Outcomes of hang-back recession for restrictive strabismus associated with thyroid eye disease

To evaluate the outcomes of hang-back recession applied to mechanically restricted rectus muscles in patients with thyroid eye disease (TED)-related strabismus, focusing on alignment stability and surgical success.

This retrospective observational study included patients with TED who underwent hang-back recession of mechanically restricted rectus muscles for diplopia and/or restrictive ocular motility. Surgical dose was determined based on preoperative deviation magnitude and intraoperative findings rather than a fixed nomogram, and postoperative alignment outcomes were assessed at standardized follow-up visits.

Fourteen patients (17 eyes) were included. Mean age was 48.8 ± 10.2 years, and all patients presented with diplopia. Horizontal deviation (10 eyes) showed a significant reduction at all postoperative time points at both near and distance fixation (p = 0.005), while vertical deviation (8 eyes) also demonstrated significant improvement throughout follow-up (p ≤ 0.012). Improvement was evident from the first postoperative week, with stable alignment achieved by the third postoperative month. No overcorrection occurred after horizontal surgery, and a mild vertical overcorrection (4 prism diopters) was observed in one patient. Based on a success criterion of postoperative deviation within ± 5 prism diopters, surgical success was achieved in 100% of cases, and no reoperation was required.

Hang-back recession may provide effective and stable correction of TED-related strabismus. This tension-free approach was associated with favorable postoperative alignment and a low incidence of clinically significant overcorrection in the present series. These findings should be interpreted considering the relatively small cohort and the absence of a control group.