Purpose : To evaluate the results of anterior and nasal transposition (ANT) of the inferior oblique muscle (IO) in patients with the IO muscle overaction

Methods : This retrospective case series included patients with IO muscles overaction, in whom ANT of the IO muscle was performed. In patient with simultaneous horizontal deviation, horizontal strabismus surgery was also performed. They were evaluated pre- and post-operatively for alignment and oculomotor examination.

Results : Seven patients with the mean age of 9.2±5.2 years were included for the study. Unilateral and bilateral ANT was performed in one and 6 patients respectively. Patients were followed for a mean of 32.5±9 months. IO muscle overaction was eliminated in all patients. Antielevation syndrome was developed in 2 patients. One patient needed further operation for residual horizontal deviation.

Conclusion : It seems that ANT is useful for the treatment of patients with the IO overaction. However, the risk of antielevation syndrome should be considered.