Retinal nerve fiber layer thickness in normal Indian pediatric population measured with optical coherence tomography

Purpose: To measure the peripapillary retinal nerve fiber layer (RNFL) thickness in normal Indian pediatric population. Subjects and Methods: 120 normal Indian children ages 5-17 years presenting to the Pediatric Clinic were included in this observational cross-sectional study. RNFL thickness was measured with stratus optical coherence tomography (OCT). Children with strabismus or amblyopia, with neurological, metabolic, vascular, or other disorders and those with abnormal optic discs were excluded. One eye of each subject was randomly selected for statistical analysis. The effect of age, refraction and gender on RNFL thickness was investigated statistically. Result: OCT measurements were obtained in 120 of 130 (92.3%) subjects. Mean age was 10.8 +/- 3.24 years (range 5-17). Average RNFL thickness was (+/- SD) 106.11 +/- 9.5 mu m (range 82.26-146.25). The RNFL was thickest inferiorly (134.10 +/- 16.16 mu m) and superiorly (133.44 +/- 15.50 mu m), thinner nasally (84.26 +/- 16.43 mu m), and thinnest temporally (70.72 +/- 14.80 mu m). In univariate regression analysis, age had no statistical significant effect on RNFL thickness (P = 0.7249) and refraction had a significant effect on RNFL thickness (P = 0.0008). Conclusion: OCT can be used to measure RNFL thickness in children. Refraction had an effect on RNFL thickness. In normal children, variation in RNFL thickness is large. The normative data provided by this study may assist in identifying changes in RNFL thickness in Indian children.