Retinal asymmetry in children measured with optical coherence tomography.

ABSTRACT

PURPOSE: To determinate the physiological asymmetry of retinal measurements in the pediatric population with Fourier-domain optical coherence tomography (Cirrus HD-OCT). DESIGN: Prospective cross-sectional study. METHODS: Three hundred and fifty-seven healthy children were recruited. All subjects underwent a comprehensive ophthalmologic examination and an evaluation of the retinal nerve fiber layer (RNFL), optic nerve head, and macula with Cirrus OCT. Differences between right and left eyes were calculated and values were compared by means of a paired t test. Normal ranges of interocular differences were established as the 2.5th and the 97.5th percentiles. The correlations between right and left eyes were assessed by the intraclass correlation coefficients. RESULTS: Mean best-corrected visual acuity (logMAR) was -0.01. Differences in the average RNFL between right and left eyes were not statistically significant. The RNFL in the right eyes was thicker in the temporal and nasal quadrants, whereas the left eyes showed thicker RNFL in the superior quadrant. The interocular difference tolerance limits for average RNFL and macular thicknesses were 13.00 µm and 23.20 µm, respectively. There was a strong correlation for all the parameters between the right and the left eyes. CONCLUSIONS: The asymmetry of retinal parameters might be more valuable than the absolute values in assessing certain early diseases. The interocular differences in average RNFL and macular thickness of normal individuals should not exceed 13 µm and 23 µm, respectively, if measured with Cirrus HD-OCT.