Retinal nerve fiber layer thickness in normal Hong Kong Chinese children measured with optical coherence tomography

PURPOSE: To obtain the retinal nerve fiber layer (RNFL) thickness normative values of Hong Kong children by using optical coherence tomography (OCT) and to investigate the effect of age and axial length (AL) on RNFL thickness. PATIENTS AND METHODS: One hundred and four normal children aged between 6 and 17 years were recruited for this study. The RNFL thickness was measured by OCT (Stratus OCT). AL was measured by the IOLMaster. RESULTS: The median age of our subjects was 9.75 years (range: 6.08 to 17.58 years). The mean full circle peripapillary RNFL (RNFL-FC) was 113.5 μm (SD 9.8) and 113.1 μm (SD 10.8) in the right and left eyes, respectively. Multiple linear regression analysis showed a significant negative correlation between AL and RNFL-FC in both the right (r=-0.23, P<0.05) and left eyes (r=-0.25, P<0.05). The effect was the strongest in the superior quadrant. Every 1 mm increase in AL would result in a decrease in RNFL-FC by 2.7 to 2.9 μm. Age did not show significant effect on RNFL-FC. CONCLUSIONS: This study provides normative RNFL values for Hong Kong Chinese children. It can be used as a reference for the screening of glaucoma in children. AL demonstrates a significant negative correlation with RNFL thickness.