Long-term course of induced astigmatism after clear corneal incision cataract surgery

To determine whether a small clear corneal temporal incision produces less surgically induced astigmatism than a larger incision.

One hundred three consecutive cases of postoperative astigmatism after clear corneal incision cataract surgery were studied for a minimum of 1 year. Only self-sealing incisions from the temporal side were made as follows: 3.2 mm (Group A); 4.0 mm (Group B); 5.2 mm (Group C). We considered the amount and axes of the keratometric readings at different times as well as their course over time. Induced astigmatism was calculated using three methods. Axial changes were also analyzed.

Immediately after the surgery, there was a small, surgically induced, with-the-rule astigmatic shift in all groups, which in most cases decreased to near preoperative levels with time. One year postoperatively. mean induced astigmatism was 0.09 diopter (D) in Group A, 0.26 D in Group B, and 0.54 D in Group C. Most cases had minimal axial changes. In Group A, 86% had an axial change of fewer than 30 degrees; in Group B, 76%; and Group C, 73%.

The smallest incision group had the least surgically induced astigmatism and axial change. All incision groups remained stable and had satisfactory clinical results.