What Is a Cataract?
A cataract is a clouding of the eye's natural lens, which sits behind the iris and focuses light onto the retina. As the lens turns cloudy, less light reaches the retina and vision becomes blurred, dim or hazy, a little like looking through a fogged-up window.

Common causes and risk factors include:

Ageing, the most common cause
Diabetes, especially when blood sugar is poorly controlled
Eye injury or trauma
Prolonged UV exposure without eye protection
Smoking and heavy alcohol use
Long-term steroid use
Common Symptoms of Cataract
Watch for these signs:

Cloudy, blurry or dim vision
Glare and difficulty with night driving
Sensitivity to bright light
Needing more light to read
Frequent changes in glasses prescription
Faded or yellowish colours
Double vision in one eye
A dilated exam and a slit lamp examination allow an ophthalmologist to confirm a cataract and judge how advanced it is.