Superior oblique tuck-effectiveness in reducing vertical deviations when performed as a primary versus secondary procedure in superior oblique paresis.

Abstract

To quantify the effectiveness of superior oblique tuck (SOT) surgery in patients with a hyperdeviation secondary to superior oblique paresis (SOP). Surgical outcomes were compared in patients undergoing SOT surgery as a primary procedure with those who had previously undergone ipsilateral inferior oblique weakening surgery. This retrospective study assessed surgical outcomes from all patients undergoing SOT surgery for SOP between 2012 and 2021 across 2 hospitals. The effectiveness of SOT surgery in reducing the hyperdeviation was assessed in the primary position (PP) and in contralateral elevation and depression. Results were compared between those undergoing primary SOT surgery with those who had previously undergone ipsilateral inferior oblique weakening surgery. A total of 60 SOT procedures were performed between 2012 and 2021. 7 were removed due to incomplete data. The remaining 53 cases experienced a mean reduction in hyperdeviation of 6.5 prism dioptres (PD), 6.7PD and 12.0PD in the PP, contralateral elevation and contralateral depression respectively. In eyes with previous IO weakening, the reduction of hyperdeviation was larger than in those eyes with no previous IO weakening surgery, with mean reductions of 8.0PD vs 5.2PD, 7.4PD vs 6.2PD and 12.4PD vs 11.6PD in the PP, contralateral elevation and contralateral depression respectively. SOT surgery is a safe and effective procedure with high patient satisfaction and resolution of symptoms in those patients with troublesome diplopia in downgaze secondary to SOP. This is true in both unoperated eyes and in those who have previously undergone inferior oblique weakening surgery.