Preoperative Factors Affecting Stereopsis after Surgical Alignment of Acquired Partially Accommodative Esotropia

Despite successful ocular realignment, many strabismus patients never develop high levels of stereopsis. The purpose of this study was to determine preoperative factors that affect postoperative stereopsis in patients with acquired partially accommodative esotropia (APAET).

This was a retrospective chart review of patients who underwent successful surgery for APAET. We compared preoperative factors between patients achieving postoperative stereopsis of 100 seconds of arc or better versus those with worse than 100 seconds of arc.

Fifty-seven patients met our inclusion criteria. Twenty-four (42%) had a final stereopsis of 100 seconds of arc or better. The mean age of onset of esodeviation for patients attaining stereopsis of 100 seconds of arc or better was 31.8 ± 12.9 months, versus 23.9 ± 10.0 months (p = 0.012) for patients with worse than 100 seconds of arc. Duration of constant misalignment was not significantly different between the two groups (30.1 ± 18.5 for patients attaining 100 seconds of arc versus 27.3 ± 18.6 months; p = 0.57). A multivariate regression analysis found older age of onset to be the only predictive factor for achieving better postoperative stereopsis (odds ratio 1.065, 95% CI: 1.014-1.118).

Age of onset appears to be the most important factor affecting postoperative stereopsis in patients with APAET. Patients with an age of onset after 36 months tended to have better outcomes regardless of the duration of misalignment. Duration of misalignment and age at surgery did not have a significant impact on postoperative stereopsis in our patient population.