What are the treatment options for a child with monocular esotropia?

Treatment of Monocular Esotropia in Children

All children with monocular esotropia should undergo immediate cycloplegic refraction to detect hyperopia, followed by full optical correction with eyeglasses (prescribed for ≥+1.00 D), and concurrent amblyopia treatment before considering surgical intervention. 1, 2

Initial Diagnostic Workup

The comprehensive evaluation must include:

• Cycloplegic refraction to identify any hyperopia, as adequate cycloplegia is essential due to increased accommodative tone in children 1
• Prism and alternate cover test to quantify the total deviation angle at both distance and near fixation 1
• Assessment for amblyopia through visual acuity testing and fixation pattern evaluation, as children with esotropia are at high risk 1, 2
• Funduscopic examination to rule out retinal or optic nerve abnormalities that could cause sensory strabismus 1
• Evaluation of ductions and versions to distinguish infantile/accommodative esotropia from paretic or restrictive causes 1

Treatment Algorithm

Step 1: Optical Correction (First-Line)

Prescribe full cycloplegic hyperopic correction for any hyperopia ≥+1.00 D immediately. 1, 2 The threshold for prescribing hyperopic eyeglasses is lower in children with esotropia compared to those without strabismus. 1 For accommodative esotropia, eyeglasses alone may restore alignment in most cases. 2

Step 2: Amblyopia Management (Before Surgery)

Amblyopia treatment must be initiated and completed before surgical planning, as it may alter the angle of strabismus and increase the likelihood of postoperative binocularity. 1 Treatment typically involves patching or other occlusion therapy. 1

Critical pitfall: Patching in children with monofixation syndrome may cause breakdown of fusional control, resulting in decompensation to a large esotropia. 3 Monitor closely during amblyopia treatment.

Step 3: Surgical Intervention

Surgery is indicated when:

• The esotropia persists despite full optical correction 1
• Amblyopia treatment has been completed 1
• Binocular alignment needs to be established to maximize binocular potential 1

Surgical approach based on deviation pattern:

• Bilateral medial rectus recession: Recommended when distance deviation exceeds near deviation, with higher success rates (64.5% for 3-4 muscle surgery) and lower reoperation rates compared to unilateral surgery 2, 1
• Unilateral recession-resection: Consider when near deviation is greater than distance deviation 2

Timing considerations: Early surgical correction (before age 2 years) improves sensory outcomes for infantile esotropia by minimizing the duration of constant misalignment, though motor outcomes are not improved by earlier surgery. 1 However, untreated patients with free alternation and no anisometropia may retain good visual acuity if surgery is delayed, particularly when ongoing therapy access is limited. 4, 5

Post-Surgical Management

• Monitor for consecutive esotropia, which may cause diplopia but is often temporary; consider temporary membrane prisms with gradually reduced power if it persists 2
• Pain management with non-narcotic analgesics and combination antibiotic-corticosteroid preparations for the first week 2
• Counsel parents about risks including orbital cellulitis, slipped or lost muscle, recurrence of esotropia (37.3% success rate for 2-muscle surgery), or consecutive exotropia 2

Long-Term Follow-Up

• Every 6-12 months for well-aligned children without amblyopia 2, 6
• More frequently if visual acuity decreases or esotropia increases 2, 6
• Annual hyperopia assessment at minimum, as refractive error can change 2
• Lifelong monitoring is essential as patients remain at high risk for developing amblyopia, losing binocular vision, or experiencing recurrence 2

Additional Treatment Modalities

Other options include:

• Bifocal eyeglasses for accommodative esotropia with high AC/A ratio 1
• Prism therapy in select cases 1
• Botulinum toxin injection as an alternative to surgery (moderate evidence, discretionary) 1

Key Clinical Pearls

Anisometropia is a critical risk factor: The presence of anisometropia significantly increases amblyopia risk in monocular esotropia (62.5% of amblyopic patients had anisometropia). 4 Correct any anisometropia promptly.

Binocular alignment should be established as soon as possible to maximize binocular potential, prevent or facilitate amblyopia treatment, and restore normal appearance. 1 The goal is to optimize both visual acuity and binocular alignment to maximize quality of life. 1