OCULUS Pentacam, Руководство по толкованию

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10 Screening for refractive surgery
10.1.2 Proposed screening parameters
It is essential to check the settings for the fitting zone of the BFS in the settings of the Pentacam®,
since this influences the borderline numbers
(Figure 57) .
„ „
If you are using the manual (fixed)
9 mm
zone for fitting the BFS, the proposed screening
parameters I use are:
In the anterior elevation map differences between the BFS and the corneal contour less than
+12 μm are considered normal, while differences b12 μm and +15 μm are suspicious,
and differences > 15 μm are typically indicative of keratoconus. Similar numbers about 5 μm
higher apply to posterior elevation maps
„ „
If you are using the manual (fixed)
8 mm
zone for fitting the BFS, the proposed screening
parameters I use are:
Anterior elevation differences less than 8 μm are considered in the normal range, while
differences > 8 μm are typically indicative of keratoconus or other ectatic disorders (in the
central zone). Posterior elevation differences < 11 μm are considered in the normal range,
while differences >16 μm are suspicious
Figure 57: BFS fitting zone