A Randomized Trial of Botulinum Toxin A vs Strabismus Surgery for Esotropia >10 to ≤30PD

1. A constant or intermittent ET needing intervention with BTX-A or surgery in the judgement of the investigator meeting one of the criteria below: Infantile Esotropia (IET) * Onset prior to six months of age by parental history. * Angle measuring \>10 to ≤ 30 PD by PACT in the primary position at distance fixation on an accommodative target. Acquired Non-accommodative Esotropia (ANAET) * Onset after six months of age by parental history * Angle decreases less than 10 PD by PACT in the primary position at distance fixation with hyperopic correction. * Residual angle measuring \>10 to ≤ 30 PD by SPCT in the primary position at distance fixation on an accommodative target. Acquired Partially Accommodative Esotropia (APAET) * Onset after six months of age by parental history * Angle decreases 10 PD or more by PACT in the primary position at distance fixation with correction. * Residual angle measuring \>10 to ≤ 30 PD by SPCT in the primary position at distance fixation on an accommodative target. 2. Age at enrollment: * For IET: \> 4 months to \<17 years old * For ANAET or APAET: \>6 months to \<17 years old 3. No myopia ≥ 6.00D SE 4. Current Spectacle Correction at Time of Enrollment * For IET: No spectacle wear prior to enrollment. * For ANAET or APAET: Must be wearing spectacles if significant refractive error as defined below based upon a cycloplegic refraction within 6 months of enrollment. If no significant refractive error…