Cataract surgery is usually very successful, but some children may experience complications and need further treatment.

Even if a child's cataracts are successfully removed during surgery, their vision may still be affected by other eye conditions.

For example, lazy eye can occur if there's weaker vision in 1 eye.

The brain ignores the visual signals coming from the weaker eye, which leads to the vision in the affected eye not developing properly.

Lazy eye will need further treatment, usually wearing a patch over the stronger eye, although it may not always be possible to fully correct the problem.

Cloudy vision

If your child has an artificial lens fitted during cataract surgery, the main risk is a condition called posterior capsule opacification (PCO).

This is where part of the lens capsule (the "pocket" that the lens sits inside) thickens and causes cloudy vision.

This is not the cataract returning, but is caused by cells growing over the artificial lens.

PCO is common after cataract surgery where an artificial lens is implanted, and it usually develops within 4 to 12 months of having the operation.

If your child develops PCO, they may need another operation to correct it.

Laser eye surgery, where energy beams cut through part of the eye, may be used.

During the procedure, the cloudy part of the lens capsule will be removed, with enough left to continue holding the artificial lens in place.

The procedure should only take around 15 minutes, and vision should be improved immediately or within a few days.

As no surgical incisions or stitches are necessary, your child can usually return to their normal activities straight away.

The Royal National Institute of Blind People (RNIB) website has more information about laser treatment for posterior capsule opacification (PCO)

Other complications


Other complications that can occur after an operation to remove childhood cataracts include:

Glaucoma is where vision is affected by increased pressure inside the eye.

Without successful treatment, glaucoma can cause irreversible damage to key structures in the eye and blindness.

It's a lifelong risk for children who have cataract surgery, so these children will need their eye pressure measured at least once a year by an optician for the rest of their lives.


A squint is where the eyes look in different directions.

Pupil abnormalities

This can include the pupil becoming a more oval shape. This is common and does not usually affect vision.

Retinal detachment

Retinal detachment is where vision is affected by the retina (the layer of light-sensitive cells that line the back of the eye) becoming separated from the inner wall of the eye.

Cystoid macular oedema

This is where fluid builds up between layers of the retina, sometimes affecting vision.


This can include endophthalmitis, a rare bacterial infection.

In many cases, medicine or further surgery will be required to treat these problems if they develop.

When to seek medical advice

You should immediately contact the hospital where the operation was carried out if your child has:

Page last reviewed: 13 April 2022
Next review due: 13 April 2025