Validation of the PlusOptix S12C for detecting amblyopia risk factors in a tertiary care young paediatric population

To evaluate the sensitivity and specificity of the PlusOptix S12C device in detecting amblyopia risk factors (ARFs) in children aged 2-7 years, in accordance with the 2020 Israeli Ministry of Health (MOH) directives and the 2021 American Association for Pediatric Ophthalmology and Strabismus (AAPOS) guidelines.

A cross-sectional, observational study was conducted at a tertiary care hospital. Children presenting for vision testing were screened using the PlusOptix S12C device, and results were compared with the gold standard cycloplegic refraction and cover test. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated for the overall population and subpopulations based on ARFs.

A total of 196 children aged 24-84 months were screened (46.4% boys, mean age: 56.94 ± 17.52 months). The PlusOptix S12C demonstrated an overall sensitivity and specificity of 85.5% and 82.3%, respectively. Sensitivity for hyperopia (>4.00 D) was lower (47.7%), while specificity was 81.7%. For strabismus (>8 Δ), sensitivity and specificity were 67.8% and 91.1%, respectively. The device failed to produce readings in 21.9% of children, primarily those with significant refractive errors or strabismus.

The PlusOptix S12C demonstrated good overall sensitivity and specificity for detecting ARFs, making it a valuable tool for large-scale paediatric vision screening, including in very young children. However, its inherent limitations in detecting high hyperopia and strabismus, combined with the high prevalence of these conditions in the untestable group, highlight the need for supplementary evaluation. Children who receive a 'no result' or 'unable-to-read' outcome on the device should be referred for a full examination, including cycloplegic refraction, to ensure ARFs are not missed. While the device aligns well with the 2021 AAPOS and MOH guidelines, careful attention to its limitations in high-risk subpopulations is essential to optimise screening efficacy and outcomes.