So the first thing that you can do to affect corneal astigmatism is just to
change your wound construction.
A transverse incision will flatten the central cornea.
And also steepen the cornea to perpendicular axis.
You have minimal overall spherial effect, but
you do have an effect of the astigmatism.
Now, in modern cataract surgery,
the incisions that we do, tend to induce minimal astigmatism.
But, you can alter the way that you make your incision to cause more changes to
the corneal curvature.
Making a larger incision will lead to more flattening.
Making your incision more central, also, can lead to more flattening.
And making a shorter tunnel.
So, a shorter incision into the eye itself, can lead to more flattening.
And you can make these alterations as needed, on a patient per patient basis.