Influence of the eye-tracking-based follow-up function in retinal nerve fiber layer thickness using fourier-domain optical coherence tomography

To evaluate the eye-tracking-based follow-up (EBF) function in the reproducibility of the peripapillary retinal nerve fiber layer (RNFL) thickness measurements obtained with Fourier-domain optical coherence tomography (Fd-OCT). Thirty healthy subjects were imaged on an Fd-OCT device at the same visit by two examiners. Peripapillary circular scans in "high-speed" (HS) mode with the "automatic real time" (ART) set at 16 and in "high-resolution" (HR) mode with the ART off were obtained without and with the EBF function activated. Mean (± SD) global RNFL thickness was 105.1 (± 9.5) μm on HS mode and 105.4 (± 9.6) μm on HR mode. Interobserver analysis for global RNFL thickness revealed an intraclass correlation coefficient (ICC) greater than or equal to 0.96 for all but the HR mode without the use of EBF function (ICC = 0.73). Intraobserver analysis for global RNFL thickness revealed an ICC greater than 0.98 for all but the HR mode without the use of EBF function (ICC = 0.86). The interobserver and intraobserver analyses revealed the lowest ICC values for the temporal region on both HS and HR modes. Higher ICC values were obtained with the HS mode and when the EBF function was activated, particularly when using the HR mode. The EBF function had no influence in the reproducibility of the global peripapillary RNFL thickness measurements in healthy subjects on HS mode with ART on. However, reproducibility of the global RNFL thickness measurements on HR mode as well as of the temporal and temporal superior regions in both HS and HR modes was greater with the EBF function.