Long-term comparison of horizontal rectus surgery with vertical tendon transposition and combined vertical tendon...

To compare the efficacy of bilateral lateral rectus recession with vertical tendon transposition (LRVT) and LRVT combined with inferior oblique (IO) disinsertion for V-pattern exotropia.

The medical records of patients who had mild-to-moderate (+1 and +2) inferior oblique overaction (IOOA) and underwent half-tendon-width upward LRVT (transposition group), and LRVT with IO disinsertion (combined surgery group) for V-pattern exotropia and who had at least 3 years of postoperative follow-up were reviewed retrospectively.

A total of 45 patients were included: 22 in the transposition group and 23 in the combined surgery group. Preoperatively, there were no differences in V pattern, IOOA, or horizontal misalignment in primary position, upgaze, or downgaze between groups. The amount of exotropia in the primary position was 30.2^Δ ± 10.7^Δ in the transposition group, and 31.6^Δ ± 14.1^Δ in the combined surgery group (P = 0.974). A significant decrease in V pattern was observed in the combined surgery group and the transposition group at 6 months and 3 years postoperatively (P < 0.001). The reduction of V pattern in the combined surgery group at 6 months (20.2^Δ ± 7.8^Δ vs 15.6^Δ ± 6.9^Δ [P = 0.02]) and 3 years (20.1^Δ ± 8.1^Δ vs 15.2^Δ ± 7.1^Δ [P = 0.014]) was found to be greater than the transposition group. There were no differences in the success rate in the primary position at 6 months (P > 0.05).

Both tendon transposition with horizontal rectus surgery and combined tendon transposition and IO-weakening surgery decreased V-pattern exotropia. However, combined surgery had a greater effect on decreasing V pattern in patients with mild-to-moderate IOOA.