Childhood cataracts

Cataracts are cloudy patches in the lens of the eye that can make vision blurred or misty.

Information written and reviewed by Certified Doctors.

Contents

Introduction

Cataracts are cloudy patches in the lens of the eye that can make vision blurred or misty. They are called childhood cataracts (also known as congenital or infantile cataracts) when a child is born with them.

Cataracts in babies and children are rare. An estimated 200 children are born with cataracts every year.

They can develop in one or both eyes, and one eye can often be more affected than the other.

The lens (the transparent structure at the front of the eye) is normally clear. It allows light to pass through to the back of the eye. If parts of the lens become cloudy (opaque), light cannot pass through the cloudy patches.

Over time, these cloudy patches usually become bigger, and more of them develop. As less light is able to pass through the lens, vision may become blurry or cloudy. The cloudier the lens becomes, the more sight will be affected.

Read more about the symptoms of childhood cataracts.

Childhood cataracts are often referred to as:

  • congenital cataracts – cataracts that are present when a baby is born or shortly afterwards
  • developmental, infantile or juvenile cataracts – cataracts that are diagnosed in older babies or children

What causes cataracts in children?

In most cases of childhood cataracts, there is no family history and the exact cause is not known.

However, some possible causes include genetic conditions or infections during pregnancy. Read more about causes of childhood cataracts.

Although childhood cataracts that run in the family cannot be prevented, you may want to read about preventing childhood cataracts for advice on avoiding infections during pregnancy and genetic testing and counselling.

How are cataracts in children diagnosed?

In the UK, parents are offered two full physical examinations for their newborn babies as part of the [Healthy Child Programme], which includes a test for congenital cataracts.

Older children may show signs of cataracts if their vision is affected. For example, your child may:

  • have difficulty focusing on certain objects
  • hold their head at a certain angle
  • develop a squint

See your doctor if you are concerned about your child's vision.

Read more about diagnosing cataracts in children.

Treating cataracts in children

Cataracts can be mild in babies and children, and often have little or no effect on their vision. However, they can also slow down or stop the normal development of sight during childhood.

Cataract surgery can be performed to remove the cloudy lens and replace it with an artificial lens. Children will often need to wear glasses after the operation, or a patch to strengthen the vision in the weaker eye. Most children with childhood cataracts live a full and normal life.

Read more about how childhood cataracts are treated.

Are there any risks?

Cataracts that are not treated can sometimes cause irreversible damage to eyesight, including blindness.

Cataract operations are generally very successful, with a low risk of serious complications. The most common risk associated with cataract surgery is developing a condition called posterior capsule opacification (PCO), which causes cloudy vision to return.

If this happens, your child may need surgery to correct it. Speak to your opthalmologist before cataract surgery to discuss any risks.

Read more about the complications of childhood cataracts.

Symptoms

Symptoms of childhood cataracts can vary depending on how opaque (cloudy) the lens is, where the cloudiness is in the lens and whether one or both eyes are affected.

Identifying symptoms

In the UK, parents are offered two full physical examinations for their newborn babies as part of the [Healthy Child Programme], which includes a test for congenital cataracts.

Read about how childhood cataracts are diagnosed.

However, it can sometimes be difficult to identify the symptoms of cataracts in babies and children. Even older children may not realise there is anything wrong with how they see, as they do not know any different.

For example, if a child has a cataract in one eye, they may not notice that the vision in this eye is weak, because they rely on vision in their other eye.

If a child has cataracts in both eyes, one eye may be affected more severely than the other. This can cause the brain to learn to rely on the stronger eye. As a result, the weaker eye stops working as hard and its vision becomes weaker.

The position of the cataracts can also affect vision. For example, cataracts towards the centre of the lens may affect vision more than cataracts towards the side of the lens.

Older children

As a child gets older there may be more obvious signs of cataracts, especially if these are severely affecting the child's vision. For example, your child may:

  • have difficulty focusing on certain objects
  • hold their head at a certain angle
  • develop a squint

See your doctor if you or your child notice any changes in their vision so your child can be referred to an eye specialist.

A cataract rarely affects the appearance of the eye. If a child has a severe cataract, their pupil (the black circle in the middle of the eye) may look white or cloudy but this can be a sign of other serious conditions and should be treated as an emergency.

Other eye conditions

Children who have cataracts sometimes have other eye conditions as well. For example, they may have:

  • microphthalmia: abnormally small eyes
  • nystagmus: rapid uncontrolled eye movement

Causes

In many cases, it is not possible to determine the cause of childhood cataracts.

However, some possibilities are:

  • genetic conditions
  • infections during pregnancy

These are explained in more detail below.

Genetic conditions

Cataracts present from birth can be caused by genetic conditions. These are conditions that affect your genes (the units of genetic material that determine many of your body's characteristics) and can be inherited (runs in the family).

Cataracts can also be associated with conditions caused by chromosome abnormalities, such as Down's syndrome. Chromosomes are the parts of the body’s cells that carry the genes.

Infections

Cataracts present from birth can also be caused by infections caught by the mother during pregnancy. The most common infections include:

  • rubella (German measles): an infectious disease caused by a virus
  • toxoplasmosis: a condition contracted from eating uncooked meat, or from coming into contact with contaminated soil or cat’s faeces
  • cytomegalovirus: a common virus that is part of the herpes family of viruses
  • chickenpox: a mild but highly infectious condition caused by a virus

Other causes

Cataracts present from birth can also be linked to other eye conditions, including:

  • retinopathy of prematurity: a condition found mainly in babies born before week 37 of pregnancy
  • aniridia: a rare condition where the iris (the coloured part of the eye) is not formed properly

Conditions that affect the body's metabolism (the process that turns food into energy) can sometimes cause cataracts to develop in older babies or children, although these are rare. For example:

  • galactosaemia: when the sugar galactose (which mainly comes from lactose, the sugar in milk) cannot be broken down by the body
  • diabetes: a chronic (long-term) condition caused by too much glucose in the blood

Eye injuries can also cause cataracts sometimes.

Diagnosis

It is important congenital cataracts (cataracts you are born with) are diagnosed as early as possible, ideally during the first few weeks after a baby is born. This will reduce the chances of sight loss.

Screening of newborn babies

In the UK, parents are offered two full physical examinations for their newborn babies as part of the [Healthy Child Programme]:

  • the first within 72 hours of the baby's birth
  • the second when the baby is about six-to-eight weeks old

Congenital cataracts are among the conditions screened for in these examinations.

During screening your baby's eyes are checked by looking at their general appearance and how they move. If your baby’s eye looks cloudy, it could be a sign they have cataracts.

Sometimes, it can be difficult to check the eyes of newborn or very young babies because:

  • Their eyelids are swollen.
  • Their eyes are closed.
  • They are unsettled, anxious or irritated.

Even though cataracts may be present from birth, sometimes they are not diagnosed until the child is older. All children under the age of 16 are entitled to free sight tests, which they should have every two years or so.

Checking children's eyes

If it is thought your baby or child may have cataracts, they will be referred to either:

  • an ophthalmologist: a medical doctor who specialises in eye conditions and their treatment or surgery
  • a paediatric ophthalmologist: a medical doctor who specialises in treating children's eyes

Other healthcare professionals may also be involved, such as a paediatrician (a doctor who specialises in children's treatment).

Before the ophthalmologist examines your baby, they will apply drops to their eyes to dilate (widen) the pupils (the black circle in the middle of the eye). The drops will not hurt your baby, and the effect will wear off after a few hours.

The ophthalmologist will then examine your baby's eyes using an ophthalmoscope (a medical instrument that has a light on the end and produces a magnified image of your eye). This shines a bright light into your child’s eyes and enables the ophthalmologist to look inside them.

The ophthalmologist may diagnose cataracts if:

  • They can see the cataracts in the lens.
  • The examination shows a poor "red reflex" in the pupil.

The red reflex is like a reflection from the back of the eye similar to the red eye effect sometimes seen in flash photography. If the examination shows no red reflex, or is weaker than usual, there may be cloudiness in the lens.

Other tests

If there is no family history of childhood cataracts, your ophthalmologist may also suggest some other tests to identify the cause of the cataracts and confirm the diagnosis. For example, your child may have:

Treatment

Cataracts in children do not always need to be treated if they are not causing problems. Surgery is used to treat cataracts affecting vision.

If your baby or child has cataracts, need for treatment may depend on:

  • whether one or both eyes are affected
  • how mild or severe the cataracts are

Childhood cataracts are rare, so it can be difficult to predict how much a child’s vision will be improved by treatment.

Cataracts in babies and children may be treated by:

  • using surgery to remove the cloudy lens and replacing it with an artificial lens
  • wearing glasses
  • wearing contact lenses
  • a combination of these treatments

Surgery

Cataract operations for babies and children will take place in hospital under general anaesthetic (a painkilling medication that makes you unconscious). The operation will be performed by an ophthalmologist (a medical doctor who specialises in eye disease and its treatment or surgery).

If the cataracts are present from birth, the operation will be carried out as soon as possible, usually a few weeks after your baby is born.

Before the operation, the ophthalmologist will apply drops to the eye to dilate (widen) the pupil (the black part at the centre of each eye). A very small incision (cut) is made in the surface (cornea) at the front of the eye, and the cloudy lens is removed.

Without the lens, the eye cannot focus. To correct this, the natural lens may be replaced with a clear plastic lens. This is called an intraocular lens (IOL) or intraocular implant.

Sometimes, a contact lens on the eye's surface may be used instead of an IOL. This will be fitted one-to-two weeks after the operation. This may be particularly useful in babies and children with anterior uveitis.

There is a higher risk of complications and further surgery being needed in babies who have an IOL inserted.

After the operation

After the operation, a pad will be placed over the eye to protect it. Babies under the age of three months old will probably need to stay in hospital overnight due to the anaesthetic. You may be able to stay with them. Older children usually go home after the operation.

If your child has cataracts in both eyes (bilateral cataracts), the ophthalmologist will probably operate on each eye separately. You and your child will be able to go home between operations. The second operation will be about a week later.

You will be given eye drops to give to your baby or child at home. These help reduce inflammation (swelling and redness) in the eye. You will need to put them into the eye every two-to-four hours, and you will be shown how to do this before you leave hospital.

Read more about cataract surgery.

Further treatment

After a cataract operation, your child will have regular check-ups with an orthoptist. An orthoptist specialises in problems that relate to eye movements and how the eyes work together.

They will test your child’s vision regularly to pick up and correct changes in their vision as early as possible.

Most children will need to wear:

  • glasses or contact lenses to improve their vision: these will probably be fitted a few weeks after the operation
  • a patch over their eye: this is called occlusion therapy (see below) although sometimes drops can be used to blur vision in the stronger eye rather than wearing a patch

Contact lenses can be used in babies as well as older children. You will be taught how to insert the contact lenses for your child, and how to look after the lenses.

Occlusion therapy

In occlusion therapy, the stronger eye (the eye that sees best) is covered with a patch. This means that the child only uses the weaker eye to see.

This treatment aims to improve vision in the weaker eye. It makes the brain recognise the visual signals from that eye and improves the images it sees.

Your orthoptist will tell you when your child should wear the patch and how long they may need it for. This will depend on the type of cataract your child had, and how weak their vision is. Wearing a patch can be an unpleasant experience for your child, and they will need lots of encouragement to keep it on.

Complications

Although cataract surgery is very successful, some children may experience complications and need further treatment. All children will need to wear glasses after the operation.

Even if a child's cataracts can be treated successfully, improvement to their vision may be affected by other eye conditions. For example, lazy eye (amblyopia) is an early childhood condition where vision does not develop properly. This will need further treatment, usually by wearing a patch (occlusion therapy) or using eye drops.

Complications from surgery

Cloudy vision

The most common risk associated with cataract surgery is developing 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 due to cells growing over the back of the artificial lens.

PCO is common, affecting up to half of all people who have cataract surgery. PCO usually develops between six months and five years after the operation.

If this happens, your child may need another operation to correct it. This will be done with laser eye surgery (when energy beams are used to cut through part of the eye). During laser eye surgery, the cloudy part of the lens capsule will be removed, with enough left to continue holding the artificial lens in place.

This 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.

Other complications

Other complications can arise from an operation to remove childhood cataracts. The Royal National Institute for the Blind (RNIB) estimates that these complications occur in around 2% of cases. These can include:

  • glaucoma: increased pressure inside the eye, which affects vision
  • squint (strabismus): a condition where one eye turns inwards, outwards, upwards or downwards, while the other eye looks forwards
  • abnormalities affecting the pupil (the black circle at the centre of each eye)
  • retinal detachment: when the retina (the layer of nerve cells inside the back of the eye) becomes separated from the inner wall of the eye
  • infection: for example, endophthalmitis (a rare bacterial infection)

If your child has any signs of pain, bleeding, a lot of stickiness or redness in or around the eye after surgery, contact the hospital immediately.

Cystoid macular oedema

One possible complication that can cause loss of vision is cystoid macular oedema. This is where fluid builds up between layers of the retina (the layer of nerve cells that lines the inside of the back of the eye).

There are two different types of cystoid macular oedema:

  • angiographic cystoid macular oedema
  • clinical cystoid macular oedema

Angiographic cystoid macular oedema is common, but does not affect vision. Clinical cystoid macular oedema can cause vision loss and makes up between 0.1% and 12% of cases.

Cystoid macular oedema may be treated with non-steroidal anti-inflammatory drugs (NSAIDs), although it's notable that research into this is still continuing.

Wearing glasses

The natural lens in your eye can change shape. This is how it enables your eyes to focus on objects both near to you and further away.

Fixed strength (monofocal) and multifocal replacement plastic lenses can't do this. After cataract surgery, your child may also need reading glasses or glasses for distance vision.

All children will usually need to wear either contact lenses, glasses or both after cataract surgery. Often, babies can have contact lenses for the first two years or so until the eye "grows into" the intraocular lens (IOL). Multifocal IOLs are rarely used in babies or children.

Prevention

Childhood cataracts that are inherited (run in the family) can't be prevented.

Pregnancy

If you're pregnant, follow the advice of your midwife or doctor to avoid infections during pregnancy.

If you want to try for a baby, but don't know whether you are immune to rubella (German measles), ask your doctor to check your immunity. If necessary, you can be vaccinated against rubella with the MMR vaccine (a vaccine that prevents measles, mumps, and rubella).

After having the MMR vaccine, make sure you avoid becoming pregnant for one month afterwards.

Genetic counselling

If you have previously had a baby with childhood cataracts, and are planning another pregnancy, you may wish to speak with your doctor about whether genetic counselling would be appropriate.

Genetic counselling can help couples who may be at risk of passing a genetic condition (a condition inherited from a family member) onto their child.

Read more about genetic testing and counselling.

Content supplied by NHS Choices