Longitudinal course of consecutive esotropia in children following surgery for basic-type intermittent exotropia

Purpose: To evaluate the longitudinal course of consecutive esotropia following surgery for basic-type intermittent exotropia.

Methods: Patients who underwent surgery (bilateral lateral rectus muscle recession [BLR] or unilateral lateral rectus muscle recession-medial rectus muscle resection [RR]) for the treatment of intermittent exotropia between 2011 and 2017 with a minimum follow-up period of 2 years were retrospectively reviewed. When esodeviation occurred later in patients with orthotropia or exodeviation at postoperative month 1, it was defined as delayed-onset consecutive esotropia. The number of patients with esodeviation at every follow-up and characteristics of patients were evaluated.

Results: A total of 336 patients (6.2 ± 2.1 years; 236 in the BLR group and 100 in the RR group) were included. After surgery, postoperative esodeviation decreased mostly during the 1st postoperative month in both groups. At postoperative year 2, there were 28 patients (8.3%) with consecutive esotropia: six in the RR group and 22 in the BLR group. Among the 284 patients with orthotropia or exodeviation at postoperative month 1, there were 13 patients with delayed-onset consecutive esotropia; they presented larger preoperative angle of exodeviation, poorer stereopsis, younger at the time of surgery and associated with the types of surgeries for exotropia.

Conclusions: In patients with consecutive esotropia, the angle of esodeviation decreased and patching/prismatic correction helped achieve the good surgical outcomes. However, delayed-onset consecutive esotropia and persistent esotropia also presented, requiring the reoperation. Therefore, postoperative alignment should be carefully monitored after surgery for intermittent exotropia.