Purpose: To analyse objective ocular torsion among patients with infantile esotropia and to determine the effects of unilateral horizontal rectus surgery.
Methods: Sixty-eight patients (136 eyes) (range 4 to 16 years) who underwent unilateral horizontal rectus surgery for infantile esotropia participated in this retrospective single-centre study. Objective ocular torsion using fundus photography was assessed before surgery and 1 year later. We defined three groups of patients based on preoperative qualitative objective ocular torsion: physiological extorsion and pathological extorsion and intorsion. For each group, the disc-foveal angle was measured and analysed both before and after surgery. We looked for possible correlations between amount of esodeviation and disc-foveal angle size.
Results: Preoperatively, 28 (41%) patients had + 6.73 (± 2.66) degrees of physiological extorsion. Thirty-one (46%) patients had + 12.94 (± 3.67) degrees of pathological extorsion. Nine (13%) patients had - 1.99 (± 2.52) degrees of intorsion. After surgery, the number of subjects with physiological extorsion increased to 45 (66%). The number of patients with pathological extorsion decreased to 17 (25%) and the mean disc-foveal angle was significantly reduced by 1.80°. Six (9%) patients presented intorsion and the mean disc-foveal angle was significantly reduced by 2.28°. For the pathological extorsion group, the size of the disc-foveal angle before surgery was positively correlated to its reduction after surgery. Disc-foveal angle variation and distance esodeviation variation after surgery were positively correlated.
Conclusions: These results highlight that pathological objective ocular torsion can be frequently found in infantile esotropia and is decreased after unilateral recession-plication surgery.
Keywords: Fundus photography; Infantile esotropia; Strabismus surgery; Torsion abnormality.