Strabismus

Strabismus (Crossed Eyes): Symptoms, Causes, Types, Diagnosis, and Treatments

Strabismus, commonly referred to as “crossed eyes,” is a vision disorder in which the eyes do not align properly. One eye may turn inward, outward, upward, or downward while the other focuses correctly. This misalignment can be constant or intermittent and may affect one or both eyes. Strabismus is more than a cosmetic issue—it can lead to serious vision problems if left untreated.

In this comprehensive guide, we will explore the symptoms, causes, types, diagnostic methods, and treatment options available for strabismus. Understanding this condition is crucial for early intervention, especially in children, where timely treatment can prevent lifelong visual impairments.

---

What is Strabismus?

Strabismus is a condition where the eyes do not work together in a coordinated way. Each eye has six muscles controlling its movement. When these muscles don’t work together properly, it causes the eyes to misalign. The brain receives two different visual signals, which can result in double vision or suppression of one image by the brain, potentially leading to amblyopia (lazy eye).

Strabismus affects people of all ages, but it most commonly presents in infants and young children. However, it can also occur in adults due to medical conditions or trauma.

---

Symptoms of Strabismus

The signs and symptoms of strabismus may vary depending on the severity and the type of misalignment. Common symptoms include:

In Children:

• Eyes that do not move together
• Frequent squinting or closing of one eye
• Tilting or turning the head to see clearly
• Uncoordinated eye movements
• Complaints of double vision (in older children)
• Poor depth perception
• Eye strain or fatigue
• A noticeable turn in one eye (inward, outward, upward, or downward)

In Adults:

• Sudden onset of double vision
• Difficulty reading or focusing
• Eye strain or headaches
• Inability to align eyes when looking in certain directions

Strabismus in adults can significantly impact quality of life, making everyday tasks like reading, driving, or walking difficult due to visual disturbances.

---

Causes of Strabismus

Strabismus can be caused by a variety of factors, and in some cases, the cause is unknown (idiopathic). Understanding the underlying cause is essential for effective treatment.

1. Genetic Factors

Strabismus can run in families. A child with a parent or sibling who has strabismus is more likely to develop it.

2. Neurological Conditions

Issues in the brain that control eye movement, such as cerebral palsy, Down syndrome, hydrocephalus, or stroke, can cause strabismus.

3. Refractive Errors

Uncorrected farsightedness (hyperopia) can lead to accommodative strabismus, where the extra effort needed to focus causes eye misalignment.

4. Eye Muscle Problems

Abnormalities in the eye muscles or the nerves that control them can lead to misalignment.

5. Trauma or Injury

Head injuries, especially those affecting the brain or the eye muscles, can result in strabismus.

6. Vision Loss in One Eye

When one eye has significantly reduced vision, the brain may stop trying to align it, leading to strabismus.

7. Tumors

Orbital or brain tumors affecting eye movement centers or optic nerves can also cause strabismus.

---

Types of Strabismus

Strabismus is classified based on the direction of eye misalignment, consistency, and the underlying cause. The main types include:

1. Esotropia (Inward Turning of the Eye)

• The most common form in children.
• May be constant or intermittent.
• Can be congenital or develop in early childhood.

2. Exotropia (Outward Turning of the Eye)

• Common in both children and adults.
• Often intermittent at first, especially when the person is tired or focusing on distant objects.
• May worsen over time.

3. Hypertropia (Upward Turning of the Eye)

• One eye turns higher than the other.
• Often due to muscle imbalance or nerve palsy.

4. Hypotropia (Downward Turning of the Eye)

• One eye turns downward compared to the other.
• Less common and often linked to trauma or neurological issues.

5. Accommodative Strabismus

• Related to uncorrected farsightedness.
• The eyes turn inward when trying to focus.

6. Paralytic Strabismus

• Caused by nerve damage or muscle paralysis.
• Often results in sudden onset double vision.

7. Intermittent Strabismus

• The eye misalignment occurs occasionally.
• May happen when the person is tired, ill, or daydreaming.

8. Constant Strabismus

• The eye misalignment is always present.
• Higher risk of developing amblyopia.

---

Diagnosis of Strabismus

Early diagnosis of strabismus is crucial to prevent long-term visual complications. An eye care professional—typically an optometrist or ophthalmologist—performs a series of exams to confirm the diagnosis.

1. Medical History

• Family history of strabismus
• Duration and onset of symptoms
• Presence of any other neurological or systemic conditions

2. Visual Acuity Test

• Measures how well each eye sees.

3. Refraction Test

• Detects refractive errors such as nearsightedness, farsightedness, or astigmatism.

4. Ocular Alignment Tests

• Cover-uncover test
• Hirschberg test (corneal light reflex)
• Alternate cover test
  These tests help determine the degree and direction of the eye misalignment.

5. Dilated Eye Exam

• Checks the health of the internal structures of the eye.

6. Binocular Vision Tests

• Assesses how well the eyes work together.

7. Imaging Tests (If Needed)

• MRI or CT scan may be ordered if a tumor, trauma, or neurological condition is suspected.

---

Treatment of Strabismus

The goal of treatment is to align the eyes, restore binocular vision, and prevent or treat amblyopia. The appropriate therapy depends on the type, cause, and severity of the condition.

1. Glasses or Contact Lenses

Correcting refractive errors can often improve or eliminate strabismus, particularly accommodative types.

• Benefits:
  • Non-invasive
  • May correct the problem without further intervention

2. Prism Lenses

Special lenses that help reduce double vision by redirecting light to assist in alignment.

• Common in:
  • Adults with small-angle strabismus
  • Post-stroke patients

3. Vision Therapy

Structured eye exercises performed under professional supervision to improve coordination and strengthen eye muscles.

• Effective for:
  • Intermittent strabismus
  • Convergence insufficiency

4. Eye Patching

Patching the stronger eye helps strengthen the weaker one, especially useful in amblyopia treatment.

• Duration:
  • Hours per day over weeks or months

5. Botox Injections

Botulinum toxin may be injected into specific eye muscles to temporarily weaken them, allowing the eyes to realign.

• Benefits:
  • Non-surgical option
  • Useful in some adult cases or trial before surgery

6. Surgery

Surgical intervention may be necessary if other methods are ineffective. It involves adjusting the length or position of the eye muscles to align the eyes properly.

• Types of Surgery:
  • Recession (loosening a muscle)
  • Resection (tightening a muscle)
  • Adjustable suture surgery
• Success Rate:
  • High success when performed by experienced surgeons
  • May require more than one surgery

7. Treatment of Underlying Conditions

If strabismus is secondary to another condition (e.g., a tumor or thyroid eye disease), addressing that root cause is essential.

---

Prognosis and Long-Term Management

The prognosis for strabismus varies. With early detection and appropriate treatment, many individuals—especially children—can achieve normal or near-normal vision.

In Children:

• Best outcomes when treated before the age of 6
• Regular follow-ups to monitor eye alignment and vision
• Lifelong management may be necessary in some cases

In Adults:

• Improvement depends on cause and duration
• May not fully restore binocular vision
• Visual rehabilitation may be required

Preventing Recurrence:

• Routine eye exams
• Timely prescription updates for glasses
• Adherence to vision therapy or patching schedules

---

Living with Strabismus

Strabismus can impact more than just vision. It can also affect self-esteem, social interaction, and academic or job performance.

Coping Strategies:

• Educate family and teachers about the condition
• Consider counseling or support groups
• Work with occupational therapists if motor skills are affected

Myths and Misconceptions:

• Myth: Children will outgrow crossed eyes.
  • Fact: Strabismus rarely corrects itself and usually needs treatment.
• Myth: Strabismus is just a cosmetic issue.
  • Fact: Untreated, it can lead to serious visual impairment and depth perception issues.

---

When to See a Doctor

Seek medical attention if:

• You notice misalignment of the eyes
• Your child tilts their head frequently
• There’s a sudden change in vision
• Double vision appears
• The eyes seem to wander or not focus together

Early evaluation can lead to effective intervention and prevent complications.

---

Conclusion

Strabismus is a common yet complex eye condition that demands early diagnosis and appropriate treatment to ensure optimal visual outcomes. Whether in children or adults, ignoring the signs of strabismus can result in permanent vision problems, including amblyopia and loss of binocular vision.

Fortunately, modern advancements in diagnostics and treatment offer a wide range of options—from corrective lenses and vision therapy to surgical solutions. With proper care, most individuals with strabismus can lead normal, visually comfortable lives.

If you or a loved one shows signs of strabismus, consult an eye care professional promptly. A timely and tailored treatment plan can make a world of difference in preserving and improving vision.

Frequently Asked Questions (FAQs) About Strabismus (Crossed Eyes)

For more details keep visiting our Website & Facebook Page.