Postoperative Changes in Alignment in Patients Surgically Corrected for Esotropia and Exotropia in a Tertiary Government Hospital

Abstract

Objective. To compare the postoperative alignment of patients surgically corrected for esotropia or exotropia 6 weeks and 6 months after surgery.
Method. This retrospective study reviewed clinical records of patients who underwent horizontal muscle surgery at the University of the Philippines-Philippine General Hospital from 2010 to 2014. The changes in alignment from 1 week to 6 weeks and from 1 week to 6 months after surgery were compared for overcorrection, undercorrection, and adequate correction groups. ANOVA and Pearson correlation were used.
Results. Twenty two esotropia and 10 exotropia patients were included. Overcorrected esotropia patients had an esotropic change in alignment (15.50+13.44 PD after 6 weeks, p=0.026; 25+18.38 PD after 6 months, p=0.008). Under corrected esotropia patients had an exotropic change in alignment (-1.25+5.91 PD after 6 weeks, p=0.026;-4.38+14.16 PD after 6 months, p=0.008). Undercorrected exotropia patients had an esotropic change in alignment (6.67+6.35 PD after 6 weeks, p=0.028; 6+9.85 PD after 6 months, p=0.024). The presence of vertical deviations in esotropia caused an exotropic change in alignment after 6 months (p=0.03).
Conclusion. Although an exotropic drift is more commonly reported, fusional vergences may account for postoperative alignment changes towards orthotropia.