Repeatability of retinal thickness measurements in children using spectral domain optical coherence tomography

Abstract

AbstractPurpose: To evaluate the influence of age in the repeatability of retinal thickness measurements in a healthy paediatric population with spectral domain Optical Coherence Tomography (SD‐OCT). Knowledge of RNFL parameters and macular characteristics in a normal population and differences between ages and sexes is useful for evaluating normal development of the eyes. Also, an essential quality in determining the utility of a device for clinical use is its measurement variability. Repeatability is important for distinguishing normal subjects from patients with disease as well as for following ocular modifications over time for follow‐up after treatment, especially in young population.Methods: Seventy‐six eyes from 76 healthy paediatric subjects underwent three fast macula scans and 81 eyes from 81 healthy paediatric subjects were studied by three retinal nerve fiver layer (RNFL) measurements using a Spectralis OCT device. Mean thicknesses in the nine Early Treatment Diabetic Retinopathy Study (ETDRS) and in the seven optic nerve RNFL areas were measured. Mean values were evaluated by age and by sex. Children were divided in two groups, Group 1/ 6 years old or younger and group 2/ children older than 6 years. We calculated the repeatability comparing the two age groups, looking for intraclass correlation coefficient (ICC) and coefficient of variation (COV) values.Results: In the younger group central macular thickness value was 262.52 ± 18.28, and the central RNFL 104.03 ± 7.99. In the group of children older than 6, central macular thickness was 270.57 ± 18.49 and the central RNFL 100.27 ± 8.58. No statistically significant differences were found. Central retina thickness COVs were 7.00 in group 1% and 6.83% in Group 2. Optic disc RNFL thickness COVs were 7.72% in Group 1 and 8.69% in Group 2. All ICCs were higher than 0.8 showing excellent correlation among the three measurements performed by the same operator.Conclusions: Repeatability of Spectralis OCTs is high in healthy macula measurements, and significantly higher with Spectralis. Small differences were found between repeatability of macular thickness measurements obtained by both devices analysed by age.