Background To investigate the optimal surgical dose for treating infantile exotropia.

Methods In this retrospective study, clinical records of 44 children who had undergone bilateral lateral rectus recessions before 4 years of age for an exotropia present before 12 months of age were studied. Children had 1 year of follow-up after surgery. Patients were separated into those who had traditional surgery and those who received a reduced recession of their lateral recti.

Results The traditional surgery group comprised 36% of the patients and the reduced recession group, 1–2 mm reduction in the recession, comprised 64% of the study group. There was borderline significance (p=0.074) when the postoperative angle of deviation was compared in the early postoperative period. The traditional group had a mean deviation of 5.25 prism dioptres (PD) of esodeviation compared with the reduced recession group having a 2.91 esodeviation. There was no statistical difference at the 1-year evaluation of the alignment. The traditional group had a mean exodeviation of 2.63 PD compared with the reduced recession group having a 2.91 PD exodeviation.

Conclusions Postoperative surgical outcome was not affected by a reduction in the amount of recession by 1–2 mm from traditional tables used for treatment of exotropia. Reducing the recession of the lateral recti reduces the risk of overcorrection in this sensory labile population.