Introduction To evaluate the outcomes of the superior oblique split tendon lengthening (SOSL) procedure for Brown syndrome (BS).

Methods At a single institution, all patients who underwent SOSL surgery for BS from 2013 to 2019 were reviewed retrospectively. We looked at the surgical outcomes and complications in a total of 20 eyes of 18 patients. The superior oblique (SO) muscle was isolated and then extended. The tendon was then split centrally into equal halves. Two 6–0 polyglactin sutures were then placed on each end of the split tendon 6–10 mm apart. To complete the Z-cut, the split tendon was cut distal to the preplaced sutures. The sutures were then tied to produce the split Z-tendon lengthening.

Results Eleven (55%) out of 20 eyes were female patients. The mean age was 6.6 years (range 2–17 years). The mean follow-up was 26.8 months (range 5–72 months). The mean degree of preoperative limitation of elevation on adduction was −3.6±0.58 preoperatively and −0.75±1.25 postoperatively (p=0.0001). Preoperatively, the mean degree of vertical deviation at near was 3.5±7.62 and at distance was 3.10±7.84 prism diopters (PD), respectively. Postoperatively, the mean vertical deviation was 2.77±4.75 and 2.10±4.08 PD at near and distance, respectively. Postoperative complications included haematoma in one patient (5%), overcorrection in two patients (10%) and one patient required reoperation (5%).

Conclusion SOSL is a safe procedure that surgeons can consider in managing patients with BS.