Treatment Options for Strabismus
The primary treatment options for strabismus include optical correction with glasses or prisms, orthoptic exercises, botulinum toxin injections, and surgical correction, with the specific approach determined by the type and severity of strabismus. 1
Non-Surgical Treatment Options
1. Optical Correction
- Glasses or Prisms: Often first-line treatment
- Fresnel or ground-in prisms can provide temporary or long-term relief
- Success rate of 70-80% for appropriate candidates 1
- Particularly useful for accommodative esotropia and small-angle deviations
2. Orthoptic Exercises
- Office-based exercises may be more effective than home-based exercises
- Success rate of 50-60% in adults (lower than in children) 1
- Most beneficial for convergence insufficiency and certain forms of intermittent exotropia
3. Botulinum Toxin Injections
- Can be used alone or in combination with surgery 2
- Temporary effect that may provide long-term improvement in select cases
- Particularly useful for:
- Small-angle deviations
- Acute-onset strabismus
- Patients who are poor surgical candidates
Surgical Treatment
Indications for Surgery
Surgery is indicated for:
- Ocular misalignment causing cosmetic concerns
- Persistent diplopia
- Abnormal head posture
- Significant asthenopia (eye strain)
- Reduced binocular vision 1
Surgical Techniques
- Recession: Weakening procedure by moving muscle insertion further back
- Resection: Strengthening procedure by shortening muscle
- Adjustable Sutures: Allows post-operative fine-tuning of alignment
- Various techniques exist (bowtie, noose, semiadjustable)
- Timing of adjustment varies from immediately post-op to several days later
- Particularly helpful in reoperations and unpredictable cases 2
- Tenotomy: Partial or central snip procedure for small deviations (<8 prism diopters horizontally, <3 prism diopters vertically) 2
- Myopexy: Muscle fixation technique
Outcomes and Success Rates
- Approximately 80% of patients achieve satisfactory alignment with one procedure
- Up to 95% success with a second procedure
- Over 95% resolution of diplopia in primary position for those with pre-existing diplopia 1
Special Considerations
Adult Strabismus Surgery
Adult strabismus surgery presents unique challenges:
- Anticoagulation: Many surgeons do not routinely stop anticoagulants, though consultation with the prescribing physician is advised 2
- Small Deviations: Even microtropias (<8 prism diopters) can cause significant symptoms and may require intervention 2
- Adjustable Sutures: Often preferred in adults to minimize risk of post-operative diplopia 2
Complications
Potential complications range from mild to serious:
- Common: Visible muscle insertion, visible/dark sclera, persistent injection, overcorrection or undercorrection
- Rare but serious: Endophthalmitis (1 in 30,000-185,000), slipped muscle (1 in 1,500), lost muscle (1 in 4,500), retinal detachment (1 in 10,000-40,000) 2
Treatment Algorithm
Initial Assessment:
- Determine type and severity of strabismus
- Assess vision and treat any correctable vision loss
- Evaluate for binocular potential
First-line Treatment:
- For accommodative strabismus: Optical correction
- For small-angle deviations: Prism correction or orthoptic exercises
- For convergence insufficiency: Orthoptic exercises
Second-line Treatment:
- For persistent strabismus after non-surgical management: Consider botulinum toxin or surgery
- For large-angle deviations: Surgical correction is often necessary
Post-treatment Monitoring:
- Regular follow-up to assess alignment, binocular function, and symptoms
- Adjust treatment as needed based on response
Important Considerations
- Early intervention is critical, especially in children, to prevent amblyopia and promote development of binocular vision 3
- The goal of treatment has evolved from simple ocular alignment to restoration of stereopsis 4
- Treatment should be individualized based on the specific type of strabismus, patient age, and presence of associated conditions