# 4.3.- Case 2. Corneal astigmatism magnitude 0.9D and ATR

Here we have the second example for the interpretation of the plot. The analysis corresponds to Right eyes with corneal incisions of 2.5 mm at temporal location. We filtered for corneal astigmatism <0.9 D and preoperative against-the-rule.

The questions to solve are:

**What type of astigmatism do we have induced?**With-the-rule because the square point is at the left side of the plot.**Is the SIA significant?**Yes, because red ellipse is not cutting the center of coordinates.**What is the mean SIA magnitude and orientation?**0.37@88º**Do we have to consider SIA in future calculations of the IOL?**We can do it. Although in the analysis of individual cases the results might be not improved because the center of the plot is inside of the blue ellipse, if we consider a sample of several cases the results might be improved