TY - JOUR
T1 - A comparison of structural measurements using 2 stratus optical coherence tomography instruments
AU - Sehi, Mitra
AU - Guaqueta, Delia C.
AU - Feuer, William J.
AU - Greenfield, David S.
PY - 2007/5
Y1 - 2007/5
N2 - PURPOSE: To compare measures of peripapillary retinal nerve fiber layer (RNFL) thickness, optic disc topography, and central foveal thickness generated using 2 different Stratus optical coherence tomography (OCT) instruments. METHODS: Ten normal subjects and 10 glaucoma subjects were included. One randomly selected eye per subject was scanned consecutively using a fast RNFL thickness protocol, fast macular thickness map, and fast optic disc protocol by 2 experienced operators on 2 instruments. The order of the machines and operators were randomized. The output power of each machine was measured using an optical power meter. For each OCT measurement 2 factor fixed effects analyses of variance were performed and a restricted maximum likelihood variance component analysis of the proportion of variance due to subject, operator, and machine was calculated. RESULTS: Significant differences (P≤0.003) between OCT instruments were observed in average, superior, and inferior RNFL thickness and central foveal thickness values among normal eyes; and average and superior RNFL thickness and cup/disc area ratio values among glaucomatous eyes. Overall, the intermachine variability (0.0% to 16.4%) was larger than the interoperator variability (0.0% to 2.4%) for all OCT measurements. In the glaucoma group the variability due to machine differences was 2.6 μm for the average RNFL thickness, 5.7 μm for the superior RNFL thickness, 0 μm for the inferior RNFL thickness, 0.03 μm for the cup/disc area ratio, 0.01 μm for the cup/disc vertical ratio, and 2.8 μm for the average foveal thickness. CONCLUSIONS: Measurements of RNFL thickness, optic disc topography, and central foveal thickness significantly differ between OCT instruments.
AB - PURPOSE: To compare measures of peripapillary retinal nerve fiber layer (RNFL) thickness, optic disc topography, and central foveal thickness generated using 2 different Stratus optical coherence tomography (OCT) instruments. METHODS: Ten normal subjects and 10 glaucoma subjects were included. One randomly selected eye per subject was scanned consecutively using a fast RNFL thickness protocol, fast macular thickness map, and fast optic disc protocol by 2 experienced operators on 2 instruments. The order of the machines and operators were randomized. The output power of each machine was measured using an optical power meter. For each OCT measurement 2 factor fixed effects analyses of variance were performed and a restricted maximum likelihood variance component analysis of the proportion of variance due to subject, operator, and machine was calculated. RESULTS: Significant differences (P≤0.003) between OCT instruments were observed in average, superior, and inferior RNFL thickness and central foveal thickness values among normal eyes; and average and superior RNFL thickness and cup/disc area ratio values among glaucomatous eyes. Overall, the intermachine variability (0.0% to 16.4%) was larger than the interoperator variability (0.0% to 2.4%) for all OCT measurements. In the glaucoma group the variability due to machine differences was 2.6 μm for the average RNFL thickness, 5.7 μm for the superior RNFL thickness, 0 μm for the inferior RNFL thickness, 0.03 μm for the cup/disc area ratio, 0.01 μm for the cup/disc vertical ratio, and 2.8 μm for the average foveal thickness. CONCLUSIONS: Measurements of RNFL thickness, optic disc topography, and central foveal thickness significantly differ between OCT instruments.
KW - Central foveal thickness
KW - Optic disc topography
KW - Optical coherence tomography
KW - Retinal nerve fiber layer thickness
KW - Variability
UR - http://www.scopus.com/inward/record.url?scp=34247191582&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=34247191582&partnerID=8YFLogxK
U2 - 10.1097/IJG.0b013e3180391a72
DO - 10.1097/IJG.0b013e3180391a72
M3 - Article
C2 - 17438421
AN - SCOPUS:34247191582
VL - 16
SP - 287
EP - 292
JO - Journal of Glaucoma
JF - Journal of Glaucoma
SN - 1057-0829
IS - 3
ER -