Case 3: Cylinder Overcorrection From Measurement Of Keratometric Astigmatism - OCULUS Pentacam Interpretation Manual

20 Total corneal astigmatism for toric IOL
After considering the SIA = 0.2 D 90° the choice was between a SN6AT4 to correct the KA (predicted
residual astigmatism = 0.17 D 138°) and a SN6AT6 to correct the TCA (predicted residual astigmatism
= 0.13 D 122°). The former should correct 1.55 D at the corneal plane, the latter 2.57 D. We
implanted a SN6AT6 oriented at 160°. One month after surgery, the patient had no residual refractive
astigmatism.
20.3 Case 3: Cylinder overcorrection from measurement of
keratometric astigmatism
A 71-year-old man underwent cataract surgery in OS. Axial length was 22.87 mm and a 23.50 D
toric Acrysof was calculated for emmetropia. Traditional KA measurement (Figure 174) showed a
value of 1.9 D 79.2°, which was significantly higher than the Pentacam® TCRP at 3 mm (Figure 175),
measuring 1.2 D 74°.
Figure 174: 1 Large Color Map showing a keratometric astigmatism of 1.9 D 79.2°
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