Conditions / Strabismus & Double Vision

Strabismus & Double Vision

When the eyes stop pointing at the same thing — whether the drift has been there since childhood or the double image appeared this week — it is worth having assessed. In children, early alignment protects vision for life. In adults, sudden new double vision can be a sign that needs urgent attention.

Book a consultation What is strabismus? →

Common symptoms

Signs of strabismus in children and adults

Book a consultation if your child's eyes drift, turn inward, outward, up or down.

One eye turns inward toward the nose

One eye drifts outward away from center

Your child tilts or turns their head to see

Double vision or overlapping images

Squinting or closing one eye in bright light

Eyes that do not move together

Poor depth perception or bumping into things

Eye strain or headaches after focusing

What is strabismus?

Double vision — diplopia — is what happens when suppression is not in place. The classic distinction is binocular versus monocular. Binocular double vision comes from misalignment: cover either eye and the second image disappears. Monocular double vision persists in one eye even with the other covered, and usually points to something in the cornea or lens rather than the alignment system. New binocular double vision in an adult is treated as a red flag until proven otherwise — nerve palsies, thyroid eye disease, myasthenia and stroke can all present this way, and same-day assessment matters.

Why strabismus and diplopia get missed

Intermittent deviations hide during a quick look, and a child rarely complains

A small-angle or intermittent strabismus can be invisible for most of the day. It shows itself when the child is tired at bedtime, unwell with a fever, or fixed on a screen — and by the time you look again the eyes are back in line. Children very seldom mention double vision, because the brain has often already learned to suppress the second image. Adults, by contrast, cannot suppress an eye that has been aligned for decades — so new adult misalignment usually announces itself as diplopia rather than as a visible turn.

Small-angle deviations look normal at a glance — a cover test is what reveals them
A well-compensated phoria can pass a rushed screening; symptoms only appear when the ability to hold alignment breaks down
Adult-onset diplopia is sometimes attributed to tiredness or a new spectacle prescription, when the underlying cause is a cranial nerve palsy that needs imaging

Signs it's worth a specialist consultation

Strabismus in a young child and new-onset diplopia in an adult are both situations where earlier is better. The threshold for booking an assessment is low — if any of the following sound familiar, it is worth a visit.

An eye that turns in, out, up or down — even briefly, even only sometimes

Source: American Academy of Ophthalmology

A head tilt, face turn or chin lift that has appeared or worsened

Source: American Association for Pediatric Ophthalmology and Strabismus

A family member has strabismus, amblyopia, or wore a patch as a child

Source: International Council of Ophthalmology

Sudden new double vision, especially with headache, weakness, or after a head injury

Source: British and Irish Orthoptic Society

A school screening or driving assessment flagged the eyes are not working together

Source: American Orthoptic Council

A child who covers or closes one eye to see clearly at distance or up close

Source: World Society of Paediatric Ophthalmology and Strabismus

Book a Consultation

New adult diplopia is urgent. Childhood strabismus is time-sensitive.

Sudden binocular double vision in an adult can be the first sign of a cranial nerve palsy, thyroid eye disease, myasthenia gravis or stroke — same-day assessment is the safer default. In children, an untreated turning eye can drive amblyopia within months, and the visual brain's window to recover closes by around age eight. Both scenarios reward being seen sooner rather than later.

Book a consultation Alignment & Binocular Vision

How our doctors approach strabismus and diplopia

A strabismus and diplopia assessment is built around a few essentials. Visual acuity is measured eye-by-eye. Cover and alternate-cover testing, with prism neutralisation, quantifies the size and direction of the deviation at distance and near. Ocular motility is checked in the nine positions of gaze to catch a nerve palsy or restrictive pattern. In children, a cycloplegic refraction — using drops to relax the focusing muscle — is essential, because uncorrected long-sightedness is one of the most common drivers of accommodative esotropia. In adults with new diplopia, the history and pattern of the deviation guide whether imaging or a medical workup is needed the same day.

Cover / prism cover test — direction and size of the deviation at distance and near
Ocular motility in the nine positions — to detect a nerve palsy or restriction
Visual acuity and cycloplegic refraction — the true prescription, each eye in turn
Dilated fundus examination — to exclude a structural or neurological cause

What treatment looks like

Glasses and prisms first — surgery only if it is the right tool

Glasses first — correct the refractive error, especially in accommodative esotropia
Prisms — ground into the lens for stable small deviations that cause diplopia
Orthoptic exercises — for convergence insufficiency and select intermittent exotropias
Surgery referral — coordinated for larger or long-standing misalignments

Your consultation

What the visit looks like

A first strabismus or diplopia assessment is thorough. A second short visit after cycloplegia is sometimes useful in children to confirm the prescription.

Settling in

Time to feel comfortable in the room. For children we start with simple, unintimidating tasks — matching pictures, following a small toy — before any equipment comes near. For adults, we walk through the history in detail: when it started, what makes it better or worse.

Alignment testing

Visual acuity each eye in turn, cover and prism cover testing at distance and near, ocular motility in the nine positions of gaze, and — in children or where indicated — a cycloplegic refraction and dilated fundus examination.

Findings explained

The doctor walks you through what was seen, in language you can follow. Diagrams on screen, with the imaging and prism measurements open, so the type and size of the deviation are clear.

Plan together

A written plan — glasses, prisms, patching or orthoptic exercises, and where relevant a referral for surgical realignment — with the date of the next review. Most plans are reassessed every six to twelve weeks.

Meet your specialist

Care led by specialists you'll meet in person.

Lead Ophthalmologist · Cataract and Retina Surgeon

Dr. JD Ferwerda, MD

Dr. JD Ferwerda, MD: Dutch-trained ophthalmologist specialising in cataracts, lens exchange, retinal disease, glaucoma, and AMD.

Book with Dr. JD See profile →

Refractive Surgeon

Dr. Artem Kozhechenkov, MD

Russian-trained refractive and general ophthalmologist, leads lasik/ laser vision correction at EEC

Book with Dr. Artem See profile →

If something's been off — bring them in.

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