Repeatability, reproducibility and interocular difference in the assessments of optic nerve OCT in children– a Swedish population-based study

Background: The aim was, first, to collect normative data of the optic nerve head and the peripapillary retinal nerve fibre layer (RNFL) thickness assessed with Cirrus SD-OCT, in healthy children in a population-based study; second, using these data, to examine repeatability, reproducibility and the interocular difference. Methods: One-hundred and ten eyes from 57 children aged 6–15 born at term, were examined. Best-corrected visual acuity and refraction were assessed. Both eyes were examined and the interocular difference was calculated. Repeatability was calculated by one examiner performing three assessments. Thereafter, a second examiner repeated the assessments to calculate reproducibility. Results: Mean RNFL thickness was 99.2 (SD 8.8) μm, mean disc area 1.89 (SD 0.37) mm2 and mean rim area 1.52 (SD 0.26) mm2. No significant correlations with age, gender or refraction were found. Repeatability and reproducibility were good overall. There was interocular symmetry between the eyes. Conclusions: Normal values for optic nerve head and RNFL thickness assessed with Cirrus SD-OCT were gathered to obtain a normal material in children. High repeatability and reproducibility indicated reliability of assessments performed by different examiners on different occasions. Overall, good correlation between right and left eyes was found