Vertical rectus muscle recession versus combined vertical and horizontal rectus muscle recession in patients with thyroid eye disease and hypotropia

Abstract

To compare the postoperative vertical drift in patients with thyroid eye disease (TED) with hypotropia who underwent vertical rectus recession alone versus vertical rectus recession combined with horizontal rectus recession. The medical records of patients with TED who underwent strabismus surgery for hypotropia between 2006 and 2015 were reviewed retrospectively. Patients were divided into two groups: group 1 underwent vertical rectus recession only; group 2 underwent vertical rectus recession plus horizontal rectus recession. Data collection included pre- and postoperative deviation measurements and amount of surgical recession performed. The amount of postoperative vertical drift between groups was compared. Of 67 patients who underwent surgery during the study period, 18 met inclusion criteria, 9 in each group. Mean postoperative hypotropia was 24.2Δ in group 1 and 24.5Δ in group 2 (P=0.82). Mean vertical deviations were 0.3Δ and -2.2Δ (P=0.134) on postoperative day 1; -0.9Δ and -8.0Δ (P=0.043) at final follow-up for groups 1 and 2. Mean postoperative vertical drift toward hypertropia was 1.2Δ in group 1 and 6.8Δ in group 2 (P=0.048). The surgical success rate for group 1 was superior to that for group 2 (89% vs 67% [P=0.024]). There was a significantly larger postoperative vertical drift in TED patients with hypotropia who had combined vertical rectus and horizontal rectus recessions compared with those who underwent vertical rectus recession alone.