A cataract is a clouding of the normally clear lens of the eye.Clouded vision caused by cataracts can make it more difficult to read, drive a car (especially at night) or see the expression on a friend's face.

- Increasing difficulty with vision at   night - Sensitivity to light and glare - Need for brighter light for reading - and other activities - Seeing "halos" around lights

Signs and Symptoms of cataracts include:

At first, the cloudiness in your vision caused by a cataract may affect only a small part of the eye's lens and you may be unaware of any vision loss. As the cataract grows larger, it clouds more of your lens and distorts the light passing through the lens. This may lead to more-noticeable symptoms.

When to see a doctor

Make an appointment for an eye exam if you notice any changes in your vision. If you develop sudden vision changes, such as double vision or flashes of light, sudden eye pain, or sudden headache, see your doctor right away.

Causes

Most cataracts develop when aging or injury changes the tissue that makes up the eye's lens. Some inherited genetic disorders that cause other health problems can increase your risk of cataracts.

Risk factors

- Excessive exposure to sunlight - Smoking - Obesity - High blood pressure - Previous eye injury or inflammation - Previous eye surgery