True Net Power - OCULUS Pentacam Interpretation Manual

3 Differences between the various topography maps of Pentacam ®
3.4

True Net Power

This map (Figure 4) shows the optical power of the cornea based on two different refractive indices,
one for the anterior (corneal tissue: 1.376) and one for the posterior surface (aqueous humour:
1.336), as well as the sagittal curvature of each. These results are aggregated. The True Net Power
map thus takes effects "A" and "B" into account. The underlying equation is:
1,376 -1
1,336 -1,376
TrueNet Power = 1000 +
1000
*
*
r post_surface
r ant_surface
Figure 4: True Net Power map calculated by two spheric surfaces of
anterior r = 8 mm and posterior r = 6.58 mm
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