Outcome of Unilateral Lateral Rectus Resection in Patients with Age-Related Distance Esotropia

Purpose: We sought to evaluate the surgical outcomes of unilateral lateral rectus (LR) resection among patients with age-related distance esotropia (ARDE). Methods: We conducted a retrospective review of 39 patients who underwent unilateral LR resection for ARDE between January 2019 and November 2024 performed by a single surgeon at a tertiary eye centre in Brisbane, Queensland. The inclusion criteria included symptomatic horizontal diplopia at distance, comitant esotropia that was at least 25% greater at a distance than nearby, and absence of an abduction deficit or neurologic abnormality. In all but one procedure, an adjustable-suture technique was used. The amount of LR resection was based on a 1 mm per 4 prism dioptre (PD) personal surgical table. Pre- and postoperative measurements of deviation close up at near (33 cm) and at a distance (6 m) were obtained using prism and alternate cover testing. Results: The mean (±SD) patient age was 68.1 ± 9.7 years (range: 44–91). The mean preoperative esotropia measured 14.3 ± 2.7 PD at a distance and 4.7 ± 3.3 PD nearby. The mean LR resection was 3.8 ± 0.7 mm (range: 3.0–6.0 mm), with a mean follow-up of 18 months (range: 9–26). Diplopia was resolved in 97% (38/39) of the patients. At the final follow-up, 85% (33/39) were orthophoric at a distance, and all were orthophoric nearby. Five patients (13%) required postoperative adjustment, four of whom achieved orthophoria. Three patients had minimal residual esotropia (<5 PD). Conclusions: Unilateral LR resection with adjustable sutures provides a safe, effective, and targeted surgical option for ARDE, achieving high rates of distance orthophoria and diplopia resolution without compromising near alignment. Prospective long-term studies are warranted to confirm durability and refine surgical dosing.