Abstract
Abstract: :
Purpose:Changes in the optic nerve head (ONH) and retinal nervefiber layers (RNFL) can be quantitatively monitored using animaging device called optical coherence tomography (OCT). Thelatest OCT–3 version 2 contains modifications to the softwaredesigned to improve reproducibility in RNFL measurements. Toevaluate these improvements, data from OCT–3 version 2were compared for reproducibility and variability to those ofOCT–3 version 1.Methods: The cross–sectional images of the RNFL from 16subjects (9 normal, 7 glaucoma) obtained from version 1 werereanalyzed using the new software and intra and inter observervariability calculated. The calculations were compared to thoseof the old software by using Shrout Fleiss coefficients to determineif a significant difference in reproducibility existed betweenthe two versions. Paired t–tests were utilized to establishwhich variables should be considered for use in following glaucomaResults: Overall, OCT–3 version 2 showed higher reproducibilitythan OCT–3 version 1 as indicated by Table 1. For allsubjects, RNFL thickness reproducibility was greater in allmeasured areas except the superior quadrant, where no significantdifference was found Table 1: Comparison of Shrout Fleiss coefficients between version1 and version 2
Table 2: Paired t–test results indicating the differencebetween version 1 and version 2 for all subjects Conclusions: Overall, version 2 of the OCT Stratus softwareanalysis has less variability than the previous version.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • nerve fiber layer • retina