Correlation between peripapillary retinal nerve fiber layer thickness and optic nerve head parameters using spectral domain optical coherence tomography.

Objective: To evaluate correlation between peripapillary retinal nerve fiber layer thickness (RNFL) and optic nerve head (ONH) parameters in normal participants using Spectral domain optical coherence tomography (OCT).

Methods: Sixty-five eyes of 65 healthy participants aged 13-79 years underwent ONH analysis and peripapillary RNFL thickness measurements using spectral domain OCT. The RNFL measurements were correlated with the data obtained with ONH analysis.

Results: The average and quadrant RNFL thickness did not show correlation with optic disc area. A positive correlation was found between average RNFL thickness and rim area (r=0.425, P=0.000) and negative correlation between average RNFL thickness and cup area (r=-0.249, P<0.046).

Conclusions: In our study, peripapillary RNFL thickness as measured by OCT did not show correlation with optic disc size. Despite a shorter distance between optic disc and circular scan margin, larger discs did not show a thicker RNFL. Interindividual variability of disc area probably minimizes the effect of various ONH size on RNFL thickness measurement.