Abstract Body:

Purpose: Controversy exists about the proper time of surgery for infantile exotropia (XT). The aim of this study was to review the degree of postoperative ocular alignment, sensory outcomes, and need for re-operation after surgical managements of infantile XT.

Study Design: Observational retrospective case series

Methods: We reviewed clinical records of 49 patients with constant infantile XT> 25 Δ, who underwent strabismus surgery in a tertiary referral university center between 2004 and 2014. The study was approved by the local Ethics Committee and was compliant with the principles of the Declaration of Helsinki revised in October 2008. Minimum follow up duration after surgery was 2 years. Post-operative binocular sensory status was assessed using Worth 4-dot and Titmus stereoacuity tests. Corrective surgery was offered to patients with more than 10 Δ XT or 5 Δ esotropia (ET) after first operation.

Results: Performing surgery at a younger age led to more need for corrective surgery (P= 0.005). Patients who developed consecutive ET had lower age at the time of initial surgery (P= 0.039). Among 20 patients who were testable for sensory outcome assessment, only 4 patients developed stereopsis while 15 patients achieved bifixation in Worth 4-dot test. All of the 4 patients who had post-operative measurable stereoacuity had initial surgery after the age of one.

Conclusions: Our results suggest that earlier surgery does not necessarily lead to better sensory outcomes and it may also result in more need for corrective surgery.