To compare the clinical outcomes of myectomy, recession, and anterior transposition (AT) of the inferior oblique muscle in congenital unilateral superior oblique palsy.

A total of 40 patients who were followed for longer than three months postoperatively and, who underwent inferior oblique myectomy, recession, or AT were evaluated retrospectively.

We compared the result of inferior oblique myectomy, recession, and AT in congenital unilateral superior oblique palsy. The decreased amounts of inferior oblique overaction (IOOA) were 2.24±0.67, 2.00±0.76, 3.00±1.15 for myectomy, recession, and AT, respectively. Improvement of superior oblique underaction was 0.80±0.66, 0.86±0.83, 1.00±0.58, and the changes in hyperdeviation were 10.96PD, 8.25PD, 14.86PD for myectomy, recession, and AT, respectively. There were no significant differences among the surgical methods. The proportion of patients who showed IOOA in the contralateral eye after operation were 20.0% in myectomy, 25.0% in recession, and 57.1% in AT.

The efficacies of myectomy, recession, and AT of inferior oblique muscle in the congenital unilateral superior oblique palsies showed no significant differences among methods. The AT group tended to show a larger effect than did the other methods, along with a high development percentage of contralateral eye IOOA. Based on these results, AT of the IO shoud be selectively chosen in more severe cases.