Strabismus (often called “crossed eyes” or “wall eyes”) is a common eye condition where the eyes fail to align properly, preventing both from focusing on the same object. For many, it’s a source of frustration—impacting vision, self - esteem, and daily life. The good news? Early diagnosis and treatment can restore alignment and preserve binocular vision (the ability to see depth and single images). Below, we break down what strabismus is, why it happens, how it’s classified, and how to treat it.
Strabismus occurs when the extraocular muscles (the muscles that control eye movement) don’t coordinate correctly. One eye fixates on a target, while the other drifts inward, outward, upward, or downward. This misalignment can be constant (always visible) or intermittent (only appearing in certain situations, like tiredness or stress).
Strabismus is either congenital (present at birth or within 6 months) or acquired (develops later in life). Common triggers include:
- Genetic factors: Family history of strabismus increases risk.
- Neuromuscular issues: Damage to eye muscles, nerves (e.g., cranial nerves III, IV, or VI), or the brain (from stroke, trauma, or conditions like cerebral palsy).
- Refractive errors: Uncorrected farsightedness (hyperopia) or nearsightedness (myopia) can cause eye strain and misalignment.
- Medical conditions: Thyroid eye disease, diabetes, or autoimmune disorders may restrict eye movement.
Strabismus is grouped by four key factors—each helping doctors tailor treatment:
- Concomitant (Non - Paralytic) Strabismus: Eye muscles work normally, but alignment is off. Misalignment stays consistent no matter which direction you look.
- Non - Concomitant (Paralytic/Restrictive) Strabismus: Eye movement is limited. Misalignment worsens when looking in certain directions.
- Paralytic: Caused by nerve/muscle damage (e.g., a paralyzed superior rectus muscle makes it hard to look up).
- Restrictive: Mechanical issues (e.g., thyroid eye disease thickens eye muscles, pulling the eye out of place).
- Congenital Strabismus: Present at birth or within 6 months. Most often inward - turning (esotropia) or outward - turning (exotropia).
- Acquired Strabismus: Develops after 6 months—often from injury, illness, or uncorrected vision problems.
- Horizontal: Inward (esotropia) or outward (exotropia) turn.
- Vertical: Upward (hypertropia) or downward (hypotropia) drift.
- Rotational: Eye twists inward (incyclotropia) or outward (excyclotropia).
- Mixed: Combines horizontal, vertical, or rotational misalignment.
- Latent Strabismus (Phoria): Eyes tend to misalign, but the brain corrects it to keep vision clear. Misalignment only appears when one eye is covered.
- Manifest Strabismus (Tropia): Eyes are clearly misaligned—brain can’t fix it.
- Constant: Permanent misalignment.
- Intermittent: Misalignment comes and goes (e.g., when tired or focusing on distant objects).
Two of the most prevalent forms are accommodative esotropia and exotropia:
This inward - turning strabismus is caused by uncorrected hyperopia (farsightedness). To focus on close objects, the eyes overwork (over - accommodate), leading to over - convergence (inward turning). If the brain can’t counteract this, esotropia develops.
- Fully Accommodative: Correcting hyperopia with glasses fixes alignment entirely.
- Partially Accommodative: Glasses reduce—but don’t eliminate—misalignment. Surgery may be needed for residual strabismus.
Exotropia is an outward eye turn (away from the nose). It’s less common than esotropia (1 in 3 strabismus cases) and often starts as intermittent (e.g., when daydreaming or looking far away). Types include:
- Convergence Insufficiency: Worse when focusing on close objects (e.g., reading).
- Basic Exotropia: Equal misalignment for near and far vision.
- Abduction Excess: Worse when looking far away (rare).
The goal is to restore binocular vision (depth perception) and align eyes. Early intervention (before age 7) is critical—younger brains adapt better!
- Glasses/Prism Lenses: Mild strabismus or hyperopia - related cases can be fixed with special lenses that redirect light to align eyes.
- Amblyopia (Lazy Eye) Therapy: If strabismus causes one eye to be weaker (amblyopia), patching the strong eye or using eye drops first helps strengthen the lazy eye.
- Orthoptic Training: Eye exercises to improve coordination (e.g., tracking moving objects). Works best as a complement to glasses or surgery.
If non - surgical methods fail, extraocular muscle surgery adjusts eye muscles to correct alignment. Here’s what to expect:
- Procedure: Surgeons weaken (recess) or strengthen (resect) muscles to rebalance eye movement.
- Recovery: Minor discomfort (managed with pain relievers) and temporary double vision (fades in days/weeks).
- Post - Surgery: Vision therapy often follows to strengthen binocular vision.
- Early Treatment = Better Outcomes: The sooner you act (especially for kids), the higher the chance of restoring normal vision.
- No One - Size - Fits - All: Treatment depends on type, severity, and age—work with an ophthalmologist to create a plan.
- Surgery Is Safe: Modern techniques have high success rates (80–90% for simple cases) and minimal risk.
Strabismus doesn’t have to impact your quality of life. With the right diagnosis and care, most people can achieve aligned eyes and clear vision. If you or your child has signs of strabismus (crossed eyes, double vision, or frequent eye rubbing), schedule an eye exam today.
