Choose the content to read

• Why strabismus surgery?
• What are the types of strabismus?
• What causes strabismus?
• What are the symptoms of strabismus?
• What is the strabismus surgery procedure?
• What is the advantage of strabismus surgery?
• Strabismus surgery at MedPark Hospital

Strabismus surgery

Strabismus surgery, or eye muscle surgery, is the surgical correction of strabismus, squinting, or misaligned eyes, a condition in which both eyes do not focus on the same direction, by surgically correcting extraocular muscle to adjust the eyeball to be in the centered core and having the same vertical and horizontal vision direction. Strabismus surgery corrects eye muscle imbalances, extraocular muscle enlargement, or weak eye muscles due to congenital eye disease or central nervous system disease, while also assisting in preventing complications including blurred vision, double vision, or impaired vision. Strabismus, or eye misalignment, can be treated by having an eye examination and surgery with an expert ophthalmologist as soon as symptoms appear.

Why strabismus surgery?

Untreated strabismus or crossed eyes in a preschool child can cause blurry vision, double vision, and loss of 3D vision, eventually leading to "lazy eye" (amblyopia); the child starts using only one eye, and the brain will begin to suppress the image received from the deviated eye and eventually block the visual signal from the deviated eye.

Strabismus surgery, caused by muscle imbalances or extraocular muscle enlargement, treats blurred vision, double vision, and tired eyes, balances eye alignment, and preserves 3D vision.

What are the types of strabismus?

• Esotropia (Horizontal inward type) is a strabismus in which one or both eyes move toward the inner corner of the eye or the nose. Esotropia is found in infants aged 4 months and above, known as infantile esotropia.
• Exotropia (Horizontal outward type) is a strabismus in which one or both eyes move toward the outer corners of the eyes. Exotropia is frequently associated with nearsightedness due to some eye diseases such as cloudy lenses (lens opacity), vitreous degeneration, retina disease caused by a black eye scar from a foreign object thrown into the eye, accident, or macular degeneration.
• Hypertropia (Vertical upward type) is a strabismus in which one eye looks straight while the other squints upwards due to extraocular muscle abnormalities.
• Hypotropia (Vertical downward type) is a strabismus in which one eye looks straight while the other squints downward due to extraocular muscle abnormalities, resulting in the eyeball drooping downwards.
• Torsional is a strabismus in which the eyes rotate inwards or outwards.
• Phoria is a latent strabismus, a type of strabismus in which the eye's position is in the center when both eyes are open but deviates from the center when one is covered. Conversely, if it uncovers that eye, it will return to the center position. Phoria often results in eye fatigue.
• Pseudostrabismus is an anatomical feature of some children's faces that makes it appear as if the child has strabismus, but the child does not have abnormalities in the eye muscles or double vision. For example, the child has a broad nose bridge, or a large black eye closed to the inner corners of the eyes, giving the appearance of esotropia.

What causes strabismus?

There are 6 extraocular muscles in one eye that control the direction of eye movement: up and down, left and right in order to see things normally. Strabismus symptoms are caused by an abnormal structure of the extraocular muscles, such as extraocular muscle enlargement, which results in an imbalanced eye muscle, misaligned eye movement, and an inability to focus on objects in the same direction, resulting in strabismus, squinting, or phoria. Strabismus can also be caused by the following factors:

• Refractive errors: nearsightedness, farsightedness, and astigmatism. Esotropia is commonly found in children with moderate farsightedness due to the eye's need to be more focused on the object in order to see things more clearly. Refractive errors in children with nearsightedness or astigmatism can cause eye muscle imbalances, resulting in strabismus (squinting).
• Central nervous system disease: Normally, the central nervous system regulates and commands the extraocular muscles to function properly. If the central nervous system is impaired, the extraocular muscles become paralyzed, resulting in delayed physical and brain development. In addition, some diseases, such as cerebral palsy (due to paralysis of the 3rd, 4th, or 6th cranial nerves) or rubella, can also impair the central nervous system.
• Genetic: Strabismus caused by inheritance can result in abnormalities of the extraocular muscles, such as congenital fibrosis syndrome, Noonan syndrome, or Edward's syndrome.
• Eye disease: Unilateral eye diseases can cause blurred vision, macular degeneration, and imbalanced eye muscles, leading to strabismus, thyroid disease, meningitis, brain tumors, or cancer.
• Ocular trauma or severe brain damage caused by a traumatic skull fracture, broken eye socket, intracerebral hemorrhage, or stroke.

(LEFT) EXTROPIA  (RIGHT) NORMAL POSITION

What are the symptoms of strabismus?

• Both eyes do not look in the same direction, misaligned eyes.
• Both eyes do not move together and do not move synchronously in parallel.
• One eye squinted, closed, or frequently blinked when exposed to bright sunlight.
• Closing one eye when looking at objects or reading near or far characters or signs.
• Tilting neck, tilting head when looking at objects, a conversation partner, or something.
• Faulty vision, faulty depth perception, bumping into something.
• Headache, eye strain, difficulty reading, trouble reading, tired eyes.
• When a child grows older, the eye develops blurred vision, double vision, and a lazy eye.

What is the diagnosis before strabismus surgery?

The ophthalmologist will determine strabismus surgery to treat extraocular muscle enlargement and eye muscle imbalances, including strabismus, which is at high risk of binocular vision loss and cannot be treated with other treatment options. The ophthalmologist will diagnose strabismus using the following examinations:

• Medical history: Inquiring about the age at which strabismus appeared, whether there is a tilt of the head involved, a squirting eye on one side or alternating sides when looking near and far, or both, if there is a family history of strabismus, a medical history, and an accident history.
• Eye examination: Examine the retina, optic nerve, and blood vessels of the eye for signs of macular degeneration, corneal degeneration, glaucoma, diabetic retinopathy, or retinal cancer.
• Visual acuity: Measure eye level, check the vision for nearby and distant objects, and assess the clarity of the vision.
• Refraction: Check for refractive errors (nearsightedness, farsightedness, astigmatism), and check the eyesight.
• Light reflex testing entails looking directly at a light source, such as a flashlight, from about 1-3 feet away and checking for light reflection on the iris. Strabismus does not exist when the light falling on the iris is evenly distributed on both sides. Adversely, strabismus exists when the light falling on the iris is unevenly distributed on both sides.
• Cover testing entails gazing steadily at an object while covering one eye with paper. Strabismus exists when the covered eye moves while being covered.

What is the strabismus surgery procedure?

Strabismus surgery at MedPark Hospital adopts international standards, prioritizing the utmost safety and treatment success outcome. The surgery can be performed on young children aged 1 year and up as an outpatient surgery without requiring a hospital stay. The patient can go home after recovering from anesthesia, and the result of the overall physical evaluation by the ophthalmologist is satisfactory and found no serious complications.

• The anesthesiologist will administer light sedation and anesthesia to the patient before the surgery.
• The ophthalmologist will use a speculum to hold the eye open wide before surgery. The ophthalmologist will rotate the eyeball in a left-right, up-down direction to determine the location of the extraocular muscles to be operated on.
• The ophthalmologist performs strabismus surgery by surgically correcting extraocular muscles to adjust the eyeball to be in the centered core and by cutting a tiny surgical incision on the conjunctiva, or the white covering of the eye, to balance the length and the tension of the extraocular muscles.
• If the extraocular muscles are too slack, the ophthalmologist will excise some portion of the extraocular muscles to tighten the extraocular muscles. Adversely, if the extraocular muscles are too tight, the ophthalmologist will move the recession point deeper to the back from its original position to relax the extraocular muscles.
• When the position of the pupils is symmetrically aligned, the ophthalmologist will suture the surgical wound with stitches, apply eye drops, and cover the eye. Typically, the surgery takes approximately 30 minutes to 2 hours, depending on the complexity of the cases.

What is the postoperative care of strabismus surgery?

• The ophthalmologist will schedule a follow-up appointment the day after the surgery.
• Take medications as directed by the doctor to alleviate pain and inflammation that may occur.
• Avoid rubbing or squeezing your eyes and wear an eye shield while sleeping for 2 weeks to prevent accidental rubbing.
• Apply eye drops as directed by your doctor to prevent infection, inflammation, and irritation.
• Beware of water entering your eyes; refrain from washing your face for 2 weeks and swimming for 2-3 months.
• Avoid strenuous exercise and lifting heavy objects for 2 weeks.
• Attend every ophthalmologist appointment for symptom monitoring and post-operative evaluation.

What is the complication of strabismus surgery?

Strabismus surgery is a minor surgery and is regarded as a very safe procedure. The surgery has a high success rate of 80–90%, depending on the age, type of strabismus, and complexity. Postoperative complications of strabismus surgery include infection, hyphemia (bleeding in the eye), and double vision. However, the symptoms gradually improve and disappear. The ophthalmologist will recommend appropriate treatment suitable for individuals.

What is the advantage of strabismus surgery?

• Minor surgery, less painful, recovery quickly.
• Outpatient surgery: the wound heals quickly and restoring eyesight rapidly.
• Highly safe, low risk, low complications
• Treat double vision, tired eyes
• Prevent “lazy eye,” loss of 3D vision
• Less tissue damage, less blood loss
•  Improves personality and quality of life
• Eliminate life’s limitations and increase life’s opportunities.

Strabismus surgery at MedPark Hospital

Eye Center at MedPark Hospital in Bangkok, Thailand, is led by a team of seasoned ophthalmologists at the professor level with extensive experience in performing all types of strabismus surgery, both in children and adults, with the readiness to provide diagnostic and therapeutic interventions in treating common and complex eye diseases, anomalous extraocular muscles, or strabismus with detail-oriented at every step from pre to post-operative with the utilization of state-of-the-art medical technology and FDA-approved equipment, integrated with advanced surgical techniques of ophthalmologists, aiding precision, speed, and safety, maximizing the effectiveness of the treatment outcome, while providing post-treatment follow-up to ensure patients have better vision, better eye alignment, free of complications, wound heals quickly, have healthy eyes and good quality of life.