How Eye Alignment Is Measured: The Tests Behind a Strabismus Disorder Diagnosis

The photo was meant to be a keepsake: a toddler on a picnic blanket, grinning at the camera. Yet in the flash, one eye looked straight ahead and the other seemed to drift toward her nose. Her father zoomed in, scrolled back through older pictures, and found the same thing in three of them. By bedtime he had a question he could not put down: is this something, and how would anyone even check?

The answer is reassuringly concrete. Strabismus eye exam tests are among the most low-tech procedures in medicine. A paddle, a penlight, a handful of wedge-shaped prisms and a trained pair of eyes do most of the work. No scanner is needed to tell whether two eyes are pointing at the same target.

What follows explains each of those tests in plain language: what the examiner is watching for, what the numbers mean, who is examined promptly and who is usually asked to wait, and which signs should never wait for a routine appointment.

What strabismus eye exam tests are actually looking for

Strabismus is the medical term for eyes that do not point at the same spot at the same time; one eye fixes on the target while the other turns in, out, up or down. The NHS notes that squints, its everyday word for the condition, affect around 1 in 20 children, and that adults can develop them too.

Every test in the exam answers one of four questions. Is there a misalignment at all? Which direction does the eye turn? How large is the turn, measured in units the team can track over time? And what is the misalignment doing to vision, particularly in a child whose visual pathways are still wiring themselves?

That last question matters most. The brain of a young child will quietly switch off the picture from an eye that is consistently turned, to avoid double vision. Over months, that suppressed eye can develop amblyopia, reduced vision that persists even with the right glasses. The National Eye Institute estimates amblyopia affects up to 3 out of every 100 children, and strabismus is one of its main causes. So the exam is never only about cosmetics or a photo; it is a check on whether both eyes are being used and developing.

Examiners also distinguish a tropia, a turn that is present when both eyes are open, from a phoria, a tendency to drift that appears only when the eyes are prevented from working together. Most people have a small phoria and never notice it. The tests below are designed to separate the two, because they carry very different implications.

How the cover test for strabismus actually works

Ask any eye specialist to name the single most useful test for strabismus and most will say the cover test. It needs an occluder, a small paddle, and a target for the patient to look at: a letter on the chart for older children and adults, a small toy or light for toddlers.

The examiner covers one eye and watches the uncovered eye. If that eye jumps to pick up the target, it was not looking at the target while both eyes were open. In other words, it was turned, and the direction of the jump reveals the direction of the turn. An eye that moves outward to fix was turned inward (esotropia); an eye that moves inward was turned outward (exotropia). This is the cover-uncover test, and it detects a tropia.

Next comes the alternate cover test. The paddle swings from one eye to the other without ever letting both eyes see the target together. This breaks the brain’s ability to fuse the two images, so any hidden tendency to drift, a phoria, shows up as a movement when each eye is uncovered.

Both parts are repeated with the target far away and then close up, usually at reading distance. Some misalignments only appear at one distance, especially the type of inward turn linked to focusing effort in farsighted children. Cleveland Clinic and Johns Hopkins both describe the cover test as a standard component of the strabismus examination, and it is repeated at every visit because it costs nothing and shows change over time.

Children rarely object. The whole sequence takes a minute or two, and a good examiner turns it into a game of peekaboo.

What the Hirschberg test shows with a penlight

Before any paddles come out, the examiner often shines a small light toward the patient from about arm’s length and looks at the reflection on each cornea, the clear front surface of the eye. This is the Hirschberg test, also called the corneal light reflex test.

When both eyes are aligned, the tiny reflection sits in roughly the same place on each pupil, usually just slightly toward the nose of center. If one eye is turned, its reflection is displaced. A reflex shifted toward the outer edge of the pupil suggests the eye is turned inward; a reflex shifted toward the nose suggests it is turned outward.

The test is quick, needs no cooperation beyond a glance at the light, and works in babies who cannot yet follow instructions, which is why MedlinePlus lists the corneal light reflex among the basic assessments for strabismus. It also has an honest limitation: it is an estimate. Each millimeter of displacement corresponds only roughly to a set number of degrees of turn, and the examiner is judging by eye.

The Hirschberg test earns its place for another reason. It helps sort true strabismus from pseudostrabismus, the appearance of crossing caused by a wide, flat nasal bridge or extra skin folds at the inner corners of a young child’s eyes. In pseudostrabismus the light reflexes are symmetric, even though the eyes look crossed in photographs. Many of the families who arrive worried by a picture leave with exactly this explanation, but it is a call for the examiner to make, not one to assume at home.

Prism cover test: how eye alignment is measured in numbers

A prism is a wedge of glass or plastic that bends light toward its thicker edge. Held in front of a turned eye, a prism of the right strength moves the image so that the eye no longer has to move to pick it up. That principle turns the cover test into a measurement.

During the prism cover test, the examiner performs the alternate cover test while holding prisms of increasing strength in front of one eye. When the eye stops making a refixation movement, the misalignment has been neutralized, and the strength of that prism is the size of the deviation. The unit is the prism diopter, written as a triangle symbol on clinic notes; one prism diopter shifts an image by one centimeter at a distance of one meter.

Cleveland Clinic describes the prism test as the way specialists quantify how far the eye turns, and the number matters for several reasons. It lets the team distinguish a small, stable deviation that may simply be observed from a large one that is more likely to be affecting vision. It provides a baseline, so that a repeat measurement months later shows whether things are stable, improving or worsening. And it is the figure a surgeon works from if an operation is ever considered, because the amount of muscle adjustment is planned around it.

Measurements are typically taken at distance and near, and often with the head turned or tilted or the gaze directed up and down, because some deviations change with gaze direction. That pattern helps identify whether a particular eye muscle is weak or restricted rather than simply misaligned.

For a child too young to cooperate with alternating covers, the Krimsky method combines prisms with the light reflex, moving the corneal reflection back to center rather than watching for refixation.

Why a dilated exam and cycloplegic refraction belong in strabismus eye exam tests

A surprising amount of childhood strabismus begins with the focusing system rather than the eye muscles. A child who is significantly farsighted has to focus hard to see clearly, and the effort to focus is neurologically linked to the effort to converge the eyes. Push one and the other follows, so the eyes drift inward. This accommodative esotropia often improves substantially once the farsightedness is corrected with glasses, which is why measuring refractive error accurately is part of every strabismus workup.

Children are very good at hiding farsightedness by focusing, so an ordinary refraction can underestimate it. The examiner therefore uses cycloplegic drops, a class of eye drops that temporarily relax the focusing muscle and widen the pupil. With the focusing system switched off, a retinoscope, a handheld light that reflects off the back of the eye, reveals the true prescription. Mayo Clinic notes that dilating drops can blur near vision and increase light sensitivity for several hours afterward, so a child may want sunglasses and may struggle with reading for the rest of the day.

The widened pupil serves a second purpose. It allows the doctor to examine the retina and optic nerve directly. This is not optional. Occasionally a new eye turn is the first sign that one eye simply does not see well, because of a cataract, a scar at the macula or, rarely, a tumor at the back of the eye. Johns Hopkins lists a dilated examination among the standard components of a strabismus evaluation for precisely this reason: the team needs to know that the eye which is turning is structurally healthy before treating the alignment alone.

Which drops are used, and how they are given, is decided by the examining clinician based on the child’s age and needs.

Which other eye alignment tests fill in the picture

Alignment is one measurement; how the two eyes function together is another, and several short tests address it.

Visual acuity comes first. For a child who cannot read letters, examiners use matching pictures, symbol charts or, in infants, preferential looking cards that rely on a baby’s instinct to gaze at stripes rather than a blank grey field. A difference in vision between the eyes raises the concern for amblyopia and changes the urgency of the plan.

Ocular motility testing follows the eyes through the nine positions of gaze: straight ahead, left, right, up, down and the four diagonals. The examiner is looking for an eye that lags, overshoots or cannot reach a position, which points toward a weak or restricted muscle or a nerve problem rather than a straightforward childhood squint.

Stereoacuity, depth perception built from two slightly different images, is tested with polarized glasses and a booklet of pictures that appear to lift off the page. MedlinePlus lists stereopsis testing among the standard strabismus assessments. A child with constant strabismus often has reduced or absent stereopsis, while good stereo is reassuring evidence that the eyes are working together at least some of the time.

Sensory tests such as the Worth four-dot test, using red and green glasses and colored lights, show whether the brain is fusing both images, suppressing one, or seeing double. In adults with a new eye turn, the examiner also asks carefully about double vision, because diplopia is a symptom that childhood strabismus usually spares and adult-onset strabismus often causes.

None of these takes more than a few minutes. Together they turn a single number, the size of the deviation, into a working understanding of what that deviation is doing to the person who has it.

Strabismus eye exam tests at a glance

Parents and adult patients often want to know why so many small steps are needed when the misalignment seems obvious. The table below sets out what each test contributes and what it cannot do on its own. Information on each test is consistent with descriptions from MedlinePlus, Cleveland Clinic and Johns Hopkins.

Test	What the examiner does	What it tells the team	Main limitation
Hirschberg (corneal light reflex)	Shines a light and compares the reflection position on each cornea	Quick screen for a turn; helps separate true from pseudostrabismus	Estimate only; misses small deviations
Cover-uncover test	Covers one eye, watches the other for a refixation movement	Confirms a manifest turn (tropia) and its direction	Needs the patient to fix on a target
Alternate cover test	Swings the occluder between eyes without allowing fusion	Reveals latent drift (phoria) plus the full deviation	Cannot by itself distinguish phoria from tropia
Prism cover test	Repeats alternate cover with prisms until movement stops	Measures the deviation in prism diopters, at distance and near	Requires cooperation; less precise in restless toddlers
Krimsky	Uses prisms to center the corneal light reflex	Approximate measurement in infants and low-vision eyes	Less accurate than prism cover test
Motility in nine gaze positions	Has the patient follow a target in every direction	Identifies weak, restricted or overacting muscles	Subtle limitations need experienced interpretation
Stereoacuity and sensory tests	Polarized or red-green glasses with special targets	Shows whether the brain fuses, suppresses or sees double	Depends on age and understanding
Cycloplegic refraction and dilated exam	Drops relax focusing; retinoscope and ophthalmoscope used	Finds hidden farsightedness; checks retina and optic nerve	Blur and light sensitivity for hours afterward

No single row is sufficient. The cover test confirms, the prism cover test measures, and the dilated exam protects against missing a structural cause.

Who is usually tested promptly, and who is usually asked to wait

Newborns have not yet learned to coordinate their eyes. The NHS explains that it is common for a baby’s eyes to cross or drift occasionally in the first months of life, and that this usually settles as visual control matures. For that reason, an intermittent turn in a baby under about 3 months is typically observed rather than investigated, unless it is constant, one eye never seems to straighten, or something else about the eye looks unusual.

After that window the picture changes. The NHS advises that a squint which is still present, or appears for the first time, beyond 3 months of age should be assessed, because the eyes should be working together by then. In practice, most children referred for strabismus eye exam tests fall into a few groups: those whose parents or a health visitor noticed a turn, those flagged by routine vision screening at preschool or school entry, and those with a family history of strabismus or amblyopia, which raises the chance of the same problem.

Children who are premature, have a neurodevelopmental condition such as cerebral palsy or Down syndrome, or have had a head injury are also examined more readily, since Cleveland Clinic and MedlinePlus both list these as factors associated with strabismus.

Adults are a different case. A long-standing childhood turn that has never caused symptoms can be examined at any convenient time. A new eye turn in an adult, particularly with double vision, is not something to watch. It may reflect a problem with a nerve supplying an eye muscle, thyroid eye disease, a small stroke or raised pressure in the head, and the examination is usually arranged quickly rather than deferred.

Where any individual sits on this spectrum is a judgment for the examining clinician, who can weigh the whole history rather than a single sign.

Should I see an optometrist or an ophthalmologist for strabismus?

Both can help, and in many health systems the path runs through both.

An optometrist is a primary eye care professional trained to test vision, prescribe glasses and detect eye disease. Optometrists routinely perform the cover test, measure alignment and carry out cycloplegic refraction in children, and they are often the first to identify a squint during a routine sight test. Some specialize in binocular vision and manage certain types of intermittent or convergence-related problems long term.

An ophthalmologist is a medical doctor who specializes in eye disease and surgery. Within ophthalmology, pediatric ophthalmologists and strabismus specialists focus specifically on children’s eyes and on eye alignment in all ages, including the surgical adjustment of eye muscles. Orthoptists, allied health professionals who specialize in eye movement and binocular vision, frequently perform the detailed measurements in these clinics.

The NHS pathway illustrates a common model: concerns are raised with a general practitioner, health visitor or optometrist, and a child with a suspected squint is referred to a hospital eye service where an orthoptist and ophthalmologist carry out the full assessment. In the United States, a pediatrician’s screening or an optometrist’s finding usually leads to referral to a pediatric ophthalmologist when a constant turn, reduced vision in one eye or an unusual pattern is found.

A sensible way to decide is by urgency and complexity. For a routine check, a first look at a photo concern, or glasses follow-up, an optometrist is well placed. For a constant turn in a young child, a suspected difference in vision between the eyes, any adult with new double vision, or any question of surgery, an ophthalmologist with strabismus expertise is the appropriate destination, and a good optometrist will make that referral without hesitation.

What test confirms strabismus, and is there a gold standard?

People searching for a gold standard often expect a machine and a printout. For strabismus, the reference test is the cover test performed by an experienced examiner, with the prism cover test providing the measurement. Cleveland Clinic, Johns Hopkins and MedlinePlus each describe this combination as the standard clinical assessment, and no imaging study replaces it.

Confirmation therefore rests on a direct observation: an eye that moves to take up fixation when its partner is covered. If that movement is seen consistently, the diagnosis is made. Its size is then recorded in prism diopters, and its behavior across distance, near and different gaze directions is charted. The examiner adds the light reflex test in the very young, motility testing to assess the muscles, and a dilated exam to check that the eye itself is healthy.

Photoscreeners and automated vision screening devices deserve a word, because families sometimes encounter them at a pediatrician’s office or a school. These handheld instruments photograph the light reflex in both eyes and flag possible misalignment or refractive error. They are screening tools, useful for identifying children who need a full examination, and they are not diagnostic. A flagged result should lead to the cover test, not stand in for it.

Imaging such as MRI or CT is reserved for situations where the history or examination suggests something beyond a typical childhood squint: a new turn in an adult, an eye that cannot move fully in one direction, pain, a droopy lid or other neurological signs. In those cases the scan is looking for the cause, not confirming the strabismus, which the cover test has already done.

The honest summary is that the confirming test is old, simple and dependent on skill. That is a strength. It can be repeated at every visit, by any trained clinician, without special equipment.

What are the early warning signs of strabismus?

Because a young child does not complain of double vision, the earliest clues are things other people notice. The commonest is simply an eye that looks turned, either constantly or when the child is tired, unwell or daydreaming. Intermittent turns are easy to dismiss precisely because they come and go, yet the NHS advises that any squint seen after 3 months of age should be checked.

Photographs are genuinely useful here. A red reflex that looks different in the two eyes in a flash picture, or a light reflection that sits in different places on each pupil, is worth mentioning to a clinician, even though most such photos turn out to show pseudostrabismus or a trick of the angle.

Some children adopt a head posture, tilting or turning the head to line up their eyes and avoid seeing double. A persistent tilt that the child returns to after being straightened can be a sign of a vertical or paralytic strabismus and is a reason for examination in its own right.

Squinting one eye shut in bright sunlight is a classic feature of intermittent exotropia, an outward drift that appears at distance; closing one eye is the child’s way of switching off the second image. Older children may mention that things look double, that they lose their place when reading, or that they bump into objects on one side.

In adults, the warning sign is usually double vision, which Mayo Clinic notes is a hallmark of misalignment that develops after childhood, since the adult brain cannot suppress an image the way a young child’s can.

None of these observations makes a diagnosis. They are reasons to book an examination, where the tests described above will settle the question.

What the days and weeks after a strabismus exam usually look like

The exam itself is done in an afternoon. What follows depends on what it found.

On the day, expect the effects of the dilating drops to linger. Mayo Clinic notes that near vision stays blurry and eyes stay light-sensitive for several hours; some longer-acting drops used in young children can affect focusing into the next day. Sunglasses, a hat and a break from screens and homework make the evening easier.

If significant farsightedness was measured, glasses are usually the first step. The team will often ask to see the child again after a period of full-time wear, commonly a matter of weeks, to repeat the cover test with the glasses on. In accommodative esotropia the turn may be markedly smaller with the glasses in place, and that finding shapes everything that follows.

If one eye sees less well than the other, treatment for amblyopia typically begins alongside, most often patching the stronger eye or blurring it with drops for part of the day so the weaker eye is forced to work. The National Eye Institute describes both approaches and notes that treatment is most effective in early childhood, with regular reviews to check progress. Duration is set by the treating team based on response, not a fixed calendar.

Where a turn is small, intermittent and vision is equal, the plan may be observation with repeat measurements at intervals, because some intermittent deviations remain stable for years. Where a turn is large and constant, or does not improve with glasses, the ophthalmologist may discuss surgery to adjust the eye muscles, using the prism cover test measurements as the plan. That is a separate conversation, and the timing and choice rest with the family and the treating team.

For adults with a new turn, the following weeks may involve blood tests or imaging to find the cause, and temporary prism lenses to manage double vision while that happens.

What people often get wrong about strabismus testing

“Children grow out of a squint.” Some newborn drifting settles by about 3 months, but the NHS is clear that a squint persisting beyond that age will not correct itself and should be assessed. Waiting risks amblyopia, which becomes harder to treat as the visual system matures.

“If the eye looks straight most of the time, it is fine.” An intermittent turn still means the brain is periodically receiving two different images and may be learning to suppress one. The cover test can detect and measure a deviation that is invisible to family most of the day.

“A scan would be more accurate.” Imaging shows anatomy, not alignment. The prism cover test in skilled hands measures the deviation to within a few prism diopters, and it is the measurement surgeons plan from. Scans are for finding causes in specific situations, not for diagnosis.

“Eye exercises fix strabismus.” Exercises have a role in one specific problem, convergence insufficiency, where the eyes struggle to turn inward for near work. For a constant esotropia or exotropia, there is no good evidence that exercises realign the eyes, and relying on them can delay glasses or amblyopia treatment that do help.

“Strabismus surgery is only cosmetic, so testing adults is pointless.” Adults with strabismus may have double vision, restricted visual fields and difficulty with eye contact, and a new turn can signal a neurological or thyroid problem. Measurement is the first step to understanding which applies.

“Crossed eyes in a photo means a diagnosis.” Pseudostrabismus caused by a wide nasal bridge is extremely common in infants, and the Hirschberg test separates it from true strabismus in seconds. Photos are a reason to book an exam, not a substitute for one.

The thread running through all of these is the same: alignment is a measurement, and measurements need to be taken, not assumed.

Questions to ask your care team after strabismus eye exam tests

Leaving the clinic with the right questions answered makes the following months far less anxious. These are the ones experienced families and patients tend to wish they had asked.

• What type of strabismus was found, which direction does the eye turn, and is it constant or intermittent?
• How large is the deviation in prism diopters, and did it differ between distance and near?
• Is the vision equal in the two eyes, and if not, is amblyopia present and what is the plan for it?
• Was significant farsightedness or other refractive error found, and are glasses expected to change the alignment?
• Did the dilated examination show a healthy retina and optic nerve in both eyes?
• Are there any features suggesting a muscle, nerve or thyroid problem that need further tests?
• What will be measured again at the next visit, and when should that visit be?
• What changes at home should prompt an earlier appointment?
• If surgery is ever considered, what would it aim to achieve, and what are the alternatives, including observation, glasses, prisms or patching?
• Who is the point of contact if a question comes up between visits?

Writing the prism diopter figure and the vision in each eye in a notebook is worth doing. Those two numbers are the baseline against which every future visit is judged, and having them to hand is helpful if care ever moves between clinicians.

A team that has measured carefully will welcome these questions. The answers should be specific, and where evidence is uncertain, for instance about whether an intermittent turn will progress, a good clinician will say so rather than promise an outcome.

When to call your doctor

Most strabismus is assessed at a booked appointment, and the majority of childhood squints are not emergencies. A small number of situations should not wait, because the eye turn may be a sign of something affecting the brain, nerves or the eye itself.

Contact your doctor or eye clinic promptly, the same day where possible, if any of the following occur:

• A new eye turn or new double vision in an adult, or in a child old enough to describe it.
• An eye turn that appears suddenly at any age, especially after a head injury or a recent illness.
• Double vision accompanied by headache, vomiting, weakness, numbness, difficulty speaking or unsteadiness. Seek emergency care for this combination, as MedlinePlus and Mayo Clinic advise for possible stroke or raised pressure in the head.
• A drooping eyelid alongside the turn, or a pupil that looks larger or smaller than the other.
• An eye that cannot move fully in one direction, or pain with eye movement.
• A white or absent reflection in one pupil in photographs, or a visibly cloudy pupil, which need urgent examination of the back of the eye.
• A baby whose eyes are constantly turned, whose eyes wobble, or who does not appear to fix on or follow faces by the age the NHS expects, around 3 months.
• A child who develops a persistent new head tilt or turn.

Between routine visits, call if a turn that was intermittent becomes constant, if a child begins closing one eye, or if vision in the weaker eye seems to be slipping despite glasses or patching. These are reasons to move the next appointment forward rather than wait for it.

Every decision about testing, treatment and timing rests with the treating team, who can weigh the whole picture. This article explains what the tests are for; it does not replace them.

Frequently asked questions

What test confirms strabismus?

The cover test confirms strabismus. The examiner covers one eye while the patient looks at a target and watches the uncovered eye; if it moves to pick up the target, it was misaligned. The direction of that movement shows whether the eye turns inward or outward. A prism cover test then measures the size of the deviation, and a light reflex test, motility check and dilated exam complete the assessment.

What is the gold standard test for strabismus?

The prism cover test performed by an experienced examiner is regarded as the reference measurement for strabismus. It combines the alternate cover test with prisms of increasing strength until the eye no longer moves, giving the deviation in prism diopters. No scan or automated device replaces it; imaging is used only to look for underlying causes when the history or exam suggests a nerve, muscle or structural problem.

Should I see an optometrist or an ophthalmologist for strabismus?

Either can perform the initial tests, and many pathways involve both. An optometrist can detect a turn, measure alignment and prescribe glasses, and is well placed for routine checks. A constant turn in a young child, a suspected difference in vision between the eyes, new double vision in an adult, or any question of surgery is usually referred to an ophthalmologist with pediatric or strabismus expertise, often working alongside an orthoptist.

What are the early warning signs of strabismus?

The earliest clue is usually an eye that looks turned, constantly or when the child is tired, plus light reflections sitting in different places on each pupil in photographs. Some children tilt or turn the head, close one eye in bright light, or lose their place when reading. Adults typically notice double vision. These observations are reasons to arrange an examination, not a diagnosis, and the NHS advises checking any squint seen after 3 months of age.

How does the cover test for strabismus tell a phoria from a tropia?

The cover-uncover test, which covers one eye and watches the other, detects a tropia: a turn present when both eyes are open. The alternate cover test, which swings the occluder between the eyes without ever allowing both to see the target, breaks fusion and reveals a phoria: a latent tendency to drift that the brain normally controls. Most people have a small phoria and never notice it; a tropia is what clinicians mean by strabismus.

What does a prism diopter measurement mean?

A prism diopter is the unit used to record the size of an eye turn. One prism diopter bends light so that an image shifts one centimeter at a distance of one meter. During the prism cover test, the examiner adds prisms until the eye stops moving to refixate, and that prism strength is the deviation. The number provides a baseline for follow-up and is the figure used to plan any eye muscle surgery.

What is the Hirschberg test and can it be done on a baby?

The Hirschberg test shines a small light toward the eyes and compares where the reflection sits on each cornea. Symmetric reflections suggest alignment; a displaced reflection suggests a turn in the opposite direction. It needs no cooperation beyond a brief glance, so it works well in infants. It is an estimate rather than a precise measurement, and it is especially useful for distinguishing true strabismus from pseudostrabismus caused by facial features.

Why do strabismus eye exam tests include dilating drops?

Dilating and cycloplegic drops temporarily relax the eye’s focusing muscle and widen the pupil. This lets the examiner measure the true refractive error, which matters because hidden farsightedness is a common driver of inward turning in children. The wide pupil also allows a direct view of the retina and optic nerve to rule out a structural cause for the turn. Blurred near vision and light sensitivity usually last several hours afterward, according to Mayo Clinic.

Can strabismus be diagnosed from a photograph?

No. Photographs can raise a reasonable concern, particularly when the light reflection appears in different positions on each pupil, but they cannot confirm strabismus. Camera angle, a wide nasal bridge and skin folds at the inner corners of a young child’s eyes frequently produce pseudostrabismus, an appearance of crossing with normal alignment. A photo is a good reason to book an eye alignment test, where the cover test settles the question.

How often are eye alignment tests repeated after diagnosis?

The interval is set by the treating team and depends on what was found. A child newly prescribed glasses for accommodative esotropia is often reviewed after a period of full-time wear to remeasure the turn with the glasses on. Children being treated for amblyopia are seen regularly to monitor vision in each eye. Small, stable, intermittent deviations may be measured at longer intervals. Any change noticed at home is a reason to bring the next visit forward.

References

• MedlinePlus: Strabismus
• NHS: Squint
• Cleveland Clinic: Strabismus (Crossed Eyes)
• National Eye Institute (NIH): Amblyopia (Lazy Eye)

This article is for general information only and is not a substitute for professional medical advice. Please consult a qualified doctor about your individual situation.