

• The human eye has two structures that work together to focus light onto the retina. The outer focusing structure is called the cornea. The inner focusing structure is called the crystalline lens.
• Light rays pass first through the cornea and then through the crystalline lens. The cornea and crystalline lens focus incoming light by bending all the light rays to meet at a single point on the retina. These images are then transferred via the optic nerve to the brain where we “see” them.

Cataracts

• A cataract occurs, usually gradually, as the natural lens of the eye becomes clouded or discolored.
• This clouding of the natural lens of the eye causes light entering the eye to scatter prior to reaching the retina. This causes hazy or blurred vision (see image at right).
• If left untreated, cataracts can cause blindness.
• Cataracts are treated by removing the clouded natural lens   of the eye and replacing the natural lens with an intraocular lens (IOL) implant.
• According to the Eye Surgery Education Council, “About 60 percent of those older than 60 years and 70 percent of those older than 75 years have cataracts.”¹
• The Eye Disease Prevalence Research Group reported in Archives of Ophthalmology that an estimated 20.5 million Americans older than age 40 have a cataract in either eye and the total number of persons who have a cataract is estimated to rise to 30.1 million by 2020.²
• Approximately 3 million cataract surgery procedures are performed in the United States and 15 million performed worldwide³ every year to restore vision loss due to cataracts, making it the most commonly performed surgical procedure according to the Eye Surgery Education Council.

References

1. Eye Surgery Education Council. Available at: http://www.eyesurgeryeducation.com/Cataract_Treatment.html. Accessed on November 19, 2009.
2. Congdon N, Vingerling JR, Klein BE, et al; Eye Diseases Research Group. Prevalence of cataract and pseudophakia/aphakia among adults in the United States. Arch Ophthalmol. 2004;122(4):487-94.
3. Market Scope. 2008 Annual Cataract Surgeon Survey. St. Louis, Mo: Market Scope LLC.