Cataracts are cloudy areas in the lens of your eye. Your lens is behind the coloured part of your eye (iris). Its job is to focus light onto the back of your eye. In some people, cataracts prevent light from reaching the back of the eye. This can cause vision problems.

Cataract surgery helps you see better. It replaces your natural lens, which has become cloudy, with a clear artificial one.

There are several types of cataract surgery. They include:

• Phacoemulsification. This is the most common type. The doctor makes a small cut (incision) in your eye. A special ultrasound tool is used to break your cloudy lens apart. Then the small pieces of the lens are removed and replaced with an artificial lens. Most people do not need stitches because the incision is so small.
• Extracapsular extraction. This uses a larger incision to remove the lens in one piece. It is replaced with an artificial lens. And the cut is stitched.
• Femtosecond laser-assisted cataract surgery (FLACS). This uses laser technology and replaces the natural lens with an artificial lens.

Cataract surgery is successful for most adults. Surgery may also improve vision in infants who have cataracts.

Both phacoemulsification cataract surgery and femtosecond laser-assisted cataract surgery (FLACS) work about equally well for treating cataracts in adults. FLACS may not be completely covered by provincial health plans, but it may be a better option in some cases. For example, people who are going to have multifocal lenses placed may choose FLACS.

People who have surgery for cataracts usually have:

• Improved vision.
• Increased mobility and independence.
• Relief from the fear of going blind.

Although the risk is low, surgery for cataracts does involve the risk of partial to total vision loss if the surgery is not successful or if there are complications. Some complications can be treated and vision loss reversed, but others cannot. Complications that may occur with cataract surgery include:

• A torn lens covering (posterior capsule rupture).
• Infection in the eye (endophthalmitis).
• Swelling and fluid in the centre of the nerve layer (cystoid macular edema).
• Swelling of the clear covering of the eye (corneal edema).
• Bleeding in the front of the eye (hyphema).
• Detachment of the nerve layer at the back of the eye (retinal detachment).

Complications that may occur some time after surgery include:

• Problems with glare.
• Clouding of the back portion of the lens covering (capsule) that remains after surgery. (Your doctor can easily treat this using a laser.)
• Glaucoma.
• Retinal detachment.
• Astigmatism or strabismus.
• Sagging of the upper eyelid (ptosis).

Usually, a cataract that isn't removed will slowly get worse and make your eyesight worse:

• You may no longer be able to do your usual daily activities.
• You may not be able to drive safely, especially at night.
• You may be more likely to fall or hurt yourself.

The cataract may make it hard for your doctor to check for other eye problems, such as damage from diabetes.

When a cataract isn't treated until after it has become severe, the surgery may be harder to do. Also, you may be more likely to have problems after surgery or have a slower recovery than someone who had surgery for a less severe cataract.

Your doctor might recommend surgery if:

• Poor eyesight is affecting your ability to do your job or take part in some leisure or social activities.
• Surgery would help your doctor keep track of another eye problem, such as a problem with your retina.
• You do not have glaucoma, diabetic retinopathy, or macular degeneration. Surgery may not improve eyesight in people who also have these eye problems.

When children have cataracts that cause vision problems, surgery is usually needed.