Postoperative outcomes of patients initially overcorrected for intermittent exotropia

Esotropic overcorrection on postoperative day 1 after surgery for intermittent exotropia is generally thought to increase the likelihood of long-term satisfactory alignment; however, it is unclear why some patients who are initially overcorrected demonstrate recurrent intermittent exotropia whereas others maintain esotropic to orthotropic alignment.

The records of all patients who underwent primary surgical correction of intermittent exotropia were reviewed; those with any degree of esotropia on postoperative day 1 were included. The status at the last visit was categorized as orthotropic to <8(Δ) exotropia or having recurrent exotropia >8(Δ), monofixational esotropia <10(Δ), or esotropia >10(Δ).

A total of 63 patients met the inclusion criteria. The mean postoperative day 1 alignment was 6(Δ) ± 3(Δ) esotropia at distance and 5(Δ) ± 3(Δ) esotropia at near. At the last visit, 31 (49%) were orthotropic to <8(Δ) exotropia, 26 (41%) had recurrence of exotropia >8(Δ), and 6 (10%) had monofixational esotropia <10(Δ). There was no significant difference between outcome groups in onset age, age at surgery, stereopsis, deviation (preoperatively or on postoperative day 1), or follow-up length. Risk factor analysis revealed no association between exotropia type, surgical approach, or postoperative day 1 alignment and risk of recurrent intermittent exotropia or monofixational esotropia, although there was a trend toward recurrent intermittent exotropia in those least overcorrected.

Recommended overcorrection on postoperative day 1 for intermittent exotropia can result in esotropia, intermittent exotropia, or orthotropia. The results of overcorrection for exotropia are variable and unpredictable. We were unable to determine associations with the recurrence of exotropia or secondary esotropia.