Purpose: To compare surgically induced astigmatism among 3 sizes of temporal corneal incisions in cataract surgery.
Patients and methods: A retrospective review was carried out of case records of 48 patients (64 eyes) who underwent cataract surgery. The length of the corneal incision was 1.6 mm in five eyes, 2.2 mm in 33 eyes, and 3.0 mm in 26 eyes. Astigmatism was measured by keratometry readings before and 1 week, 1 month, and 3 months after surgery. Surgically induced astigmatism was calculated by vector analyses using the Cravy method.
Results: One week postoperatively, the mean surgically induced astigmatism was 0.00 +/- 0.69 diopter(D) in the 1.6 mm group, -0.05 +/- 0.61 D in the 2.2 mm group and 0.44 +/- 0.57 D in the 3.0 mm group. Three months after surgery, the mean surgically induced astigmatism was -0.05 +/- 0.08 D in the 1.6 mm group, -0.04 +/- 0.47 D in the 2.2 mm group and 0.47 +/- 0.59 D in the 3.0 mm group. The surgically induced astigmatism was significantly less in the 2.2 mm group than in the 3.0 mm group.
Conclusion: The amount of induced astigmatism was significantly less in temporal corneal micro-incision cataract surgery than in small incision surgery.