Astigmatic effect from phaco incision placement

Many patients desire a refractive correction at the same time as cataract surgery. This makes sense because we can correct a large degree of spherical refractive error as well as astigmatism with proper planning. The phaco incision that we use during cataract surgery can have a significant effect on the astigmatism of the eye, and it needs to be accounted for in our calculations.Many ophthalmologists split astigmatism patients into two primary groups: eyes that have with-the-rule (WTR) astigmatism and eyes that have against-the-rule (ATR) astigmatism (Figure 1). While a smaller number of patients will have oblique astigmatism, which typically has steep and flat meridians at about the 45° and 135° positions, the vast majority are either WTR or ATR. Our usual temporal phaco incision will affect these types of eyes differently.