A cataract is a clouding of the normally clear lens of your eye. For people who have cataracts, seeing through cloudy lenses is a bit like looking through a frosty or fogged-up window.

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.

Most cataracts develop slowly and don't disturb your eyesight early on. But with time, cataracts will eventually interfere with your vision.

At first, stronger lighting and eyeglasses can help you deal with cataracts. But if impaired vision interferes with your usual activities, you might need cataract surgery. Fortunately, cataract surgery is generally a safe, effective procedure.

Symptoms Causes Risk factors Prevention

Signs and symptoms of cataracts include:

  • Clouded, blurred or dim vision
  • Increasing difficulty with vision at night
  • Sensitivity to light and glare
  • Seeing "halos" around lights
  • Frequent changes in eyeglass or contact lens prescription
  • Fading or yellowing of colors
  • Double vision in a single eye

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 signs and symptoms you're more likely to notice.

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 blurriness, see your doctor right away.

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