Nabie R, et al. - In this prospective study, researchers assessed the results of inferior oblique anteriorization for the treatment of large-angle hypertropia secondary to superior oblique palsy and determined predictors of success and the occurrence of antielevation syndrome. Twenty-five patients, the mean age of patients at surgery was 19.8 ± 11.9 years (range, 4-49), with unilateral congenital and acquired superior oblique palsy who had a primary position hypertropia of at least 25 ^Δ underwent inferior oblique anteriorization in the paretic eye. One-muscle surgery, including inferior oblique anteriorization, can be conducted in a unilateral superior oblique palsy to overcome a large-angle hypertropia of > 25 ^Δ. Extorsion is a risk factor, which increases the probability of failure.