Strabismus: Crossed Eyes, Double Vision, and Treatment

Strabismus is a condition in which the eyes do not point in the same direction at the same time. Early diagnosis and individualized treatment can support comfortable vision, eye teamwork, and healthy visual development.

Overview

Strabismus is an eye alignment disorder in which the two eyes do not look at the same object at the same time. One eye may turn inward, outward, upward, or downward while the other eye focuses straight ahead. The condition is commonly described as crossed eyes, wandering eye, squint, or eye turn.

Eye alignment depends on the coordinated action of six muscles around each eye, the nerves that control them, and the brain areas that help the eyes work as a team. When this coordination is disrupted, the brain receives two images that do not match. In adults this may cause double vision, while in young children the brain may ignore the image from the misaligned eye to avoid confusion.

Strabismus can be constant or intermittent. It may be present from infancy, appear during childhood, or develop later in life. Some cases are mild and noticeable only when a person is tired, ill, or focusing at a distance or near. Others are more obvious and may affect depth perception, reading comfort, balance, self-confidence, and daily activities.

Types and Symptoms

The direction of the eye turn helps describe the type of strabismus. Esotropia means one eye turns inward toward the nose. Exotropia means one eye turns outward. Hypertropia and hypotropia describe an eye that is higher or lower than the other. Some people have a combination of horizontal and vertical misalignment, or a pattern that changes depending on gaze direction.

Symptoms vary by age and by how suddenly the misalignment appears. Children may not complain of double vision because their developing brain can suppress, or turn off, the image from one eye. Adults are more likely to notice double vision, eye strain, headaches, or difficulty judging distance.

• Visible eye crossing or drifting
• Double vision or overlapping images
• Closing or covering one eye, especially in bright light
• Tilting or turning the head to see more clearly
• Poor depth perception or clumsiness with stairs and sports
• Eye fatigue, reading discomfort, or headaches
• In children, reduced vision in one eye due to amblyopia, also called lazy eye

Intermittent symptoms are still important. An eye that drifts only occasionally can become more frequent over time, and a child who adapts well may still need an eye examination to protect visual development.

Causes and Risk Factors

Strabismus may occur when the eye muscles, the nerves controlling those muscles, or the brain mechanisms that coordinate binocular vision do not work together smoothly. In many children, no single cause is found. The condition may be related to refractive errors such as farsightedness, differences in vision between the two eyes, family tendency, or developmental factors.

Some children develop accommodative esotropia, in which significant farsightedness leads the eyes to turn inward when focusing. In these cases, properly prescribed glasses may greatly improve alignment. Other children may have strabismus associated with prematurity, cerebral palsy, Down syndrome, neurological conditions, or a history of significant eye disease.

In adults, new strabismus can occur for different reasons. These include thyroid eye disease, diabetes-related nerve palsy, stroke, head injury, myasthenia gravis, orbital inflammation or tumors, previous eye surgery, or decompensation of a childhood eye alignment problem that had been well controlled. Not every cause is serious, but a careful evaluation is needed, especially when double vision begins suddenly.

Risk factors include a family history of strabismus or amblyopia, high refractive error, poor vision in one eye, premature birth, certain genetic or neurological conditions, and previous eye trauma. Regular childhood vision screening and comprehensive eye examinations help identify children who need treatment early.

Diagnosis

Diagnosis begins with a detailed history. The eye specialist asks when the eye turn started, whether it is constant or intermittent, which eye turns, whether double vision is present, and whether there are headaches, neurological symptoms, trauma, or general health conditions. In children, information from parents or caregivers is especially valuable because symptoms may not be reported clearly.

A comprehensive eye examination usually includes measurement of visual acuity, assessment of glasses prescription, eye alignment tests, eye movement evaluation, and examination of the front and back of the eyes. The cover test is commonly used to observe how each eye moves when one eye is covered and uncovered. Special prisms may help measure the angle of deviation.

The doctor may also check depth perception, focusing ability, pupil reactions, eyelid position, and signs of amblyopia. Dilating eye drops are often used in children to measure refractive error accurately and examine the retina and optic nerve. These drops temporarily blur near vision and increase light sensitivity, which is expected and wears off.

If strabismus develops suddenly in an adult, or if the examination suggests nerve, muscle, or brain involvement, further testing may be recommended. This can include blood tests, neurological assessment, or imaging such as MRI or CT, depending on the clinical findings. The goal is to identify both the eye alignment problem and any underlying condition that needs attention.

Treatment Options

Treatment for strabismus is individualized. The goals may include improving eye alignment, protecting or improving vision in each eye, restoring or supporting binocular vision, reducing double vision, and improving comfort and function. The best approach depends on the person’s age, the type and size of the eye turn, visual acuity, refractive error, symptoms, and underlying cause.

Glasses or contact lenses may be the first step when a refractive error contributes to the misalignment. In accommodative esotropia, glasses can reduce the focusing effort that triggers the inward eye turn. Prism lenses may help some people with double vision by shifting the image so the eyes can work together more comfortably, especially when the deviation is small or stable.

If amblyopia is present, treatment may involve patching the stronger eye or using special drops or optical methods to encourage use of the weaker eye. This is most effective in childhood, when the visual system is still developing. Vision therapy or orthoptic exercises may be helpful in selected conditions, such as convergence insufficiency, but they are not the correct treatment for every form of strabismus.

Botulinum toxin injections may be considered in certain cases to temporarily weaken an overacting eye muscle and improve alignment. Eye muscle surgery is another established treatment. During surgery, the ophthalmologist adjusts the position or tension of one or more eye muscles to improve alignment. Surgery does not remove the eye from the socket, and it is performed with careful planning based on measurements. Some people need more than one procedure over time, especially if the condition changes with growth or healing.

Prevention and Self-Care

Not all cases of strabismus can be prevented, especially those related to early development, genetics, or neurological causes. However, timely detection can prevent complications such as amblyopia and may improve the chance of comfortable binocular vision. Parents should follow recommended pediatric vision screening schedules and seek an eye examination if they notice persistent eye crossing, drifting, or unusual head posture.

For children who are prescribed glasses, patches, or other treatment, consistency is important. Caregivers can help by making glasses part of the daily routine, offering positive encouragement during patching, and attending follow-up visits so the treatment plan can be adjusted. If a child refuses glasses or patching, the family should discuss practical strategies with the eye care team rather than stopping treatment without guidance.

Adults with strabismus can support comfort by using prescribed lenses correctly, taking breaks during prolonged screen use, and avoiding driving or hazardous tasks when double vision is not controlled. Covering one eye can temporarily reduce double vision in some situations, but it is not a substitute for medical evaluation. New or changing symptoms should always be discussed with a qualified clinician.

Good general health also supports eye and nerve function. Managing diabetes, thyroid disease, blood pressure, and other chronic conditions as advised by a doctor can reduce the risk of some acquired eye movement problems. Protective eyewear during sports or high-risk work can help prevent eye and orbital injuries.

When to See a Doctor

An eye examination is recommended if a child’s eyes appear misaligned after the first few months of life, if an eye turn is frequent or worsening, or if the child closes one eye, tilts the head, bumps into objects, or seems to have reduced vision. Occasional brief misalignment can occur in very young infants, but persistent or recurrent crossing should be evaluated by a pediatric ophthalmologist or an eye specialist experienced in children’s eye care.

Adults should seek prompt medical assessment for new double vision, sudden eye misalignment, drooping eyelid, unequal pupils, eye pain, headache with neurological symptoms, weakness, numbness, trouble speaking, or symptoms after head trauma. These signs do not always indicate a serious condition, but they need appropriate evaluation to determine the cause.

Follow-up is also important after diagnosis. Strabismus can change over time, especially as a child grows or after treatment begins. Regular visits allow the doctor to monitor visual acuity, eye alignment, glasses prescription, amblyopia treatment response, and whether surgery or another intervention should be considered.

For international patients seeking coordinated evaluation, Acibadem International’s multidisciplinary specialists and JCI-accredited hospitals diagnose and treat strabismus and related eye conditions. Patients should bring previous eye reports, glasses prescriptions, imaging results, and a list of medical conditions or medications to support an efficient consultation.

Frequently asked questions

Is strabismus the same as lazy eye?

No. Strabismus means the eyes are misaligned, while lazy eye, medically called amblyopia, means one eye has reduced vision because the brain did not develop normal visual input from that eye. Strabismus can cause amblyopia in children, but they are different conditions. A child may need treatment for both alignment and visual development.

Can a baby outgrow crossed eyes?

Very young infants may have occasional brief eye misalignment while visual coordination is developing. However, persistent crossing, frequent drifting, or an eye turn that continues after the early months should be checked by an eye specialist. Early evaluation is important because children may not show obvious symptoms even when vision is affected.

Why does strabismus cause double vision in adults?

When the eyes point in different directions, each eye sends a different image to the brain. Adults have an established visual system, so the brain often perceives both images, resulting in double vision. Children may suppress one image, which reduces double vision but can interfere with normal visual development.

Will glasses fix strabismus?

Glasses can correct strabismus in some people, especially children with accommodative esotropia related to farsightedness. In other cases, glasses may improve vision but not fully align the eyes. Additional treatments such as patching, prisms, exercises for selected problems, injections, or surgery may be recommended.

Is strabismus surgery painful or risky?

Strabismus surgery is a common eye muscle procedure performed by trained ophthalmic surgeons, usually under anesthesia. Discomfort, redness, and irritation can occur during recovery, and all surgery has potential risks such as infection, undercorrection, overcorrection, or the need for further treatment. The surgeon explains the expected benefits and risks based on the individual case.

Can adults be treated for strabismus?

Yes. Adults can benefit from treatment to reduce double vision, improve eye alignment, expand comfortable gaze positions, or address appearance-related concerns. Treatment may include prisms, management of an underlying medical condition, botulinum toxin, or eye muscle surgery. A full evaluation helps determine the most suitable option.

When is double vision an urgent symptom?

New or sudden double vision should be assessed promptly, especially if it occurs with severe headache, eye pain, drooping eyelid, unequal pupils, weakness, numbness, speech difficulty, dizziness, or recent head injury. These symptoms may require urgent medical evaluation. If double vision is intermittent but recurring, an eye examination is still recommended.

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.