The homework headache that is actually an eye problem
A child who sees the whiteboard perfectly can still have an eye problem that only appears at the width of a page. Here is the pattern I look for, how we measure it, and the one thing treatment does not do.
- A child can pass every distance sight test and still have an eye problem that only shows up during close work.
- The clue is timing: reading starts fine and falls apart after some minutes, with headaches, sore eyes, or words that move or double.
- Convergence insufficiency is measured with a target and prisms, not diagnosed by asking a child whether reading is hard.
- Supervised eye exercises with practice at home work better than home exercises alone, and a short course is what the evidence supports.
- Treating the eyes does not improve reading on a standardised test, so a child struggling with reading itself still needs a proper learning assessment.
The child who comes to me with this is usually eight or nine, and has usually been told, more than once, that he is not trying. He reads for ten minutes. Then the fidgeting starts, then the head goes down on the table, then there is a headache, and homework is the worst hour of the day for everybody in the house. On Saturday the same boy plays football for two hours and complains of nothing.
That pattern is worth taking to an eye doctor, because one particular eye problem produces it almost exactly. It is also where I am most careful about what I promise, because the largest trial on the treatment found something parents are hardly ever told.
He gets headaches after school every day, is it his eyes?
Sometimes, yes. There is one eye problem that behaves exactly like this, called convergence insufficiency. It means the two eyes cannot comfortably turn inwards together and hold there while your child works close up. The eyes are fine looking across the field. They struggle at the width of a page.
Convergence is the inward aim your eyes make when something comes close to your face. Every time your child looks down at an exercise book, both eyes swing in slightly and stay in for as long as the reading lasts. That is muscular work, and it can run out. When it does, one eye drifts outwards, the brain starts receiving two slightly different pictures, and the child gets a headache, sore eyes, or a page that will not hold still.
Plenty of after-school headaches have nothing to do with eyes. Skipped lunch, not enough water in a hot classroom, a late bedtime, tuition stacked on a full school day. What sends me to the eyes is not the headache on its own. It is the timing.
He can see the whiteboard fine, so how can it be his eyes?
Because seeing far and working near are two separate jobs, and only one is tested on a wall chart. In convergence insufficiency the outward drift happens only when the eyes focus at near. At distance the eyes are straight and the sight is sharp, so your child passes a distance test and the letter comes home saying his eyes are fine.
This is the commonest reason a parent tells me they were reassured and stayed worried. A screening measures the far chart because that is what a screening is for. It was never built to catch a pair of eyes that fail at twenty centimetres, and nobody should feel foolish for believing it. A full eye examination looks at both distances, on purpose, and it is the near job that asks most of the partnership between two eyes.
She says the words move on the page, what does that mean?
It usually means the two eyes have stopped pointing at the same word. The brain briefly receives two versions of the line, and a child describes it as words moving, swimming, doubling or going blurry. Others just say reading is horrible.
The symptoms I ask about are double vision, headaches and eye strain during reading, trouble concentrating on close work, and words that move or blur after a stretch of reading. Children often squint or close one eye over a book, because shutting one eye removes the second picture and lets the page settle. A child who reads with a hand over one eye is not being dramatic. She has found the workaround herself.
Four quieter signs are worth adding, because the American Academy of Ophthalmology lists them as easily missed: a short attention span for anything lengthy, losing his place on the page, avoiding close work, and turning the head to one side to look at something straight ahead. That last one points more towards a focusing error such as astigmatism, which is why the appointment checks everything and not only the thing you came in about.
Does he need glasses for reading?
Possibly, and it is measured first, before anyone talks about exercises. A child who is more long sighted than average, or has astigmatism, or has an unequal prescription between the two eyes, is already spending effort on focusing before the convergence work begins. Sometimes correcting that alone settles the whole complaint.
Focusing weakness and convergence weakness travel together. Testing the ability of each eye to focus alone at near often shows a weakness in children who have trouble converging, which is why the glasses question is answered first. If your child does come home with a prescription, what happens next with glasses is more ordinary than parents fear, and glasses do not weaken a child's eyes. That myth costs children more wearing time than anything else I meet.
What happens when you test for this?
We measure it rather than ask about it. The main measurement is how close a target can come to your child's nose before the eyes give up and it doubles, called the near point of convergence. The second is how much prism the eyes can overcome before the same thing happens. Both give a number, and a number can be repeated at the next visit to see whether treatment did anything.
One caution I give every family. A poor convergence reading in the room can simply mean a distracted, shy or over excited child, or one who did not understand what I asked. A bad result at four on a school afternoon gets repeated rather than acted on. Treatment is for children with symptoms. Some children have the finding and no complaints at all, and they need nothing from me.
Will eye exercises help?
For the symptoms, yes, and the trial evidence is unusually clear about which version of the exercises to do. In a randomised trial of 221 children aged nine to seventeen with symptomatic convergence insufficiency, office based vergence and accommodative therapy with home reinforcement improved or resolved symptoms in 73 per cent. Pencil push ups at home managed 43 per cent, home computer therapy plus push ups 33 per cent, and office based placebo therapy 35 per cent.
Two things follow. Supervised therapy with homework beats homework alone, so the pencil that has sat on your dining table since somebody online recommended it is the weakest option in the set. And a short course is what the evidence supports. Long stretches of therapy have not been shown to add more, so a programme that keeps extending is not following the trials.
Patching is the wrong tool here, and I say so because parents ask for it often. A patch forces the child to use one eye at a time, and the whole problem is the two eyes working together. Symptoms can return after an illness, a run of short nights, or a term with heavier near work. That is a reason for another short course, not a permanent programme. If screen homework is part of the load, the 20-20-20 break habit costs nothing to add, though I would not sell it to you as treatment.
Will it help his reading, or is this dyslexia?
Here I have to be blunt, because this is the sentence families most want to hear and the one the evidence does not support. Treating convergence insufficiency does not make a child read better on a test. In a trial of 310 children aged nine to fourteen, sixteen weeks of real vergence and accommodative therapy was set against placebo therapy, with reading comprehension as the main outcome. The real therapy group improved by 3.7 standard score points. The placebo group improved by 3.8. The difference was not statistically significant, and no secondary reading measure separated them either. The investigators wrote that clinicians should not suggest this treatment will improve standardised reading performance.
So keep the two questions apart. If the complaint is discomfort during near work, headaches, doubling, words moving, the eyes are worth measuring and treating, and the discomfort is what improves. If the complaint is reading itself, the decoding, the spelling, the slow progress there since Tahun 1, that belongs with the school and a learning assessment. Both can be true in one child, and each needs its own answer.
What to do this week is small. For a fortnight write down how many minutes into the work the headache arrives, whether it happens at the weekend, and whether it happens with a book but not with a football. Bring the exercise books, not a summary of them. Then book an eye examination and say plainly that the trouble is at near, so the near assessment happens in that visit. If what you have actually noticed is a child sitting closer and closer to the screen, that is a different clue pointing at short sight, and worth saying out loud too.
- The headache is severe and your child feels sick with it, or it wakes them from sleep.
- There is any change in sight, or it hurts your child to look at light.
- One pupil is bigger than the other, or one eye has visibly turned and stays turned.
- Your child sees double at a distance too, not only over a book.
- Your child has started tilting their head to one side or keeping one eye closed to see.
Common questions
The school screening said his eyes are fine, so should I still take him?
Does he need glasses for reading?
Will eye exercises help his reading?
Is this dyslexia?
Should I just patch one eye at home?
How long does the treatment take?
He only complains during tuition, not during school. Does that make sense?
- AAPOS · Convergence insufficiency · aapos.org
- Convergence Insufficiency Treatment Trial · Randomised clinical trial of treatments for symptomatic convergence insufficiency in children, Arch Ophthalmol 2008 · europepmc.org
- CITT-ART · Effect of vergence/accommodative therapy on reading in children with convergence insufficiency, Optom Vis Sci 2019 · pmc.ncbi.nlm.nih.gov
- American Academy of Ophthalmology · Four hidden signs of vision problems in kids · www.aao.org
- AAPOS · Glasses for children · aapos.org
- American Academy of Ophthalmology · What is eye strain · www.aao.org
- NHS · Red eye · www.nhs.uk