The limit of agreement (LoA) varied among the different layers and sectors analyzed and this trend was similar in all the groups. The mean difference in individual layer thickness between the scans was smaller than the instrument’s axial resolution in all 3 groups. The agreement between the thickness measurements with horizontal and vertical OCT scans was evaluated in 3 groups of eyes: healthy controls, eyes with history of optic neuritis and the fellow eyes. Two volumetric scans (B-scans oriented horizontally and vertically) were performed in 64 multiple sclerosis subjects with history of unilateral optic neuritis and 64 healthy controls. The similarities between horizontal and vertical Optical Coherence Tomography (OCT) scans for the individual retinal layer thickness measurements in the macula was evaluated.
