title: Reproducibility of retinal nerve fiber layer measurements with manual and automated centration in healthy subjects using spectralis spectral-domain optical coherence tomography.
abstract: Objective. The aim of this study was to test the reproducibility of the Heidelberg Spectralis SD-OCT and to determine if provided software retest function for follow-up exam is superior to manual centration. Design. Prospective, cross-sectional study. Participants. 20 healthy subjects. Methods. All subjects underwent SD-OCT testing to determine retinal nerve fiber layer (RNFL) measurements sequentially on two different days and with two different centration techniques. Within-subject standard deviation, coefficient of variation, and intraclass correlation coefficient were used to assess reproducibility. Results. RNFL measurements showed high reproducibility, low within-subject standard deviation (1.3), low coefficient of variation (0.63%), and low intra-class correlation coefficient (0.98 (95% CI 0.97-0.99)) in the automated centration and manual centration groups for average RNFL Thickness. Quadrants showed slightly higher variability in the manual group compared to the automated group (within-subject standard deviation 2.5-5.3 versus 1.1-2.4, resp.). Conclusions. SD-OCT provides high-resolution RNFL measurements with high reproducibility and low variability. The re-test function allows for easier recentration for longitudinal examinations with similar results in average RNFL, but less variability in quadrant RNFL. SD-OCT high reproducibility and low variability is a promising fact and should be further evaluated in longitudinal studies of RNFL.
authors.affiliation: Department of Ophthalmology and MS Clinic, Department of Neurology, University of British Columbia, Vancouver, BC, Canada V5Z 3N9.
authors.forename: Alex P
authors.initials: AP
authors.lastname: Lange
authors.affiliation: MS Clinic, Department of Neurology, The University of British Columbia, Vancouer, BC, Canada V6T 2B5.
authors.forename: Reza
authors.initials: R
authors.lastname: Sadjadi
authors.affiliation: Departments of Clinical Neurosciences and Surgery, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada T2N 1N4.
authors.forename: Fiona
authors.initials: F
authors.lastname: Costello
authors.affiliation: Jules-Gonin Eye Hospital, University of Lausanne, 1015 Lausanne, Switzerland.
authors.forename: Ivo
authors.initials: I
authors.lastname: Guber
authors.affiliation: MS Clinic, Department of Neurology, The University of British Columbia, Vancouer, BC, Canada V6T 2B5.
authors.forename: Anthony L
authors.initials: AL
authors.lastname: Traboulsee