Accuracy of noncycloplegic photorefraction using Spot photoscreener in detecting amblyopia risk factors in preschool children in an Indian eye clinic

Abstract

Purpose: To evaluate the accuracy of Spot photoscreener (PS) as a noncycloplegic photorefractor in detecting amblyopia risk factors (ARFs) in preschool children in an Indian eye clinic setting. Also, to derive appropriate cutoff values for screening to obtain maximum sensitivity and specificity of the device in detecting ARF. Methods: This was a cross-sectional study conducted in the outpatient pediatric eye clinic at a tertiary eye care institute. A Spot PS was used to screen all the children between the ages of 6 months and 5 years that presented to the eye clinic from August 2018 to October 2018. This screening was followed by a complete eye examination, including cycloplegic refraction by a masked examiner. The 2013 American Association for Pediatric Ophthalmology and Strabismus (AAPOS) guidelines were considered the standard cutoff values for clinically significant refractive error in children younger than 5 years of age. Results: The study comprised of 219 children. The Spot PS diagnosed 135 (61.64%) children with ARF as compared with 124 (56.62%) children detected by clinic examination. For ARF detection, the Spot photoscreeneer had 85.48% sensitivity, 69.47% specificity, 78.52% positive predictive value and 78.57% negative predictive value. The sensitivity for detection of strabismus and hypermetropia was very low (42% and 36%, respectively). The 95% limits of agreement ranged from −5.48 to +5.59 diopters (D) with a bias of 0.06 D for spherical equivalent between noncycloplegic photorefraction and cycloplegic refraction. Conclusion: The Spot PS may be used as a screening tool to detect ARF in children younger than 5 years of age keeping its limitations in consideration. However, the performance can be improved by modifying the cutoff values for the referral.

Keywords

• amblyopia
• cyclorefraction
• photoscreener