What is the treatment for exophoria?

Treatment of Exophoria

Convergence orthoptic exercises are the first-line treatment for symptomatic exophoria, particularly for convergence insufficiency, which is characterized by exophoria greater at near than distance. 1

Diagnosis and Assessment

A proper diagnosis requires a comprehensive sensorimotor examination to identify:

• Exophoria or intermittent exotropia greater at near than distance
• Insufficient positive fusional vergence at near (<20 prism diopters)
• Distant near point of convergence (>6cm)
• Appropriate optical correction for near activities 1

Symptoms commonly include:

• Eyestrain and headaches
• Blurred vision
• Horizontal diplopia (especially with near work)
• Need to close one eye during reading
• Difficulty concentrating
• Visual perception of text movement
• Reduced reading comprehension 1

Treatment Algorithm

Step 1: Observation

• For mild, occasional symptoms that don't bother the patient
• For patients who decline treatment 1

Step 2: Non-surgical Management

1. Convergence Orthoptic Exercises

   • First-line treatment for symptomatic cases
   • Office-based training is more effective than home-based exercises for improving positive fusional vergence 1
   • Exercises target the proximal and fusional components of convergence 2
   • Success rates for orthoptic vision therapy in intermittent exotropia have been reported at 59% 3

2. Optical Correction

   • Ensure appropriate refractive correction
   • Consider prism reading glasses for persistent symptoms 1
   • Base-in prisms may be used, though evidence suggests they may not be more effective than regular spectacles 4

3. Overminus Lens Therapy

   • May temporarily improve control of intermittent exotropia while wearing the lenses
   • Benefits typically don't persist after treatment ends 4

Step 3: Surgical Management

Consider surgery when:

• A manifest distance deviation is present
• Symptoms are consistent despite non-surgical treatment
• Prism reading glasses are unsatisfactory 1

Surgical options include:

• Lateral rectus recession (based on distance deviation)
• Medial rectus resection (based on near deviation)
• Recession with slanting of reattached muscle insertions
• Augmentation of lateral rectus recessions 1

Effectiveness of Treatments

• Orthoptic exercises have shown significant improvement in near point of convergence (from 16.6 to 8.4 cm) and normalization in 47/55 cases 2
• Fusional reserves normalized in 29/50 cases with orthoptic exercises 2
• Asthenopic symptoms improved in 65/78 patients with orthoptic exercises 2
• For intermittent exotropia, pooled success rates from literature review: orthoptic vision therapy (59%), surgery (46%), occlusion therapy (37%), overminus lens therapy (28%), and prism therapy (28%) 3
• Case studies have shown successful long-term outcomes with vision therapy for adults with basic exotropia, eliminating symptoms without surgery 5

Important Considerations

• Results of convergence training are generally less consistent in adults than in children 1
• Risk of inducing postoperative diplopia at distance after surgery should be discussed, particularly for patients without exophoria/exotropia at distance or with poor divergence amplitudes 1
• Combined approaches using vision therapy and surgery may be beneficial in cases where either treatment alone is insufficient 6
• Regular monitoring is necessary as symptoms may vary with changes in near work demands 1

Provider Recommendations

Diagnosis and management of exophoria, particularly convergence insufficiency, requires the expertise of an ophthalmologist familiar with this condition, potentially with assistance from an orthoptist or optometrist 1.