To define and measure macular thickness and volume using Fourier domain OCT (FD OCT) and compare the values with Stratus OCT in normal eyes and eyes with macular disease.

On the same day, macular thicknesses of the ETDRS 9 subfield and total macular volumes were measured in 35 eyes of 23 normal subjects and 19 diseased eyes of 24 patients with FD OCT and Stratus OCT. The macular cube scan protocol for FD OCT and the fast macular thickness map protocol for Stratus OCT were used to measure macular thicknesses.

Foveal thickness of the central subfield in FD OCT (251.49±79.45 µm) was thicker than the value of Stratus OCT (210.26±60.57 µm) ( p <0.001) in all eyes. Total macular volume was 7.72±1.06 mm³ and 7.04±0.96 mm³ for FD OCT and Stratus OCT, respectively (p<0.001). Retina thickness of the ETDRS 9 subfields in FD OCT was thicker than the value obtained using Stratus OCT. In addition, foveal thickness differences were statistically significant in both the normal and diseased eye groups.

Macular thickness and total macular volume as measured by the FD OCT were larger than the values obtained using the Stratus OCT in both the normal and the diseased eye groups. The measuring algorithm of FD OCT defines the top of RPE as the outer retinal boundary, but Stratus OCT defines the outer retinal boundary as the IS/OS junction of the photoreceptor. Therefore, macular thicknesses of FD OCT are thicker than those of Stratus OCT. This difference should be considered when comparing the results of FD OCT with those of Stratus OCT.