IntroductionWith high increase in myopia prevalence, we aimed to assess whether Plusoptix_A09 can be used in myopic children over spectacles to predict visual acuity (VA) and myopic refraction changes.MethodsMyopic children underwent a complete ophthalmological examination. Plusoptix_A09 was performed over spectacles. VA changes, refraction changes and time since previous glasses prescription, were determined. Age, current or past history of amblyopia, presence of strabismus and self-perception of VA changes were registered.ResultsIn total, 199 patients were included. Spherical power (SP) and spherical equivalent (SE) measured by Plusoptix_A09 over spectacles predicted both VA changes (p < 0.001) and refraction changes (p < 0.001). Values of SP < − 0.06D or SE < − 0.22D indicated a VA decrease (AUC > 0.9, p < 0.01) for sensitivity and specificity of 85.1%, 82.1% and 82.6%, 83.3%, respectively. Age and ophthalmological comorbidities did not influence Plusoptix_A09 measurements (p > 0.05). Plusoptix_A09 over spectacles was a stronger predictor of VA changes when compared to children's self-perception, either in 4–9-year-old patients (p < 0.001 versus p = 0.628) and in 10–18-year-old children (OR < = 0.066 versus OR = 0.190). A decrease in SP and SE of − 0.10D in Plusoptix_A09 predicted a myopia progression of − 0.04D and − 0.05D, respectively.Conclusion/RelevanceThis study unveiled new features for the Plusoptix, a worldwide available photoscreener used inamblyopia screening. When Plusoptix is performed in children with their glasses on, it can rapidly predict myopia progression.For each decrease of − 0.10D in Plusoptix, a myopia progression of -0.05D is expected. Moreover, Plusoptix is more reliablethan children's self-perception of visual acuity changes, making it a useful tool either in primary care or ophthalmologypractice