Inferior oblique muscle belly transposition and myopexy for diplopia

To evaluate the outcomes of and review the indications for Inferior oblique muscle belly transposition in adults with diplopia and small-angle hypertropia associated with mild or moderate upshoot in adduction. We retrospectively analyzed data for the six patients who underwent the technique. Surgery was performed by suturing the inferior oblique belly to the sclera at 5 mm posterior to the temporal pole of the inferior rectus. Data were collected from October 2018 to April 2020. All six patients had diplopia and mild hypertropia (≤6 prism diopters [pd]) in primary position. Mean preoperative hypertropia was 4.17 pd (range, 2-6 pd). Mean age was 51 ± 28.71 years. The diagnoses were fourth nerve paresis (5) and dissociated vertical deviation (1). All patients had mild/moderate upshoot in adduction. Torticollis was observed in four cases. Diplopia resolved in 5 of the 6 cases. The mean final vertical deviation was 2 pd in straight gaze. Torticollis was eliminated in 2 patients and improved in another 2. The upshoot in adduction was totally eliminated in the six patients. Transitory mild limitation of elevation in adduction was observed in two patients during the first week after surgery. No ocular torsion was diagnosed after surgery. Mean time from surgery was 11.5 months. No overcorrections were recorded. Inferior oblique muscle belly transposition with myopexy is a good alternative procedure in patients with diplopia associated with mild-to-moderate upshoot in adduction and small-angle hypertropia.