Session: Poster session B

Comparison of the surgical treatment of superior oblique palsy: Inferior oblique myectomy versus combined inferior rectus recession

Purpose: To compare inferior oblique (IO) myectomy and IO myectomy plus combined contralateral inferior rectus (IR) recession for the treatment of superior oblique (SO) palsy

Methods: A retrospective review of medical records of patients with SO palsy who underwent surgical treatment. Group 1 (n=21) underwent IO myectomy to correct hypertropia, while group 2 (n=22) uncerwent IO myectomy plus contralateral IR recession. Comparisons were made of preoperative and postoperative vertical deviation angles in primary position and contralateral gaze, the amount of corrected hypertropia and success rate (equal or less than 4 PD).

Results: Preoperatively, there was no statistically meaningful difference in mean deviation in primary position between the two groups (11.0 PD and 13.7 PD, respectively, p>0.05), however, there was significant difference in mean vertical deviation in contralateral gaze (13.7 PD and 17.9 PD, p<0.000). Mean vertical deviations at postoperative 3 months measurements were 1.3 PD and -1.5 PD (p=0.02) in primary position and 2.0 PD and 1.2 PD in contralateral gaze (p=0.034). Mean amount of corrected hypertropia in primary position was 9,3 PD and 15.2 PD in group 1 and 2 (p=0.006), and those of contralateral gaze was 11.8 PD and 16.7 PD in group 1 and 2 (p<0.000). Success rate of group 1 was 90.5% and that of group 2 was 72.7% (p=0.058).

Conclusions: Both IO myectomy and IO myectomy combined IR recession were effective in the treatment of SO palsy. Our findings support myectomy alone as slightly more effective than combined IR recession. However, IO myectomy combined IR recession seems to be effective when vertical deviation in contralateral gaze is significantly larger than vertical deviation in primary gaze.