Zeiss CIRRUS HD-OCT 500, Руководство пользователя

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Appendix
2660021169012 Rev. A 2017-12 CIRRUS HD-OCT User Manual
A-30
Normal Values for Ganglion Cell Analyses
Post–hoc analysis was performed on the Macular Cube 200x200 and Macular Cube
512x128 cube scans, originally acquired for macular retinal thickness normative data, to
determine the typical distribution for Ganglion Cell Analysis parameters and the GCL + IPL
thickness map. This analysis compares the GCL + IPL thickness results to normal limits
derived from post–hoc analysis of scans used for the Asian macular normative database.
Data were analyzed using the CIRRUS 6.0 proprietary ganglion cell analysis segmentation
algorithm to obtain seven main summary parameters. The seven summary parameters were
Average GCL + IPL thickness and six sectoral thickness values of an elliptical annulus
centered on the macula. The schematic of the annulus can be seen in
Figure A-12 .
All Ganglion Cell Analysis parameters decrease slowly with age. Figure A-18 below shows
the average GCL + IPL thickness within the measurement annulus as a function of age.
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It should be noted that, although the age effect was statistically significant, the R
2
(coefficient of determination) of the simple regression model was small for each parameter.
This finding indicates that, although age affects GCL + IPL thickness significantly, it can
only explain a small percentage of the variation of the Ganglion Cell Analysis parameters.
The summary parameters for Asian study eyes displayed in Table A-5 show that the GCL
+ IPL thicknesses, which are measured in an annulus around the fovea, have a
homogeneous distribution. The mean thicknesses of the six zones in the annulus ranged
from 80.7 to 85.8
μ m. This finding is consistent with the expectation that in a healthy eye,
the retinal nerve fibers are uniformly distributed in a radial pattern around the fovea.