A headache with blurred or dim vision in a child: when the eye doctor looks at the optic nerve

Most childhood headaches have nothing to do with the eyes, and most are not serious. The NHS says so plainly. A small group of headaches comes with a particular pattern, though, and when it does, an eye doctor looks at the back of the eye, because the optic nerve can show a pressure problem that cannot be seen from outside.

This page sets out which pattern that is, what the eye doctor is looking for, what the finding can mean, why a harmless look-alike makes the picture harder to read, and which signs mean the emergency department today instead of an eye appointment. It describes published guidance. It cannot say what any one child has.

Is my child's headache coming from the eyes?

Usually not, and usually not from anything dangerous. The NHS advises that most headaches are not serious, and its list of common causes includes colds, stress, skipped meals, not drinking enough, and eyesight problems. Of those, the eye-related one is the focusing kind: a child whose eyes tire during near work and who feels better after a rest.

That pattern has its own page. The homework headache that is actually an eye problem covers the headache that arrives after reading, with glasses or eye exercises as the answer. If the headache comes with a shimmering zigzag line that fades in minutes, flashing lights and zigzag lines explains migraine aura. The action for both: a routine eye check, not an emergency.

Which headaches make an eye doctor look at the optic nerve?

The ones that behave as if there is pressure inside the head. Published descriptions of raised pressure share a set of features, and no single one proves anything. The pattern worth an urgent look is a headache with one or more of these:

• It is worse on waking, or when lying down, (EyeWiki describes the headache of raised pressure as positional, worse in the mornings and lying down).
• It is made worse by coughing, sneezing, bending down or straining. The NHS puts this in its urgent band for a child.
• It comes with vomiting, or wakes the child at night and is getting worse.
• Vision greys or darkens for a few seconds, in one eye or both, sometimes after a change of posture. These brief episodes are called transient visual obscurations.
• A pulsing or whooshing sound in the ears, in time with the heartbeat.
• A new squint, or double vision with the two images side by side. When a child says they see double explains how to sort this out at home first.

The action: a headache with any vision or eye problem sits in the NHS's urgent band, meaning an urgent appointment with a doctor and not the next routine slot. A family doctor, paediatrician or eye doctor can all start that. Bring a note of when the headaches come and what the child says about the vision.

What is papilloedema, in plain words?

It is swelling of the optic nerve head, the round spot where the nerve leaves the back of the eye, caused by raised pressure around the brain. The word is kept for swelling that comes from that pressure. Swelling from other causes is called optic disc oedema. Papilloedema is the British spelling; American pages write papilledema.

The pressure presses on the nerve behind the eye and slows the flow inside its fibres, and the head of the nerve swells up. It is usually seen in both eyes. It can build over weeks if the pressure rises slowly, or within hours to a day if it rises fast. If it is not dealt with, the fibres can be lost and vision can fall, which is why the finding is taken seriously.

Two facts matter for parents. First, papilloedema can be present with no eye symptoms at all, so the child may see normally and the dilated examination is how it is found or ruled out.

Second, how swollen the nerve looks does not say how serious the cause is, so a small amount of swelling is not a reason to relax. The action: a dilated eye examination, with photographs or an optical coherence tomography (OCT) scan of the nerve, is a short visit, and it gives the team facts to work from.

What causes papilloedema in a child?

Anything that raises the pressure inside the skull. The published lists group the causes by mechanism: a skull too small for the brain (craniosynostosis), something taking up space (a tumour or bleeding), blocked flow of the fluid around the brain, too much of that fluid made, or too little absorbed (meningitis, or a clot in the veins that drain the brain).

Sometimes no cause is found after full testing. That is called idiopathic intracranial hypertension, or IIH, and it is a diagnosis reached by excluding the others. In children before puberty it does not follow the adult pattern: EyeWiki notes that there is no leaning towards girls and that these children more often have a normal body weight.

Migraine and Down syndrome are listed as associated conditions. Pressure can also be raised by a medicine. The consensus guidelines list tetracycline-class antibiotics, vitamin A derivatives including isotretinoin, withdrawal from corticosteroids, and some hormone and thyroid medicines. A parent should not stop a prescribed medicine on their own; the prescriber needs to know about the headaches.

This is the reason the work-up moves quickly. It starts with the causes that cannot wait, whichever turns out to be the answer. The guideline for adults asks for an MRI of the brain within 24 hours and a scan of the veins to look for a clot, and EyeWiki likewise lists urgent imaging, after a blood pressure check, as the first step.

The action: if the eye doctor finds a swollen nerve, expect urgent imaging and a referral to the paediatric or neurology team, and treat it as a step forward, not a delay.

What is pseudopapilloedema, and why can't the eye doctor always tell by looking?

Pseudopapilloedema means a nerve head that looks swollen but is not. The most familiar cause is optic disc drusen, small deposits inside the nerve head that lift its edge and blur its outline. Other harmless variations also do it, such as a tilted disc or a disc that enters the eye at an angle, as can happen in short-sighted eyes.

The difficulty is real. A review in the Journal of Neuro-Ophthalmology calls telling disc swelling from pseudopapilloedema "a common, sometimes challenging clinical problem". Drusen in the young are often small and buried, so they sit out of view and still make the disc look raised, and they simulate low-grade papilloedema.

Drusen are found in an estimated 0.3 to 2.4 per cent of healthy people, and the same review notes that drusen and true papilloedema have been reported together, so finding drusen does not close the question when the headaches fit the pattern.

That is why more than one test is used. OCT is a quick scan that shows the shape of the nerve head, and an emerging consensus holds that it is the most sensitive way to find buried drusen. Ultrasound and autofluorescence photography can add to it, but each can miss small buried drusen.

The same review says OCT supplements the examination and does not replace it, and that it is especially helpful for following changes over time. Photographs taken at one visit and compared at the next show whether the nerve is stable. The action: if the answer is "probably drusen", ask when the nerve will be photographed again and which symptoms should bring your child back sooner.

When is a headache an emergency, and who looks after my child?

It is an emergency when the headache comes with a seizure, drowsiness or confusion, a sudden and extremely painful onset, a stiff neck with a very high temperature or discomfort from bright lights, a rash that does not fade under a pressed glass, weakness or numbness, trouble speaking or walking, a head injury in the past three months, or any loss of vision.

These are the NHS emergency signs for a child with a headache. Go to the emergency department. Do not wait for an eye appointment. My child says their eye hurts and when to go today lists the eye signs that also mean same-day care.

Outside those signs, the eye check is one part of a team. The paediatrician or neurologist leads the work-up of the pressure itself, with brain imaging and, where needed, a lumbar puncture to measure it. The eye doctor confirms or excludes the nerve swelling, records vision and the pupils, uses photographs and OCT to follow the nerve, and tells the team whether vision is at risk.

The consensus guidelines describe this as an interdisciplinary job that needs clear communication between clinicians, with timely re-examination wherever vision is threatened. Formal visual-field testing can be hard to do reliably in young children, so the eye doctor's notes on how the child sees day to day also count. The action: ask who is coordinating the plan, and keep every appointment, including the eye review after the scans.

Common questions

References

1. Mollan et al. · Idiopathic intracranial hypertension: consensus guidelines on management (Journal of Neurology, Neurosurgery and Psychiatry, 2018) · pmc.ncbi.nlm.nih.gov
2. Sibony · Optical coherence tomography neuro-toolbox for the diagnosis and management of papilledema, optic disc edema, and pseudopapilledema (Journal of Neuro-Ophthalmology, 2021) · pmc.ncbi.nlm.nih.gov
3. EyeWiki, American Academy of Ophthalmology · Papilledema · eyewiki.org
4. EyeWiki, American Academy of Ophthalmology · Pseudotumor cerebri (idiopathic intracranial hypertension) · eyewiki.org
5. NHS · Headaches, including when to get medical help · www.nhs.uk

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.