The effect of anterior transposition of the inferior oblique muscle on eyelid configuration and function

Purpose: To evaluate the alteration of lower lid configuration and function with anterior transposition surgery of the inferior oblique (IO) muscle. Patients and Methods: A prospective clinical trial was conducted on a consecutive series of patients underwent anterior transposition of the IO as a sole operation. All patients received a thorough ophthalmic examination 1 day before and 3 months after surgery. Output parameters were consisted of palpebral fissure, margin reflex distance 1u2, lower lid function, hertel value, and lower lid crease. The differences of the collected data were calculated for statistical significance by using the Wilcoxon test. Results: A total of 19 eyes of 16 consecutive patients were included. The median preoperative grade of IO overaction was 3.5 (ranging from 3 to 4), which decreased to 0 (ranging from 0 to 2) postoperatively (P 0.05). No significant change was observed in all parameters 3 months postoperatively (P 0.05). Conclusion: In this study, no significant effect on lower lid configuration and function was observed following IO anterior transposition in which the disinserted muscle was placed posterior to inferior rectus insertion.