Evaluation of the Blinq Vision Screener in the Detection of Amblyopia and Strabismus in Children

Purpose: Amblyopia is a major health problem with an estimated 2% to 4% of the population affected. Screening combined with corrective measures, such as correction of refractive error and occlusion of the dominant eye, could reduce this prevalence. A new pediatric vision scanner, the blinq (Rebion, Boston, MA), studies the foveolar quality of fixation of each eye during binocular viewing. Based on the initial premise that poor quality foveolar or non-foveolar fixation is indicative of strabismus and, potentially of amblyopia, this study evaluates the effectiveness of the blinq screening device in detecting these two conditions compared to a standard ophthalmic examination (Gold Standard) based on the recommendations of the American Association for Pediatric Ophthalmology and Strabismus. Material and Methods: A prospective study was performed on a total of 101 children between 2 and 8 years of age. These children were offered a test by the blinq screening device before a standard ophthalmological examination in the ophthalmology department of the Erasmus Hospital in Brussels, Belgium. The two tests were then compared. Results: In a pediatric population heightened with amblyopia and strabismus (prevalence of 33.4%) and based on the Gold Standard Examination, the blinq device showed a specificity of 73.1% (95% confidence interval [CI] = 60.9%-83.2%) with a sensitivity of 91.2% (95% CI = 76.3%-98.1) to detect these conditions. The positive and negative predictive values were 63.3% (95% CI = 53.4%-72.2%) and 94.2% (95% CI = 84.6%-98%) respectively. The positive likelihood ratio (LR+) was 3.39 (95% CI = 2.26-5.11) for a negative likelihood ratio of 0.12 (95% CI = 0.04-0.36). Conclusions: The blinq device has good sensitivity, but insufficient specificity to be used alone in the first line of screening. Whereas other devices on the market detect risk factors that may lead to amblyopia, the blinq pediatric vision scanner detects poor foveolar fixation and strabismus, giving it a potential advantage in sensitivity to directly detect strabismus, including microstrabismus. The blinq does not detect refractive abnormalities, however, and will therefore need to be improved in the future to be used alone in pediatric vision screening. Translational Relevance: The blinq device detects visual axis alignment abnormalities with potential impact in the early detection of strabismus and subsequent associated amblyopia.