ABSTRACT
Objectives: Axial length (AL) is an important contributor to refraction, and growth curves are gaining importance in the prediction of myopia. This study aimed to profile the distribution of ocular biometry parameters and to identify correlates of spherical equivalent refraction (SE) among school children in South India. Materials and Methods: The School Children Ocular Biometry and Refractive Error study was conducted as part of a school screening program in southern India. The enrolled children underwent tests that included vison check, refraction, binocular vision assessment, and biometry measurements. Results: The study included 1382 children whose mean (standard deviation [SD]) age was 10.18 (2.88) years (range: 5-16 years). The sample was divided into 4 groups (grades 1-2, grades 3-5, grades 6-9, and grade 10) based on significant differences in right AL (p<0.001). The mean (SD) AL (range: 20.33-27.27 mm) among the four groups was 22.50 (0.64) mm, 22.88 (0.69) mm, 23.30 (0.82) mm, and 23.58 (0.87) mm, respectively. The mean SE (range: +1.86 to -6.56 D) was 0.08 (0.65 D) in class 1 and decreased with increasing grade to -0.39 (1.20 D) in grade 10. There was a significant difference in all biometry parameters between boys and girls (p<0.001). Age, AL, and mean corneal curvature were the main predictors of SE. Conclusion: This study provides a profile of ocular biometry parameters among school children in South India for comparison against profiles from other regions across the country. The study data will form a reference for future studies assessing myopia in this ethnicity.
Subject(s)
Myopia , Refractive Errors , Male , Female , Humans , Child , Child, Preschool , Adolescent , Refractive Errors/diagnosis , Refractive Errors/epidemiology , Refraction, Ocular , Myopia/diagnosis , Biometry/methods , India/epidemiologyABSTRACT
PURPOSE: To compare the axial length measurements obtained by a new swept source optical coherence tomography based biometer-ARGOS with partial coherence interferometry based biometer -IOL master in school children between the ages of 11-17. METHODS: A prospective, cross-sectional, device comparison study was conducted in a school vision screening program comparing the axial length (AL) and corneal curvature (K) measurements obtained by two biometers- ARGOS and IOL master. Children with 6/9 vision or better, without any ocular abnormalities were included in the study. Two trained optometrists performed the measurements and were masked for the outcome measures. RESULTS: The sample size was 188 with a mean(SD) age of 13.88±1.69 years, of which 101 were boys. The mean (SD) AL was 23.94± 1.01 mm with Argos and 23.83 ± 1.03 mm with IOL Master (paired t-test, p>0.05). The mean K was 43.62D±1.59 with Argos and 43.64D±1.61 with IOL master (paired t-test, p>0.05). There was a strong positive correlation between the biometers for AL (r = 1.00, p<0.0001) and K (r = 0.99, p<0.0001). The mean difference in axial length between the two biometers was 0.11± 0.04 mm and the limits of agreement were between -0.02 to -0.19. The mean difference in corneal curvature was 0.02±0.15D and the limits of agreement were between -0.28 to 0.32D. CONCLUSION: Axial length measurements using SS-OCT and PCI based biometers were in agreement and comparable among children between the ages of 11 to 17.
