Comparison of retinal nerve fiber layer thickness measurements by spectral-domain optical coherence tomography systems using a phantom eye model.

To quantify differences in nerve fiber layer thickness measurements by various spectral-domain optical coherence tomography (SD-OCT) systems, we developed a phantom eye model. We tested twelve SD-OCT systems of four manufacturers. All systems combined overestimated the 49 µm thick phantom RNFL thickness on average by 18 µm. Within brands, thickness measurements differed statistically significant for one Topcon, one RTVue and one Cirrus. Between brands, thickness determined with RTVue and Topcon differed statistically significant from Cirrus and Spectralis. The maximum difference between mean thicknesses is 3.6 µm within brands and 7.7 µm between brands.