Elongation of the inferior rectus tendon with fascia lata graft for large vertical squint angles in patients with Graves’ orbitopathy

Purpose To investigate the use of fascia lata (FL) grafts for inferior rectus muscle (IRM) tendon elongation in patients with large vertical squint angles with Graves’ orbitopathy (GO). Methods In this retrospective study, we included a consecutive series of 20 eyes of 13 patients with GO who underwent IRM tendon elongation with FL. Orthoptic and ophthalmologic examinations including measurement of the head posture, the extent of deviation in primary position (PP), elevation, motility, and binocular diplopia at the tangent of Harms were conducted preoperatively and after a mean postoperative time of 10.8 (5.0–35.0) months in all patients. Results The mean total repositioning distance was 9.3 ± 3.6 (3.5–16.0) mm. Postoperatively, we found a significant increase in elevation (5.4 ± 2.4 vs. 2.7 ± 2.4 mm preoperatively, p = 0.011). A significant reduction in vertical squint angle (2.8 ± 3.7 vs. 20.2 ± 18.8 Δ preoperatively, p = 0.004), chin elevation (2.3 ± 3.7 vs. 12.9 ± 6.3° preoperatively, p