Long-term follow-up of surgical treatment of thyroid-associated orbitopathy restrictive strabismus.

Objective: Thyroid-associated orbitopathy (TAO) is the most frequent cause of extraocular muscle enlargement, with consecutive restrictive strabismus. The main muscles involved are inferior and medial rectus, resulting in horizontal esotropia and/or vertical strabismus. Surgery may either establish or improve binocular single vision. The aim of the present study is to describe long-term follow-up of patients who underwent horizontal or vertical TAO strabismus surgery. Methods: This observational retrospective study included 29 patients suffering from either vertical or horizontal TAO strabismus and diplopia, of whom 11 underwent bilateral medial recti muscle recession (Group A) and 18 underwent unilateral inferior rectus muscle recession (Group B). The endpoint of the study was the assessment of changes in deviation angle and diplopia across four time points (baseline, 7 days, 6 months, and 24 months) in each group. Results: In Group A, the horizontal deviation angle significantly decreased 7 days after intervention (p < 0.001), without modifications overtime. In Group B, both deviation angles in primary and down-gaze position significantly decreased from baseline, both 7 days after surgery (p < 0.001) and at 6 months (p = 0.040). An overcorrection, with an inversion of vertical deviation angle, was observed across the different time points. Conclusions: Horizontal TAO strabismus correction leads to significant improvements of deviation angle and diplopia, with a stable undercorrection overtime. Inferior rectus recession leads to more unstable results, with a trend towards overcorrection limited to the first 6 months after surgery.

Mydriasis induced by sub-Tenon's ropivacaine injection in patients undergoing strabismus surgery.

PURPOSE: To investigate the effects of sub-Tenon's capsule ropivacaine injection on pupillary diameter in strabismus surgery. METHODS: A total of 16 patients were randomly assigned to 2 groups. The ropivacaine group (R) received sub-Tenon's ropivacaine 1% (2.5-3 mL) injections. In the control group (C), general anesthesia was induced and a saline solution (2.5-3 mL) was injected in the sub-Tenon's capsule. Pupillary diameter was measured at baseline and 2 and 5 minutes from the injections. The effects of the injections were expressed as a ratio of final (5 minutes) versus basal diameter. RESULTS: A significant mydriasis occurred in the ropivacaine group when compared with the control group (Group R vs Group C ratio = 2.32, p < 0.0001) or with unoperated fellow eye (R vs unoperated eye ratio = 2.29, p < 0.0001). CONCLUSIONS: Ropivacaine in the sub-Tenon's capsule induces a mydriasis probably related to a pharmacological ciliary ganglion block.