Predictive Value of Brückner Test in Detecting Refractive Errors among Children

Abstract

Introduction: Uncorrected refractive errors form a major ocular morbidity in children. They often go unnoticed and affect child development. The prevalence of refractive error in Indian children is 10.8%. They are known to affect the overall development of children. However, if the error is high it could lead to amblyopia or strabismus. Snellen’s visual acuity along with cycloplegic refraction is an accepted method to detect refractive errors, but in children, it needs special skill, patience and understanding. The Brückner test is useful for early detection of refractive errors especially in children. Aim: To re-evaluate the results of Brückner test in the form of sensitivity, specificity and provide data about a simpler, easy, ergonomic technique for mass screening of refractive errors. Materials and Methods: This cross-sectional study was conducted at Bharati Hospital (tertiary care hospital), Pune, Maharashtra, India, among 532 children (1064 eyes) in the age group of 2-15 years visiting the Ophthalmology Outpatient Department from October 2018 to September 2020. Position and size of pupillary crescent was recorded among children with direct ophthalmoscope. Children were classified according to errors of refraction as Emmetropia (no crescent), Myopia {inferior crescent (mild (<1/3), moderate (1/3-2/3), high (>2/3)}, Hypermetropia {superior crescent (mild (<1/3), moderate (1/3-2/3), high (>2/3)}. Subsequently, cycloplegic refraction was performed using auto-refractometer. Sensitivity, specificity, positive predictive value and negative predictive value of the test for emmetropia, myopia and hypermetropia were calculated. Subjective refraction was prescribed to children diagnosed with refractive errors during the course of this study. Results: A 275 females and 257 males (mean age 8.3 years) were included in this study, out of which, the study found 354 Emmetropic eyes, 326 Myopic eyes and 384 Hypermetropic eyes. Sensitivity of Brückner for emmetropia was 86.4%, specificity was 95.2%. Whereas for myopia, sensitivity was 95.1% and specificity was 94.6%. Also for hyperopia sensitivity was 95.3% and specificity was 98.8%. The crescent size was found to be significant (p-value<0.001) in diagnosing grades of myopia and hypermetropia as divided. Conclusion: The Brückner test has good sensitivity, specificity, positive and negative predictive value. It is a useful, accurate, and simple screening test.