From the Guidelines
Exotropia surgery can provide significant functional benefits even after 2 years of having the condition, with improvements in binocular vision, depth perception, and peripheral vision, as well as reduced eye strain and enhanced social interactions 1. The functional benefits of exotropia surgery include:
- Improved binocular vision and depth perception
- Reduced eye strain and fatigue
- Enhanced social interactions due to improved eye contact
- Better hand-eye coordination
- Improved reading ability These benefits are supported by recent studies, including a 2023 study published in Ophthalmology, which found that surgery can promote binocular vision and normal visual function in each eye, as well as relieve asthenopia and eye fatigue 1.
Key Considerations
- The success rate for exotropia surgery ranges from 60-80%, with better outcomes generally seen in patients with good preoperative binocular potential 1.
- Even in longstanding exotropia cases (beyond 2 years), surgery can restore functional binocular vision by realigning the visual axes, allowing the brain to fuse the images from both eyes 1.
- However, the degree of functional recovery may be somewhat limited compared to earlier intervention, as prolonged misalignment can lead to sensory adaptations like suppression.
- Postoperative vision therapy is often recommended to maximize functional outcomes, particularly in cases with longstanding exotropia 1.
Surgical Approach
- Surgery typically consists of bilateral-lateral rectus-muscle recessions or unilateral-lateral rectus-muscle recession and medial rectus-muscle strengthening 1.
- The choice of surgical approach depends on various factors, including the severity of the exotropia, the presence of other ocular conditions, and the patient's overall health.
From the Research
Functional Benefits of Exotropia Surgery
The functional benefits of exotropia surgery after 2 years can be understood through the following points:
- Improved binocularity: Studies have shown that successful surgical correction of childhood large angle exotropia in adults can improve binocularity and health-related quality of life (HRQOL) 2.
- Better stereopsis: Patients who underwent surgical correction of large angle exotropia demonstrated better stereopsis after surgery, with some patients gaining normal stereopsis 2.
- Enhanced quality of life: Surgical correction of exotropia can lead to significant improvements in HRQOL, with patients experiencing better functional aspects of HRQOL, particularly in those with intermittent exotropia 2.
- Stable orthotropia: Some studies have reported stable orthotropia or minimal exotropia after surgical correction, indicating a favorable functional outcome 3, 4.
Factors Influencing Surgical Outcomes
Several factors can influence the surgical outcomes of exotropia surgery, including:
- Preoperative angle of deviation: A positive correlation has been found between the preoperative angle of deviation and dose response to surgery 5.
- Average corrected visual acuity: A negative correlation has been observed between average corrected visual acuity and response to surgery 5.
- Preoperative stereopsis: Poor or no preoperative stereopsis has been associated with better response to surgery 5.
- Type of exotropia: Intermittent exotropia may have better functional outcomes after surgery compared to constant exotropia 2.