Comparison of Retinal Thicknesses Measured Using Swept-Source and Spectral-Domain Optical Coherence Tomography Devices

BACKGROUND AND OBJECTIVE: To compare retinal thicknesses measured using swept-source optical coherence tomography (SS-OCT) and spectraldomain (SD) OCT devices. PATIENTS AND METHODS: In a cohort study of 76 healthy eyes and 21 eyes with high myopia, mean retinal thicknesses in ETDRS subfields were compared between OCT scans obtained from the Topcon DRI OCT-1 (Topcon, Tokyo, Japan), Spectralis OCT (Heidelberg Engineering, Heidelberg, Germany), and Cirrus HD-OCT (Carl Zeiss Meditec, Dublin, CA). RESULTS: Central retinal thickness measurements differed significantly among the three OCT devices (Spectralis: 271 mu m; Cirrus: 254 mu m; DRI OCT-1: 238 mu m; P < .001), with mean differences ranging from 15.6 mu m to 37 mu m. Intraclass correlation coefficients were at least 0.94 for any pair of machines. Similar results were observed in all nine ETDRS subfields. In all sectors, retinal thickness measurements obtained using the 3-D and radial scans of the SS-OCT were similar (mean differences: 0.7 to 3.8 mu m). CONCLUSION: Retinal thickness measurements obtained from DRI OCT-1 and SD-OCT are different and should be accounted for when comparing results of OCT scans from different devices.