Cataract in children: not only a grandparent's problem

Katarak is a grandmother word. In most Malaysian families it belongs to an aunty who had her eyes done in her seventies and came back delighted with the world. So when I say the word in a room with a baby in it, I watch the same thing happen every time. The parent looks at me, then at the baby, then back at me, and asks whether I have mixed up the notes.

I have not. The lens inside the eye can be cloudy at any age, including at birth. AAPOS puts childhood cataract at around three children in every ten thousand worldwide, and the NHS gives three to four in every ten thousand babies born in the United Kingdom. Neither is a Malaysian figure and I have none to give you. Rare, then, but not so rare that a paediatric eye clinic goes a year without it.

Can a baby really have a cataract?

Yes, and it is worth separating two words you may hear used loosely. A congenital cataract is one that is present when a baby is born or appears shortly afterwards. A developmental, infantile or juvenile cataract is one picked up later in a baby or an older child. The cloudiness is the same thing. The timing changes what we do about it.

Causes exist and often stay unfound. An inherited fault in the genes, a lens that simply did not form correctly before birth, a genetic condition such as Down's syndrome, or an infection during pregnancy including rubella and chickenpox are all on the list, and so is an injury to the eye after birth. In many children no cause is ever identified. AAPOS also notes that most childhood cataracts are found on their own and are not part of some wider illness in the body.

I say the next part because a mother in this room is usually already writing her own charge sheet. Nothing you did in pregnancy caused this. It was not screens, not sunlight, not what you ate, not the fall you keep thinking about.

I saw a white spot in my baby's pupil, what is it?

It needs looking at this week by someone who can see inside the eye, and I would rather you read that sentence than a reassuring one. A cloudy lens is one of the things that turns a pupil white or grey instead of black, and a parent noticing exactly that is one of the three usual ways childhood cataract is found. The other two are the red reflex check after birth and a routine baby check-up.

It is not the only thing that makes a pupil look pale, which is why the check is urgent rather than optional. A white glow in a flash photograph has its own article on this site and its own list of causes, some of them entirely innocent and one of them not. Nobody sorts that out by looking at the photograph again. It is sorted out with drops and a light.

Two other signs bring babies to me with a cataract behind them. Eyes that wobble or shake, and a squint, where the eyes point in different directions. If your baby has either of those, a cloudy lens is one of the things being ruled out at the appointment, which is part of why the first eye checks of a baby's life are worth turning up for even when everything looks well.

Why is it more urgent in a baby than it was for my mother?

Because your mother's brain already knew how to see and your baby's does not yet. That single difference is the whole of it. In an adult, a cataract sits in front of a finished visual system, blurs the picture, and can be removed next year with the same result as this year.

In a baby, the seeing part of the brain is still being built, and it is built out of whatever the eye sends it. A cloudy lens does not simply blur that signal. It starves the developing pathway of the clear image it needs, and the eye can end up permanently weak even after the cloudiness is gone. We call that amblyopia, a lazy eye, and it develops silently, without a child ever complaining.

So the clock is real, and it is short. That is why a cloudy lens present from birth is not put on a list for next year, and why I ask families to come back at short notice for something that looks, to them, completely stable.

How soon does it need an operation?

Very soon, when it is blocking the light. For cataracts present from birth, the NHS states that the operation is carried out as soon as possible, usually one to two months after the baby is born. Read that twice. Not one to two years. One to two months.

Not every childhood cataract needs surgery at all, and this is the part that gets lost when a frightened parent reads the first half of the sentence. Some are small, or sit off to the side of the lens, and leave the vision unaffected. Those are watched rather than operated on, with regular appointments, because a small cataract can grow or start to matter as a child gets older. If your child's cataract is being monitored instead of removed, that is a decision, not a delay.

The other kind arrives later and by accident. A cataract can form after an injury to the eye, sometimes straight away and sometimes many years afterwards, which is one more reason the ordinary hazards around a house are worth an hour of your attention.

What actually happens at the operation?

A general anaesthetic, a very small cut at the edge of the cornea, and the cloudy lens removed through it. The NHS describes an operation that usually takes between one and two hours, with dilating drops given beforehand and dissolving stitches used at the end. If both eyes are affected, each eye is usually done separately, the second commonly within a week of the first, to keep any complication from involving both eyes at once.

Expect an overnight stay, a pad or a shield over the eye afterwards, and drops at home every two to four hours for a period. That drop schedule is the part parents find hardest, harder than the surgery itself, and it is worth practising the technique before you need it.

Taking the lens out leaves the eye without its focusing power, so the focus has to be replaced. There are three ways: a lens implanted inside the eye, a contact lens on the surface, or glasses. In babies under twelve months at the time of surgery, most ophthalmologists prefer a contact lens or glasses, because implants in very young eyes carry a higher risk of complications and of further surgery. Glasses after cataract surgery can be thick and make things look bigger, which is why they suit a child who has had both eyes done better than a child with one clear eye and one operated one.

Will she see normally afterwards?

I cannot promise you that, and no honest eye doctor will. The NHS puts it plainly: it is difficult to predict how much better a child's vision will be after treatment, there is likely to always be some degree of reduced vision in the affected eye, and many children born with childhood cataracts do not grow up to have serious problems with their sight. All three of those sentences are true at the same time.

What I can tell you is that the surgery is the first half of the treatment, not the whole of it. The eye that spent weeks looking through cloud is behind the other one, and it catches up only if it is made to work. That means patching the stronger eye, often for months, and without it most children who had a cataract in one eye will not develop good vision in the operated eye. Getting a small child to accept a patch is its own skill and there is no shame in finding it hard.

How much of this you can influence is limited, and it is worth knowing which part is yours. Coming early, keeping the follow-up appointments when nothing seems to be happening, and treating the patch as seriously as the operation are the three that sit with the family rather than with the surgeon. They are also the three I most often see slip when a child looks well.

Common questions

References

1. AAPOS · Cataract · aapos.org
2. NHS · Childhood cataracts · www.nhs.uk
3. NHS · Childhood cataracts, treatment · www.nhs.uk
4. AAPOS · Amblyopia (lazy eye) · aapos.org
5. American Academy of Ophthalmology · Amblyopia (lazy eye) · www.aao.org
6. NHS · Retinoblastoma, symptoms (the white reflection in the pupil) · www.nhs.uk
7. American Academy of Ophthalmology · Eye screening for children, including family-history risk · www.aao.org

By Dr Chan Li Yen. General information only. It does not replace a consultation. If you are worried about your child's eyes or vision, please see an eye doctor.