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• Summary
• Start Here
• Diagnosis and Tests
• Treatments and Therapies

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• Related Issues
• Genetics

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• Images
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Research

• Statistics and Research
• Clinical Trials
• Journal Articles

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Summary

A cataract is a clouding of the lens in your eye. It affects your vision. Cataracts are very common in older people. By age 80, more than half of all Americans either have a cataract or have had cataract surgery.

A cataract can occur in either or both eyes. It cannot spread from one eye to the other. Common symptoms are

• Blurry vision
• Colors that seem faded
• Glare - headlights, lamps or sunlight may seem too bright. You may also see a halo around lights.
• Not being able to see well at night
• Double vision
• Frequent prescription changes in your eye wear

Cataracts usually develop slowly. New glasses, brighter lighting, anti-glare sunglasses or magnifying lenses can help at first. Surgery is also an option. It involves removing the cloudy lens and replacing it with an artificial lens. Wearing sunglasses and a hat with a brim to block ultraviolet sunlight may help to delay cataracts.

NIH: National Eye Institute

Start Here

• Facts about Cataract (National Eye Institute) Also in Spanish
• What Are Cataracts? (American Academy of Ophthalmology) Also in Spanish

Diagnosis and Tests

• Dilating Eye Drops (American Association for Pediatric Ophthalmology and Strabismus)
• Preoperative Testing (American Academy of Ophthalmology)

Treatments and Therapies

• Cataract Surgery (American Academy of Ophthalmology) Also in Spanish
• Cataract surgery - slideshow (Medical Encyclopedia) Also in Spanish
• IOL Implants: Lens Replacement after Cataracts (Intraocular Lenses) (American Academy of Ophthalmology) Also in Spanish

Related Issues

• Facts and Myths about Cataracts (Prevent Blindness America) - PDF
• Intraocular Lens Dislocation (American Society of Retina Specialists)
• Retained Lens Fragments (American Society of Retina Specialists)

Genetics

• Autosomal dominant optic atrophy and cataract: MedlinePlus Genetics (National Library of Medicine)
• Hyperferritinemia-cataract syndrome: MedlinePlus Genetics (National Library of Medicine)

Images

• Cataract Vision Simulator (American Academy of Ophthalmology) Also in Spanish
• Cataracts (Logical Images)

Videos and Tutorials

• Cataract (Medical Encyclopedia) Also in Spanish

Statistics and Research

• Cataract Data and Statistics (National Eye Institute)

Clinical Trials

• ClinicalTrials.gov: Cataract (National Institutes of Health)
• ClinicalTrials.gov: Lenses, Intraocular (National Institutes of Health)

Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)

• Article: Association between MMP-2 gene polymorphism and cataract susceptibility: A protocol for...
• Article: MicroRNA-124 facilitates lens epithelial cell apoptosis by inhibiting SPRY2 and MMP-2.
• Article: OUR EXPERIENCE WITH ACTIVE SENTRY AND CENTURION OZIL HANDPIECES.
• Cataract -- see more articles

Reference Desk

• Glossary of Terms (Foundation of the American Academy of Ophthalmology)
• How the Eyes Work (National Eye Institute) Also in Spanish
• NEI for Kids: Glossary (National Eye Institute)

Find an Expert

• American Foundation for the Blind
• Finding an Eye Doctor (National Eye Institute) Also in Spanish
• National Eye Institute

Older Adults

• Aging and Health: Cataracts (AGS Foundation for Health in Aging)

Patient Handouts

• Cataract (Medical Encyclopedia) Also in Spanish
• Cataract removal (Medical Encyclopedia) Also in Spanish
• Slit-lamp exam (Medical Encyclopedia) Also in Spanish
• Standard ophthalmic exam (Medical Encyclopedia) Also in Spanish