A cataract is cloudiness of the lens in the eye, causing blurred vision. Typically, cataracts affect both eyes, but usually one eye is more severely affected. In most cases, cataracts are a result of normal aging; most people over about 65 have some cataract formation.
However, they may also sometimes be present from birth or may be due to factors such as eye injury, certain eye diseases such as uveitis (inflammation of various internal eye structures), prolonged exposure to sunlight, long-term corticosteroid treatment, or diabetes. Cataracts are also common in people with Down syndrome.
Smoking increases the risk of developing cataracts. Typically, cataracts develop over months or years.
They cause only visual symptoms, such as blurred vision, altered color vision, and seeing haloes around bright lights.
Treatment is with surgery to remove the natural lens and, in most cases, replace it with an artificial one. This usually improves vision significantly, although some people still need to wear glasses or contact lenses afterward

Othere related diseases

BAROTRAUMA
Barotrauma is damage or pain, mainly affecting the middle ear, caused by changes in pressure.
Such changes are common when flying or diving, and may cause...

BLEPHARITIS
Blepharitis is inflammation of the eyelids, causing redness and itchiness, greasy scales at the lid margins, and crusts on the eyelashes.
It may be associ...

CATARACT
A cataract is cloudiness of the lens in the eye, causing blurred vision. Typically, cataracts affect both eyes, but usually one eye is more severely affected. I...

CHALAZION
A chalazion is a round, red, usually painful swelling in the upper or lower eyelid caused by blockage of one of the meibomian glands (oil-secreting glands that ...

CONJUNCTIVITIS
Conjunctivitis is inflammation of the conjunctiva (the clear membrane covering the white of the eye), causing redness— hence its common name “red eye”— ...

EARWAX
Also called cerumen, earwax is produced by glands in the outer ear canal to clean and moisten the canal. Normally, the wax emerges naturally, but sometimes it b...

ECTROPION AND ENTROPION
Ectropion is a turning outward of the lower eyelid. The eyelid’s exposed inner surface becomes dry and sore, and the eye may water continuously. Because the e...

EUSTACHIAN TUBE DYSFUNCTION
The Eustachian tube, running from the middle ear to the back of the nose, acts as a drainage tube and also regulates pressure in the middle ear. In Eustachian t...