Zeiss CIRRUS HD-OCT 500, User Manual

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Appendix
2660021169012 Rev. A 2017-12 CIRRUS HD-OCT User Manual
A-22
were small. Based on R
2
values, age explains only 12% of the variability in some
parameters, while signal strength explains no more than 4%. Refractive error and axial
length explain less than 2% of variability. For these reasons, only age was used when
applying normative limits to Ganglion Cell Analysis parameters.
Age
The Ganglion Cell Analysis was developed utilizing 282 subjects aged 19 to 84. All
parameters decrease slowly with age.
Figure A-13 shows the average Ganglion Cell
Analysis within the measurement annulus as a function of age.
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Ethnicity
The ethnicity breakdown of the Ganglion Cell Analysis is as follows:
43% Caucasians, 24% Asians, 18% African American, 12% Hispanic, 1% Indian, and 2%
mixed ethnicity. There are statistically significant differences among them in GCL + IPL
thickness as shown in the table below for Average GCL + IPL Thickness.
Table A-4 Ethnicity Breakdown of the Ganglion Cell Analysis
Results revealed that the mean difference in the average thickness between any two race
groups is within 4.3 mm. Subjects of European Descent have thinner ganglion cell plus
inner plexiform layer thickness on average, while subjects of Hispanic and Chinese descent
have thicker ganglion cell plus inner plexiform layer thickness (p < 0.001).
European Descent Hispanic Descent African Descent Asian Descent
Average GCL + IPL Thickness ( μ m) 84.1 (7.8) 88.8 (6.4) 86.3 (7.8) 89.4 (7.2)