CHANGES IN VECTOR ASTIGMATISM AFTER SUPEROTEMPORAL VERSUS TEMPORAL CLEAR CORNEAL INCISION CATARACT SURGERY

Purpose: To investigate vector and refractive astigmatism changes after superotemporal versus temporal clear corneal incision cataract surgery.Methods: Patients were diagnosed with age-related cataract with corneal astigmatism < 1.5 diopters (D) and were divided into two groups: superotemporal incision (R group) and temporal incision (L group). Uncorrected visual acuity, manifest refraction, corneal topography, anterior segment optical coherence tomography was performed pre- and six months postoperatively. Total ocular astigmatism, corneal astigmatism, vector of surgically induced corneal astigmatism (SICA), non-corneal ocular residual astigmatism (N-CORA), postoperative intraocular lens decentration and tilt were analyzed.Results: Thirty-eight subjects were included: 21, R group; 17, L group. After surgery, the N-CORA decreased significantly from 1.17 +/- 0.72 D to 0.73 +/- 0.47 D in all patients (P=0.001), 1.03 +/- 0.52 D to 0.70 +/- 0.40 D in the R group (P=0.005) and 1.35 +/- 0.90 D to 0.78 +/- 0.55 D in the L group (P=0.033). Significant differences between the R and L groups were found in the postoperative meridian of anterior corneal astigmatism (75.95 +/- 52.50 vs 116.79 +/- 47.29; P=0.017), total corneal astigmatism (51.65 +/- 42.75 vs 95.20 +/- 57.32; P=0.011), J45 change vector of SICA in the anterior cornea (-0.10 +/- 0.18 vs 0.00 +/- 0.11; P=0.048) and total cornea surface (-0.14 +/- 0.17 vs 0.03 +/- 0.12; P=0.001).Conclusion: The N-CORA decreased significantly after cataract surgery. Superotemporal and temporal incisions caused differences in the meridian components of oblique astigmatism in some patients but did not have a significant effect on the magnitude of corneal astigmatism.