Clinical Findings and Surgical Results of True and Masquerading Congenital Superior Oblique Palsy.

Abstract

Purpose: To compare the clinical findings and the surgical results between true and masquerading congenital superior oblique (SO) palsy. Methods: Magnetic resonance imaging (MRI) was performed on 53 patients who were clinically diagnosed as having congenital SO palsy. The percent volume of the paretic SO muscle to the normal side was calculated and when it was equal or less than 60 %, they were defined as true SO palsy and when it was more than 60 %, they were defined as masquerading SO palsy. Clinical findings and surgical results were statistically analyzed between the two groups. Results: The true SO palsy group showed larger vertical deviation, more outward deviation, and more muscles were operated compared to the masquerading SO palsy. There was no difference in the incidence of amblyopia and the postoperative stereoacuity. Conclusions: Regardless preoperative ocular alignment, sensory outcome was similar in these two groups.