Can the preoperative fundus extorsion in infantile esotropia predict the development of postoperative inferior oblique overaction and dissociated vertical deviation?

Objective: To evaluate the relationship between fundus extorsion before surgery and the development of inferior oblique overaction (IOOA) and dissociated vertical deviation (DVD) after surgery in patients with infantile esotropia. Design: Retrospective comparative observational study. Participants: Forty patients who had not had preoperative IOOA or DVD, and had undergone surgery for infantile esotropia were included. Methods: A fundus examination was carried out under general anesthesia before surgery. There were 21 subjects with preoperative fundus extorsion (extorsion group), and 19 subjects without torsion (no torsion group). The development of IOOA and DVD after surgery was evaluated. Results: After surgery, IOOA developed in 14 patients (66.7%) and DVD in 17 patients (80%) in the extorsion group. In contrast, IOOA developed in 2 patients (10.5%) and DVD in 6 patients (31.6%) in the no torsion group (p < 0.001, p = 0.002, respectively). Conclusions: When patients with infantile esotropia had fundus extorsion assessed on general anesthesia before surgery, IOOA and DVD were more likely to develop after surgery.