Zeiss CIRRUS HD-OCT 500, Руководство пользователя

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Appendix
2660021169012 Rev. A 2017-12 CIRRUS HD-OCT User Manual
B-12
Study 3: Repeatability and Reproducibility of Macular Retinal Pigment Epithelium
Elevation Measurements
The objective of this study was to determine the repeatability and reproducibility of the
CIRRUS HD-OCT measurements of macular retinal pigment epithelium (RPE) elevation. A
total of 50 eyes of 44 subjects were qualified for inclusion into the data analysis. There
were 26 qualified eyes for Phase 1 and 24 qualified eyes for Phase 2. Subjects in each
phase of the study underwent a series of CIRRUS HD-OCT scans:
Phase 1: Inter–Device Variability
Subjects assigned to Phase 1 of the study underwent the following series of CIRRUS
HD-OCT scans using the three CIRRUS units. A single operator, Operator A, performed all
scans during Phase 1 of the protocol. The following study measures were acquired:
• Three acceptable Macular Cube 200x200 scans on one eye from three CIRRUS
HD-OCT instruments for a total of 9 scans
• Three acceptable Macular Cube 512x128 scans on the fellow eye from three CIRRUS
HD-OCT instruments for a total of 9 scans
Phase 2: Inter–Operator Variability
Subjects assigned to Phase 2 of the study underwent the following series of CIRRUS
HD-OCT scans using only CIRRUS Unit 1. Three operators acquired the scans on each
subject. the following study measures were acquired:
• Three acceptable Macular Cube 200x200 scans on one eye from one CIRRUS HD-OCT
instrument by three operators for a total of 9 scans
• Three acceptable Macular Cube 512x128 scans on the fellow eye from the same
CIRRUS HD-OCT instrument by three operators for a total of 9 scans
The repeatability and reproducibility SD and limits of the area of RPE elevations are seen in
Table B-12 below. The repeatability limit of area measurements within the 3 mm circle
was higher than that of the 5 mm circle in the 200x200 scans (0.3626 and 0.2834 mm
2
respectively). The reverse was true for the 512x128 scan (0.2343 and 0.4304 mm
2
respectively). The reproducibility limit of area measurements within the 3 mm circle was
almost the same as that of the 5 mm circle in the 200x200 scans (0.4389 and 0.4073mm
2
respectively). For the 512x128 scan, the reproducibility limits for the 5 mm circle was
double that of the 3 mm circle (0.5422 vs. 0.2794 mm
2
). The repeatability and
reproducibility limits will affect the ability to determine when measurements have changed
due to a change in pathology as opposed to random variability.