Interventions for infantile esotropia.

Background: Infantile esotropia (IE) is the inward deviation of the eye. Various aspects of the clinical management of IE are unclear; mainly, the most effective type of intervention and the age at intervention.

Objectives: To examine the effectiveness and optimal timing of surgical and non-surgical treatment options for IE to improve ocular alignment and achieve or allow the development of binocular single vision.

Search Methods: We searched CENTRAL, MEDLINE, Embase, one other database, and three trials registers (November 2021). We did not use any date or language restrictions in the electronic searches for trials.  SELECTION CRITERIA: We included randomized trials and quasi-randomized trials comparing any surgical or non-surgical intervention for IE.

Data Collection And Analysis: We used standard Cochrane methodology and graded the certainty of the body of evidence for six outcomes using the GRADE classification.

Main Results: We included two studies with 234 children with IE. The first study enrolled 110 children (mean age 26.9 ± 14.5 months) with an onset of esotropia before six months of age, and large-angle IE defined as esotropia of ≥ 40 prism diopters. It was conducted between 2015 and 2018 in a tertiary care hospital in South Africa. It compared a maximum of three botulinum toxin injections with surgical intervention of bimedial rectus muscle recession, and children were followed for six months. There were limitations in study design and implementation; the risk of bias was high, or we had some concerns for most domains.  Surgery may increase the incidence of treatment success, defined as orthophoria or residual esotropia of ≤ 10 prism diopters, compared with botulinum toxin injections, but the evidence was very uncertain (risk ratio (RR) of treatment success 1.88, 95% confidence interval (CI) 1.27 to 2.77; 1 study, 101 participants; very low-certainty evidence). The results should be read with caution because 23 children with > 60 prism diopters at baseline in the surgery arm also received botulinum toxin at the time of surgery to augment the recessions. There was no evidence of an important difference between surgery and botulinum toxin injections for over-correction (> 10 prism diopters) of deviation (RR 0.29, 95% CI 0.06 to 1.37; 1 study, 101 participants; very low-certainty evidence), or additional interventions required (RR 0.66, 95% CI 0.36 to 1.19; 1 study, 101 participants; very low-certainty evidence). No major complications of surgery were observed in the surgery arm, while children experienced various complications in the botulinum toxin arm, including partial transient ptosis in 9 (16.7%) children, transient vertical deviation in 3 (5.6%) children, and consecutive exotropia in 13 (24.1%) children. No other outcome data for our prespecified outcomes were reported.  The second study enrolled 124 children with onset of esotropia before one year of age in 12 university hospitals in Germany and the Netherlands. It compared bilateral recession with unilateral recession surgeries, and followed children for three months postoperatively. Very low-certainty evidence suggested that there was no evidence of an important difference between bilateral and unilateral surgeries in the presence of binocular vision (numbers with event unclear, P = 0.35), and over-correction (RR of having exotropia 1.09, 95% CI 0.45 to 2.63; 1 study, 118 participants). Dissociated vertical deviation, latent nystagmus, or both were observed in 8% to 21% of participants.

Authors' Conclusions: Medial rectus recessions may increase the incidence of treatment success compared with botulinum toxin injections alone, but the evidence was very uncertain. No evidence of important difference was found between bilateral surgery and unilateral surgery.  Due to insufficient evidence, it was not possible to resolve the controversies regarding type of surgery, non-surgical intervention, or age of intervention in this review. There is clearly a need to conduct good quality trials in these areas to improve the evidence base for the management of IE.