accommodative esotropia

Accommodative esotropia is the most common esodeviation in children. Two mechanisms drive the deviation, high hyperopia averaging +4.50 D and a high ratio of accommodative convergence to accommodation (AC/A ratio) that makes the esodeviation larger at near, and both can occur in the same child.¹ The esotropia is typically intermittent at first and appears at age 2 to 3 years, often when the child is tired, ill, or daydreaming.¹ In refractive accommodative esotropia the AC/A ratio is normal. The accommodation needed to clear hyperopia of +2.00 to +7.00 D drives more convergence than fusional divergence can offset.² In nonrefractive accommodative esotropia the AC/A ratio is high. Each unit of accommodation then brings a disproportionately large increase in convergence.²

Treatment starts with the full cycloplegic hyperopic correction. The lenses do the focusing for the child, so accommodation, and with it convergence, is not stimulated.^1,2 In fully accommodative esotropia the correction straightens the eyes at distance and near. In partially accommodative esotropia the correction reduces the angle without eliminating it.² In convergence excess esotropia, bifocals relieve accommodation and its convergence at near. The minimum add that keeps the eyes aligned is prescribed.² Surgery becomes an option when a deviation persists despite the full hyperopic prescription.¹